Import bmake-20250618vendor/NetBSD/bmake/20250618

Intersting/relevant changes since bmake-20250414

ChangeLog since bmake-20250414

2025-06-18  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250618
	Merge with NetBSD make, pick up
	o parse.c: in a warning without location information,
	print the stack trace

2025-06-15  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250615
	Merge with NetBSD make, pick up
	o add on-demand inter-process stack traces
	o job.c,meta.c: do not discard empty lines in the output of a command
	o job.c: add job prefix if necessary in non-default filtered mode
	o parse.c,var.c: skip inter-process stack trace when
	MAKE_STACK_TRACE=no

2025-06-12  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250612
	Merge with NetBSD make, pick up
	o use a common style for unexpected error messages
	o parse.c: add program name to stack traces from sub-makes
	add quotes to "in directory" line in stack traces
	o var.c: check variable names for invalid characters when there
	are no modifiers to apply.  This detects and warns about gmake
	syntax like: $(addprefix -I, $(LIST))

2025-06-09  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250606
	Merge with NetBSD make, pick up
	o main.c: fix bug in handling of output of children in jobs mode

2025-05-28  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250528
	Merge with NetBSD make, pick up
	o show contents of MAKEFLAGS in the stack trace.
	o main.c: delay warning about bogus -J flag, if we end up in
	compat mode before the call to InitMaxJobs, the warning isn't
	necessary.

2025-05-25  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250525
	Merge with NetBSD make, pick up
	o main.c: set .CURDIR earlier so it can be reported in some errors.

2025-05-20  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250520
	Merge with NetBSD make, pick up
	o rename variables, remove now-redundant comments
	o job.c: clean up building the shell commands in parallel mode
	remove timeout for polling in parallel mode
	o main.c: clean up error message for malformed internal -J option

2025-05-11  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250511
	Merge with NetBSD make, pick up
	o job.c: rename token pool variables to be more descriptive
	move ContinueJobs further up, to eliminate a forward declaration
	error out if writing to an internal pipe fails
	clean up constant names and function names
	use uniform debug log messages for the token pool
	in the debug log, replace magic numbers with identifiers
	o main.c: clean up error message for malformed internal -J option
	o make.c: replace bitset in trace output with descriptive node
	attributes
	o targ.c: add end marker for -dg1, -dg2 and -dg3 debug log
	o var.c: fix order of error messages in the ":?" modifier

2025-04-25  Simon J Gerraty  <sjg@beast.crufty.net>

	* VERSION (_MAKE_VERSION): 20250424
	Merge with NetBSD make, pick up
	o cleanup; replace unsigned int with just unsigned
	Inline the TMPPAT macro, as it is only needed in a single place
	o move struct Job from job.h to job.c
	o job.c: group the code for handling the job token pool
	avoid excessive values of -j
	o make.c: fix grammar in debug log message

mk/ChangeLog since bmake-20250414

2025-05-28  Simon J Gerraty  <sjg@beast.crufty.net>

	* install-mk (MK_VERSION): 20250528

	* add dirdeps2dplibs.mk

2025-05-18  Simon J Gerraty  <sjg@beast.crufty.net>

	* install-mk (MK_VERSION): 20250518

	* meta.autodep.mk (META_FILES): re-work to fix filtering.
	if OPTIMIZE_OBJECT_META_FILES==yes
	provide a default META_FILE_OBJ_FILTER that selects a valid
	.SUFFIX to match *o.meta, there's no guarantee that it will be as
	simple as .o or .So etc.
	We have to defer evaluation until the target script is run
	for any of these filters to have any effect.
	Use :S,${.OBJDIR}/,, rather than :T incase there are objects
	in sub-dirs.

	* lib.mk: leverage ${.SUFFIXES} when setting dependencies.

	* add UPDATE_DEPENDFILE as a dependent option - follows
	DIRDEPS_BUILD and use MK_UPDATE_DEPENDFILE as default for
	UPDATE_DEPENDFILE when we think it should be yes.
	This allows override with -DWITH[OUT]_UPDATE_DEPENDFILE
	without overriding UPDATE_DEPENDFILE directly - which can lead to
	trouble.

2025-05-16  Simon J Gerraty  <sjg@beast.crufty.net>

	* install-mk (MK_VERSION): 20250515

	* meta2deps.py: resolve the target of a Move or Link first
	and track the last path resolved, then if the src is a relative
	path we can easily use that last path to resolve the src correctly.

	* meta2deps.sh: for a Move or Link add the dir of target path to
	the list used to resolve the src path.

90 files changed, 1848 insertions, 1157 deletions

diff --git a/ChangeLog b/ChangeLog
index 1ec90b7bccc8..0a5eced2d439 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,88 @@
+2025-06-18  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250618
+	Merge with NetBSD make, pick up
+	o parse.c: in a warning without location information,
+	print the stack trace
+
+2025-06-15  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250615
+	Merge with NetBSD make, pick up
+	o add on-demand inter-process stack traces
+	o job.c,meta.c: do not discard empty lines in the output of a command
+	o job.c: add job prefix if necessary in non-default filtered mode
+	o parse.c,var.c: skip inter-process stack trace when
+	MAKE_STACK_TRACE=no
+
+2025-06-12  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250612
+	Merge with NetBSD make, pick up
+	o use a common style for unexpected error messages
+	o parse.c: add program name to stack traces from sub-makes
+	add quotes to "in directory" line in stack traces
+	o var.c: check variable names for invalid characters when there
+	are no modifiers to apply.  This detects and warns about gmake
+	syntax like: $(addprefix -I, $(LIST))
+
+2025-06-09  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250606
+	Merge with NetBSD make, pick up
+	o main.c: fix bug in handling of output of children in jobs mode
+
+2025-05-28  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250528
+	Merge with NetBSD make, pick up
+	o show contents of MAKEFLAGS in the stack trace.
+	o main.c: delay warning about bogus -J flag, if we end up in
+	compat mode before the call to InitMaxJobs, the warning isn't
+	necessary.
+
+2025-05-25  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250525
+	Merge with NetBSD make, pick up
+	o main.c: set .CURDIR earlier so it can be reported in some errors.
+
+2025-05-20  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250520
+	Merge with NetBSD make, pick up
+	o rename variables, remove now-redundant comments
+	o job.c: clean up building the shell commands in parallel mode
+	remove timeout for polling in parallel mode
+	o main.c: clean up error message for malformed internal -J option
+
+2025-05-11  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250511
+	Merge with NetBSD make, pick up
+	o job.c: rename token pool variables to be more descriptive
+	move ContinueJobs further up, to eliminate a forward declaration
+	error out if writing to an internal pipe fails
+	clean up constant names and function names
+	use uniform debug log messages for the token pool
+	in the debug log, replace magic numbers with identifiers
+	o main.c: clean up error message for malformed internal -J option
+	o make.c: replace bitset in trace output with descriptive node
+	attributes
+	o targ.c: add end marker for -dg1, -dg2 and -dg3 debug log
+	o var.c: fix order of error messages in the ":?" modifier
+
+2025-04-25  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* VERSION (_MAKE_VERSION): 20250424
+	Merge with NetBSD make, pick up
+	o cleanup; replace unsigned int with just unsigned
+	Inline the TMPPAT macro, as it is only needed in a single place
+	o move struct Job from job.h to job.c
+	o job.c: group the code for handling the job token pool
+	avoid excessive values of -j
+	o make.c: fix grammar in debug log message
+
 2025-04-14  Simon J Gerraty  <sjg@beast.crufty.net>
 
 	* VERSION (_MAKE_VERSION): 20250414
diff --git a/FILES b/FILES
index 553f3211f29c..8bed07d546a3 100644
--- a/FILES
+++ b/FILES
@@ -76,6 +76,7 @@ unit-tests/archive-suffix.exp
 unit-tests/archive-suffix.mk
 unit-tests/archive.exp
 unit-tests/archive.mk
+unit-tests/check-expect.lua
 unit-tests/cmd-errors-jobs.exp
 unit-tests/cmd-errors-jobs.mk
 unit-tests/cmd-errors-lint.exp
@@ -410,6 +411,8 @@ unit-tests/job-output-long-lines.exp
 unit-tests/job-output-long-lines.mk
 unit-tests/job-output-null.exp
 unit-tests/job-output-null.mk
+unit-tests/job-output.exp
+unit-tests/job-output.mk
 unit-tests/jobs-empty-commands-error.exp
 unit-tests/jobs-empty-commands-error.mk
 unit-tests/jobs-empty-commands.exp
@@ -859,6 +862,8 @@ unit-tests/varname-make_print_var_on_error-jobs.exp
 unit-tests/varname-make_print_var_on_error-jobs.mk
 unit-tests/varname-make_print_var_on_error.exp
 unit-tests/varname-make_print_var_on_error.mk
+unit-tests/varname-make_stack_trace.exp
+unit-tests/varname-make_stack_trace.mk
 unit-tests/varname-makefile.exp
 unit-tests/varname-makefile.mk
 unit-tests/varname-makeflags.exp
diff --git a/VERSION b/VERSION
index 4e4949c5fd3e..1467403891f1 100644
--- a/VERSION
+++ b/VERSION
@@ -1,2 +1,2 @@
 # keep this compatible with sh and make
-_MAKE_VERSION=20250414
+_MAKE_VERSION=20250618
diff --git a/bmake.1 b/bmake.1
index 9e9f2d03a450..92ed9e201ea5 100644
--- a/bmake.1
+++ b/bmake.1
@@ -1,4 +1,4 @@
-.\"	$NetBSD: make.1,v 1.384 2025/04/04 18:36:47 sjg Exp $
+.\"	$NetBSD: make.1,v 1.385 2025/06/13 03:51:18 rillig Exp $
 .\"
 .\" Copyright (c) 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -29,7 +29,7 @@
 .\"
 .\"	from: @(#)make.1	8.4 (Berkeley) 3/19/94
 .\"
-.Dd April  4, 2025
+.Dd June 12, 2025
 .Dt BMAKE 1
 .Os
 .Sh NAME
@@ -2688,6 +2688,7 @@ uses the following environment variables, if they exist:
 .Ev MAKEOBJDIR ,
 .Ev MAKEOBJDIRPREFIX ,
 .Ev MAKESYSPATH ,
+.Ev MAKE_STACK_TRACE ,
 .Ev PWD ,
 and
 .Ev TMPDIR .
@@ -2707,6 +2708,12 @@ very early and the
 target is used to reset
 .Sq Va .OBJDIR ,
 there may be unexpected side effects.
+.Pp
+If the
+.Ev MAKE_STACK_TRACE
+environment variable is set to
+.Dq yes ,
+any stack traces include the call chain of the parent processes.
 .Sh FILES
 .Bl -tag -width /usr/share/mk -compact
 .It .depend
diff --git a/bmake.cat1 b/bmake.cat1
index e1340e1c78e0..667c80898def 100644
--- a/bmake.cat1
+++ b/bmake.cat1
@@ -1728,7 +1728,7 @@ SSPPEECCIIAALL TTAARRGGEETTSS
 EENNVVIIRROONNMMEENNTT
      bbmmaakkee uses the following environment variables, if they exist: MACHINE,
      MACHINE_ARCH, MAKE, MAKEFLAGS, MAKEOBJDIR, MAKEOBJDIRPREFIX, MAKESYSPATH,
-     PWD, and TMPDIR.
+     MAKE_STACK_TRACE, PWD, and TMPDIR.
 
      MAKEOBJDIRPREFIX and MAKEOBJDIR should be set in the environment or on
      the command line to bbmmaakkee and not as makefile variables; see the
@@ -1736,6 +1736,9 @@ EENNVVIIRROONNMMEENNTT
      via makefile variables but unless done very early and the `..OOBBJJDDIIRR'
      target is used to reset `_._O_B_J_D_I_R', there may be unexpected side effects.
 
+     If the MAKE_STACK_TRACE environment variable is set to "yes", any stack
+     traces include the call chain of the parent processes.
+
 FFIILLEESS
      .depend        list of dependencies
      makefile       first default makefile if no makefile is specified on the
@@ -1828,4 +1831,4 @@ BBUUGGSS
      attempt to suppress a cascade of unnecessary errors, can result in a
      seemingly unexplained `*** Error code 6'
 
-FreeBSD 14.2-RELEASE-p1          April 4, 2025         FreeBSD 14.2-RELEASE-p1
+FreeBSD 14.2-RELEASE-p1          June 12, 2025         FreeBSD 14.2-RELEASE-p1
diff --git a/compat.c b/compat.c
index 0da929e35b82..7a51a99be4ba 100644
--- a/compat.c
+++ b/compat.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: compat.c,v 1.262 2025/01/19 10:57:10 rillig Exp $	*/
+/*	$NetBSD: compat.c,v 1.267 2025/06/13 03:51:18 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -90,13 +90,16 @@
 #include "make.h"
 #include "dir.h"
 #include "job.h"
+#ifdef USE_META
+# include "meta.h"
+#endif
 #include "metachar.h"
 #include "pathnames.h"
 
 /*	"@(#)compat.c	8.2 (Berkeley) 3/19/94"	*/
-MAKE_RCSID("$NetBSD: compat.c,v 1.262 2025/01/19 10:57:10 rillig Exp $");
+MAKE_RCSID("$NetBSD: compat.c,v 1.267 2025/06/13 03:51:18 rillig Exp $");
 
-static GNode *curTarg = NULL;
+static GNode *curTarg;
 static pid_t compatChild;
 static int compatSigno;
 
@@ -107,7 +110,7 @@ static int compatSigno;
 static void
 CompatDeleteTarget(GNode *gn)
 {
-	if (gn != NULL && !GNode_IsPrecious(gn) &&
+	if (!GNode_IsPrecious(gn) &&
 	    (gn->type & OP_PHONY) == 0) {
 		const char *file = GNode_VarTarget(gn);
 		if (!opts.noExecute && unlink_file(file) == 0)
@@ -127,11 +130,9 @@ CompatDeleteTarget(GNode *gn)
 static void
 CompatInterrupt(int signo)
 {
-	CompatDeleteTarget(curTarg);
-
-	if (curTarg != NULL && !GNode_IsPrecious(curTarg)) {
-		/* Run .INTERRUPT only if hit with interrupt signal. */
-		if (signo == SIGINT) {
+	if (curTarg != NULL) {
+		CompatDeleteTarget(curTarg);
+		if (signo == SIGINT && !GNode_IsPrecious(curTarg)) {
 			GNode *gn = Targ_FindNode(".INTERRUPT");
 			if (gn != NULL)
 				Compat_Make(gn, gn);
@@ -309,8 +310,6 @@ Compat_RunCommand(const char *cmdp, GNode *gn, StringListNode *ln)
 		cmd++;
 	}
 
-	while (ch_isspace(*cmd))
-		cmd++;
 	if (cmd[0] == '\0')
 		goto register_command;
 
@@ -337,7 +336,7 @@ Compat_RunCommand(const char *cmdp, GNode *gn, StringListNode *ln)
 
 		if (Cmd_Argv(cmd, cmd_len, shargv, 5,
 			cmd_file, sizeof(cmd_file),
-			(errCheck && shellErrFlag != NULL),
+			errCheck && shellErrFlag != NULL,
 			DEBUG(SHELL)) < 0)
 			Fatal("cannot run \"%s\"", cmd);
 		av = shargv;
@@ -356,6 +355,7 @@ Compat_RunCommand(const char *cmdp, GNode *gn, StringListNode *ln)
 #endif
 
 	Var_ReexportVars(gn);
+	Var_ExportStackTrace(gn->name, cmd);
 
 	compatChild = Compat_Spawn(av);
 	free(mav);
@@ -730,7 +730,7 @@ InitSignals(void)
 }
 
 void
-Compat_MakeAll(GNodeList *targs)
+Compat_MakeAll(GNodeList *targets)
 {
 	GNode *errorNode = NULL;
 
@@ -753,10 +753,10 @@ Compat_MakeAll(GNodeList *targs)
 	 * Expand .USE nodes right now, because they can modify the structure
 	 * of the tree.
 	 */
-	Make_ExpandUse(targs);
+	Make_ExpandUse(targets);
 
-	while (!Lst_IsEmpty(targs)) {
-		GNode *gn = Lst_Dequeue(targs);
+	while (!Lst_IsEmpty(targets)) {
+		GNode *gn = Lst_Dequeue(targets);
 		Compat_Make(gn, gn);
 
 		if (gn->made == UPTODATE) {
diff --git a/cond.c b/cond.c
index 31fe21c4c8b6..f83163cbb50e 100644
--- a/cond.c
+++ b/cond.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: cond.c,v 1.372 2025/04/10 21:41:35 rillig Exp $	*/
+/*	$NetBSD: cond.c,v 1.373 2025/04/22 19:28:50 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -91,7 +91,7 @@
 #include "dir.h"
 
 /*	"@(#)cond.c	8.2 (Berkeley) 1/2/94"	*/
-MAKE_RCSID("$NetBSD: cond.c,v 1.372 2025/04/10 21:41:35 rillig Exp $");
+MAKE_RCSID("$NetBSD: cond.c,v 1.373 2025/04/22 19:28:50 rillig Exp $");
 
 /*
  * Conditional expressions conform to this grammar:
@@ -166,7 +166,7 @@ typedef struct CondParser {
 
 static CondResult CondParser_Or(CondParser *, bool);
 
-unsigned int cond_depth = 0;	/* current .if nesting level */
+unsigned cond_depth = 0;	/* current .if nesting level */
 
 /* Names for ComparisonOp. */
 static const char opname[][3] = { "<", "<=", ">", ">=", "==", "!=" };
@@ -1028,7 +1028,7 @@ Cond_EvalLine(const char *line)
 	} IfState;
 
 	static enum IfState *cond_states = NULL;
-	static unsigned int cond_states_cap = 128;
+	static unsigned cond_states_cap = 128;
 
 	bool plain;
 	bool (*evalBare)(const char *);
@@ -1221,7 +1221,7 @@ found_variable:
 void
 Cond_EndFile(void)
 {
-	unsigned int open_conds = cond_depth - CurFile_CondMinDepth();
+	unsigned open_conds = cond_depth - CurFile_CondMinDepth();
 
 	if (open_conds != 0) {
 		Parse_Error(PARSE_FATAL, "%u open conditional%s",
diff --git a/dir.c b/dir.c
index 106b475bda2a..217fd04e162b 100644
--- a/dir.c
+++ b/dir.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: dir.c,v 1.296 2025/04/11 17:21:31 rillig Exp $	*/
+/*	$NetBSD: dir.c,v 1.297 2025/06/12 18:51:05 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -132,7 +132,7 @@
 #include "job.h"
 
 /*	"@(#)dir.c	8.2 (Berkeley) 1/2/94"	*/
-MAKE_RCSID("$NetBSD: dir.c,v 1.296 2025/04/11 17:21:31 rillig Exp $");
+MAKE_RCSID("$NetBSD: dir.c,v 1.297 2025/06/12 18:51:05 rillig Exp $");
 
 /*
  * A search path is a list of CachedDir structures. A CachedDir has in it the
@@ -492,7 +492,7 @@ Dir_InitDot(void)
 
 	dir = SearchPath_Add(NULL, ".");
 	if (dir == NULL) {
-		Error("Cannot open `.' (%s)", strerror(errno));
+		Error("Cannot open \".\": %s", strerror(errno));
 		exit(2);	/* Not 1 so -q can distinguish error */
 	}
 
diff --git a/for.c b/for.c
index 2aa1398b1c4c..438fb4e84de0 100644
--- a/for.c
+++ b/for.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: for.c,v 1.184 2025/04/11 18:08:17 rillig Exp $	*/
+/*	$NetBSD: for.c,v 1.185 2025/04/22 19:28:50 rillig Exp $	*/
 
 /*
  * Copyright (c) 1992, The Regents of the University of California.
@@ -58,14 +58,14 @@
 #include "make.h"
 
 /*	"@(#)for.c	8.1 (Berkeley) 6/6/93"	*/
-MAKE_RCSID("$NetBSD: for.c,v 1.184 2025/04/11 18:08:17 rillig Exp $");
+MAKE_RCSID("$NetBSD: for.c,v 1.185 2025/04/22 19:28:50 rillig Exp $");
 
 
 typedef struct ForLoop {
 	Vector /* of 'char *' */ vars; /* Iteration variables */
 	SubstringWords items;	/* Substitution items */
 	Buffer body;		/* Unexpanded body of the loop */
-	unsigned int nextItem;	/* Where to continue iterating */
+	unsigned nextItem;	/* Where to continue iterating */
 } ForLoop;
 
 
@@ -330,7 +330,7 @@ ExprLen(const char *s, const char *e)
  * by ApplyModifier_Defined.
  */
 static void
-AddEscaped(Buffer *cmds, Substring item, char endc)
+AddEscaped(Buffer *body, Substring item, char endc)
 {
 	const char *p;
 	char ch;
@@ -344,18 +344,18 @@ AddEscaped(Buffer *cmds, Substring item, char endc)
 				 * XXX: Should a '\' be added here?
 				 * See directive-for-escape.mk, ExprLen.
 				 */
-				Buf_AddBytes(cmds, p, 1 + len);
+				Buf_AddBytes(body, p, 1 + len);
 				p += 1 + len;
 				continue;
 			}
-			Buf_AddByte(cmds, '\\');
+			Buf_AddByte(body, '\\');
 		} else if (ch == ':' || ch == '\\' || ch == endc)
-			Buf_AddByte(cmds, '\\');
+			Buf_AddByte(body, '\\');
 		else if (ch == '\n') {
 			Parse_Error(PARSE_FATAL, "newline in .for value");
 			ch = ' ';	/* prevent newline injection */
 		}
-		Buf_AddByte(cmds, ch);
+		Buf_AddByte(body, ch);
 		p++;
 	}
 }
@@ -365,7 +365,7 @@ AddEscaped(Buffer *cmds, Substring item, char endc)
  * expression like ${i} or ${i:...} or $(i) or $(i:...) with ":Uvalue".
  */
 static void
-ForLoop_SubstVarLong(ForLoop *f, unsigned int firstItem, Buffer *body,
+ForLoop_SubstVarLong(ForLoop *f, unsigned firstItem, Buffer *body,
 		     const char **pp, char endc, const char **inout_mark)
 {
 	size_t i;
@@ -400,7 +400,7 @@ ForLoop_SubstVarLong(ForLoop *f, unsigned int firstItem, Buffer *body,
  * expressions like $i with their ${:U...} expansion.
  */
 static void
-ForLoop_SubstVarShort(ForLoop *f, unsigned int firstItem, Buffer *body,
+ForLoop_SubstVarShort(ForLoop *f, unsigned firstItem, Buffer *body,
 		      const char *p, const char **inout_mark)
 {
 	char ch = *p;
@@ -444,7 +444,7 @@ found:
  * See unit-tests/directive-for-escape.mk.
  */
 static void
-ForLoop_SubstBody(ForLoop *f, unsigned int firstItem, Buffer *body)
+ForLoop_SubstBody(ForLoop *f, unsigned firstItem, Buffer *body)
 {
 	const char *p, *end;
 	const char *mark;	/* where the last substitution left off */
@@ -479,8 +479,8 @@ For_NextIteration(ForLoop *f, Buffer *body)
 	if (f->nextItem == f->items.len)
 		return false;
 
-	f->nextItem += (unsigned int)f->vars.len;
-	ForLoop_SubstBody(f, f->nextItem - (unsigned int)f->vars.len, body);
+	f->nextItem += (unsigned)f->vars.len;
+	ForLoop_SubstBody(f, f->nextItem - (unsigned)f->vars.len, body);
 	if (DEBUG(FOR)) {
 		char *details = ForLoop_Details(f);
 		debug_printf("For: loop body with %s:\n%s",
@@ -494,7 +494,7 @@ For_NextIteration(ForLoop *f, Buffer *body)
 void
 For_Break(ForLoop *f)
 {
-	f->nextItem = (unsigned int)f->items.len;
+	f->nextItem = (unsigned)f->items.len;
 }
 
 /* Run the .for loop, imitating the actions of an include file. */
diff --git a/hash.c b/hash.c
index e84ef412bdef..663378626b89 100644
--- a/hash.c
+++ b/hash.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: hash.c,v 1.79 2024/07/07 09:37:00 rillig Exp $	*/
+/*	$NetBSD: hash.c,v 1.80 2025/04/22 19:28:50 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -74,7 +74,7 @@
 #include "make.h"
 
 /*	"@(#)hash.c	8.1 (Berkeley) 6/6/93"	*/
-MAKE_RCSID("$NetBSD: hash.c,v 1.79 2024/07/07 09:37:00 rillig Exp $");
+MAKE_RCSID("$NetBSD: hash.c,v 1.80 2025/04/22 19:28:50 rillig Exp $");
 
 /*
  * The ratio of # entries to # buckets at which we rebuild the table to
@@ -83,10 +83,10 @@ MAKE_RCSID("$NetBSD: hash.c,v 1.79 2024/07/07 09:37:00 rillig Exp $");
 #define rebuildLimit 3
 
 /* This hash function matches Gosling's Emacs and java.lang.String. */
-static unsigned int
+static unsigned
 Hash_String(const char *key, const char **out_keyEnd)
 {
-	unsigned int h;
+	unsigned h;
 	const char *p;
 
 	h = 0;
@@ -98,10 +98,10 @@ Hash_String(const char *key, const char **out_keyEnd)
 }
 
 /* This hash function matches Gosling's Emacs and java.lang.String. */
-unsigned int
+unsigned
 Hash_Substring(Substring key)
 {
-	unsigned int h;
+	unsigned h;
 	const char *p;
 
 	h = 0;
@@ -111,7 +111,7 @@ Hash_Substring(Substring key)
 }
 
 static HashEntry *
-HashTable_Find(HashTable *t, Substring key, unsigned int h)
+HashTable_Find(HashTable *t, Substring key, unsigned h)
 {
 	HashEntry *he;
 	size_t keyLen = Substring_Length(key);
@@ -135,7 +135,7 @@ HashTable_Find(HashTable *t, Substring key, unsigned int h)
 void
 HashTable_Init(HashTable *t)
 {
-	unsigned int n = 16, i;
+	unsigned n = 16, i;
 	HashEntry **buckets = bmake_malloc(sizeof *buckets * n);
 	for (i = 0; i < n; i++)
 		buckets[i] = NULL;
@@ -176,7 +176,7 @@ HashEntry *
 HashTable_FindEntry(HashTable *t, const char *key)
 {
 	const char *keyEnd;
-	unsigned int h = Hash_String(key, &keyEnd);
+	unsigned h = Hash_String(key, &keyEnd);
 	return HashTable_Find(t, Substring_Init(key, keyEnd), h);
 }
 
@@ -193,7 +193,7 @@ HashTable_FindValue(HashTable *t, const char *key)
  * or return NULL.
  */
 void *
-HashTable_FindValueBySubstringHash(HashTable *t, Substring key, unsigned int h)
+HashTable_FindValueBySubstringHash(HashTable *t, Substring key, unsigned h)
 {
 	HashEntry *he = HashTable_Find(t, key, h);
 	return he != NULL ? he->value : NULL;
@@ -220,10 +220,10 @@ HashTable_MaxChain(const HashTable *t)
 static void
 HashTable_Enlarge(HashTable *t)
 {
-	unsigned int oldSize = t->bucketsSize;
+	unsigned oldSize = t->bucketsSize;
 	HashEntry **oldBuckets = t->buckets;
-	unsigned int newSize = 2 * oldSize;
-	unsigned int newMask = newSize - 1;
+	unsigned newSize = 2 * oldSize;
+	unsigned newMask = newSize - 1;
 	HashEntry **newBuckets = bmake_malloc(sizeof *newBuckets * newSize);
 	size_t i;
 
@@ -257,7 +257,7 @@ HashEntry *
 HashTable_CreateEntry(HashTable *t, const char *key, bool *out_isNew)
 {
 	const char *keyEnd;
-	unsigned int h = Hash_String(key, &keyEnd);
+	unsigned h = Hash_String(key, &keyEnd);
 	HashEntry *he = HashTable_Find(t, Substring_Init(key, keyEnd), h);
 
 	if (he != NULL) {
@@ -313,7 +313,7 @@ HashIter_Next(HashIter *hi)
 	HashTable *t = hi->table;
 	HashEntry *he = hi->entry;
 	HashEntry **buckets = t->buckets;
-	unsigned int bucketsSize = t->bucketsSize;
+	unsigned bucketsSize = t->bucketsSize;
 
 	if (he != NULL)
 		he = he->next;	/* skip the most recently returned entry */
diff --git a/hash.h b/hash.h
index d6f9d03fb3ab..d9cf708dbd91 100644
--- a/hash.h
+++ b/hash.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: hash.h,v 1.51 2024/07/07 09:37:00 rillig Exp $	*/
+/*	$NetBSD: hash.h,v 1.52 2025/04/22 19:28:50 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -82,22 +82,22 @@ typedef struct HashEntry {
 	struct HashEntry *next;	/* Used to link together all the entries
 				 * associated with the same bucket. */
 	void *value;
-	unsigned int hash;	/* hash value of the key */
+	unsigned hash;		/* hash value of the key */
 	char key[1];		/* key string, variable length */
 } HashEntry;
 
 /* The hash table containing the entries. */
 typedef struct HashTable {
 	HashEntry **buckets;
-	unsigned int bucketsSize;
-	unsigned int numEntries;
-	unsigned int bucketsMask; /* Used to select the bucket for a hash. */
+	unsigned bucketsSize;
+	unsigned numEntries;
+	unsigned bucketsMask;	/* Used to select the bucket for a hash. */
 } HashTable;
 
 /* State of an iteration over all entries in a table. */
 typedef struct HashIter {
 	HashTable *table;	/* Table being searched. */
-	unsigned int nextBucket; /* Next bucket to check (after current). */
+	unsigned nextBucket;	/* Next bucket to check (after current). */
 	HashEntry *entry;	/* Next entry to check in current bucket. */
 } HashIter;
 
@@ -131,8 +131,8 @@ void HashTable_Init(HashTable *);
 void HashTable_Done(HashTable *);
 HashEntry *HashTable_FindEntry(HashTable *, const char *) MAKE_ATTR_USE;
 void *HashTable_FindValue(HashTable *, const char *) MAKE_ATTR_USE;
-unsigned int Hash_Substring(Substring) MAKE_ATTR_USE;
-void *HashTable_FindValueBySubstringHash(HashTable *, Substring, unsigned int)
+unsigned Hash_Substring(Substring) MAKE_ATTR_USE;
+void *HashTable_FindValueBySubstringHash(HashTable *, Substring, unsigned)
     MAKE_ATTR_USE;
 HashEntry *HashTable_CreateEntry(HashTable *, const char *, bool *);
 void HashTable_Set(HashTable *, const char *, void *);
diff --git a/job.c b/job.c
index 4eca3df66aa8..b0debd3c9705 100644
--- a/job.c
+++ b/job.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: job.c,v 1.492 2025/04/12 13:00:21 rillig Exp $	*/
+/*	$NetBSD: job.c,v 1.516 2025/06/13 06:13:19 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -73,45 +73,29 @@
  * Create child processes and collect their output.
  *
  * Interface:
- *	Job_Init	Called to initialize this module. In addition,
- *			the .BEGIN target is made, including all of its
- *			dependencies before this function returns.
- *			Hence, the makefiles must have been parsed
- *			before this function is called.
+ *	Job_Init	Initialize this module and make the .BEGIN target.
  *
  *	Job_End		Clean up any memory used.
  *
- *	Job_Make	Start the creation of the given target.
+ *	Job_Make	Start making the given target.
  *
  *	Job_CatchChildren
- *			Check for and handle the termination of any
- *			children. This must be called reasonably
- *			frequently to keep the whole make going at
- *			a decent clip, since job table entries aren't
- *			removed until their process is caught this way.
+ *			Handle the termination of any children.
  *
  *	Job_CatchOutput
- *			Print any output our children have produced.
- *			Should also be called fairly frequently to
- *			keep the user informed of what's going on.
- *			If no output is waiting, it will block for
- *			a time given by the SEL_* constants, below,
- *			or until output is ready.
+ *			Print any output the child processes have produced.
  *
  *	Job_ParseShell	Given a special dependency line with target '.SHELL',
  *			define the shell that is used for the creation
  *			commands in jobs mode.
  *
- *	Job_Finish	Make the .END target. Should only be called when the
+ *	Job_Finish	Make the .END target. Must only be called when the
  *			job table is empty.
  *
- *	Job_AbortAll	Abort all currently running jobs. Do not handle
- *			output or do anything for the jobs, just kill them.
- *			Should only be called in an emergency.
+ *	Job_AbortAll	Kill all currently running jobs, in an emergency.
  *
  *	Job_CheckCommands
- *			Verify that the commands for a target are
- *			ok. Provide them if necessary and possible.
+ *			Add fallback commands to a target, if necessary.
  *
  *	Job_Touch	Update a target without really updating it.
  *
@@ -123,7 +107,6 @@
 #endif
 #include <sys/types.h>
 #include <sys/stat.h>
-#include <sys/file.h>
 #include <sys/time.h>
 #include "wait.h"
 
@@ -147,11 +130,111 @@
 #include "make.h"
 #include "dir.h"
 #include "job.h"
+#ifdef USE_META
+# include "meta.h"
+#endif
 #include "pathnames.h"
 #include "trace.h"
 
 /*	"@(#)job.c	8.2 (Berkeley) 3/19/94"	*/
-MAKE_RCSID("$NetBSD: job.c,v 1.492 2025/04/12 13:00:21 rillig Exp $");
+MAKE_RCSID("$NetBSD: job.c,v 1.516 2025/06/13 06:13:19 rillig Exp $");
+
+
+#ifdef USE_SELECT
+/*
+ * Emulate poll() in terms of select().  This is not a complete
+ * emulation but it is sufficient for make's purposes.
+ */
+
+#define poll emul_poll
+#define pollfd emul_pollfd
+
+struct emul_pollfd {
+	int fd;
+	short events;
+	short revents;
+};
+
+#define POLLIN		0x0001
+#define POLLOUT		0x0004
+
+int emul_poll(struct pollfd *, int, int);
+#endif
+
+struct pollfd;
+
+
+enum JobStatus {
+	JOB_ST_FREE,		/* Job is available */
+	JOB_ST_SET_UP,		/* Job is allocated but otherwise invalid */
+	JOB_ST_RUNNING,		/* Job is running, pid valid */
+	JOB_ST_FINISHED		/* Job is done (i.e. after SIGCHLD) */
+};
+
+static const char JobStatus_Name[][9] = {
+	"free",
+	"set-up",
+	"running",
+	"finished",
+};
+
+/*
+ * A Job manages the shell commands that are run to create a single target.
+ * Each job is run in a separate subprocess by a shell.  Several jobs can run
+ * in parallel.
+ *
+ * The shell commands for the target are written to a temporary file,
+ * then the shell is run with the temporary file as stdin, and the output
+ * of that shell is captured via a pipe.
+ *
+ * When a job is finished, Make_Update updates all parents of the node
+ * that was just remade, marking them as ready to be made next if all
+ * other dependencies are finished as well.
+ */
+struct Job {
+	/* The process ID of the shell running the commands */
+	int pid;
+
+	/* The target the child is making */
+	GNode *node;
+
+	/*
+	 * If one of the shell commands is "...", all following commands are
+	 * delayed until the .END node is made.  This list node points to the
+	 * first of these commands, if any.
+	 */
+	StringListNode *tailCmds;
+
+	/* This is where the shell commands go. */
+	FILE *cmdFILE;
+
+	int exit_status;	/* from wait4() in signal handler */
+
+	enum JobStatus status;
+
+	bool suspended;
+
+	/* Ignore non-zero exits */
+	bool ignerr;
+	/* Output the command before or instead of running it. */
+	bool echo;
+	/* Target is a special one. */
+	bool special;
+
+	int inPipe;		/* Pipe for reading output from job */
+	int outPipe;		/* Pipe for writing control commands */
+	struct pollfd *inPollfd; /* pollfd associated with inPipe */
+
+#define JOB_BUFSIZE	1024
+	/* Buffer for storing the output of the job, line by line. */
+	char outBuf[JOB_BUFSIZE + 1];
+	size_t outBufLen;
+
+#ifdef USE_META
+	struct BuildMon bm;
+#endif
+};
+
 
 /*
  * A shell defines how the commands are run.  All commands for a target are
@@ -264,6 +347,8 @@ static enum {			/* Why is the make aborting? */
 } aborting = ABORT_NONE;
 #define JOB_TOKENS "+EI+"	/* Token to requeue for each abort state */
 
+static const char aborting_name[][6] = { "NONE", "ERROR", "INTR", "WAIT" };
+
 /* Tracks the number of tokens currently "out" to build jobs. */
 int jobTokensRunning = 0;
 
@@ -426,11 +511,12 @@ static void watchfd(Job *);
 static void clearfd(Job *);
 
 static char *targPrefix = NULL;	/* To identify a job change in the output. */
-static Job tokenWaitJob;	/* token wait pseudo-job */
+
+static Job tokenPoolJob;	/* token wait pseudo-job */
 
 static Job childExitJob;	/* child exit pseudo-job */
-#define CHILD_EXIT "."
-#define DO_JOB_RESUME "R"
+#define CEJ_CHILD_EXITED '.'
+#define CEJ_RESUME_JOBS 'R'
 
 enum {
 	npseudojobs = 2		/* number of pseudo-jobs */
@@ -441,7 +527,6 @@ static volatile sig_atomic_t caught_sigchld;
 
 static void CollectOutput(Job *, bool);
 static void JobInterrupt(bool, int) MAKE_ATTR_DEAD;
-static void JobRestartJobs(void);
 static void JobSigReset(void);
 
 static void
@@ -477,17 +562,38 @@ Job_FlagsToString(const Job *job, char *buf, size_t bufsize)
 	    job->special ? 'S' : '-');
 }
 
+#ifdef USE_META
+struct BuildMon *
+Job_BuildMon(Job *job)
+{
+	return &job->bm;
+}
+#endif
+
+GNode *
+Job_Node(Job *job)
+{
+	return job->node;
+}
+
+int
+Job_Pid(Job *job)
+{
+	return job->pid;
+}
+
 static void
 DumpJobs(const char *where)
 {
-	Job *job;
+	const Job *job;
 	char flags[4];
 
-	debug_printf("job table @ %s\n", where);
+	debug_printf("%s, job table:\n", where);
 	for (job = job_table; job < job_table_end; job++) {
 		Job_FlagsToString(job, flags, sizeof flags);
-		debug_printf("job %d, status %d, flags %s, pid %d\n",
-		    (int)(job - job_table), job->status, flags, job->pid);
+		debug_printf("job %d, status %s, flags %s, pid %d\n",
+		    (int)(job - job_table), JobStatus_Name[job->status],
+		    flags, job->pid);
 	}
 }
 
@@ -514,39 +620,44 @@ JobDeleteTarget(GNode *gn)
 		Error("*** %s removed", file);
 }
 
-/*
- * JobSigLock/JobSigUnlock
- *
- * Signal lock routines to get exclusive access. Currently used to
- * protect `jobs' and `stoppedJobs' list manipulations.
- */
+/* Lock the jobs table and the jobs therein. */
 static void
-JobSigLock(sigset_t *omaskp)
+JobsTable_Lock(sigset_t *omaskp)
 {
-	if (sigprocmask(SIG_BLOCK, &caught_signals, omaskp) != 0) {
-		Punt("JobSigLock: sigprocmask: %s", strerror(errno));
-		sigemptyset(omaskp);
-	}
+	if (sigprocmask(SIG_BLOCK, &caught_signals, omaskp) != 0)
+		Punt("JobsTable_Lock: %s", strerror(errno));
 }
 
+/* Unlock the jobs table and the jobs therein. */
 static void
-JobSigUnlock(sigset_t *omaskp)
+JobsTable_Unlock(sigset_t *omaskp)
 {
 	(void)sigprocmask(SIG_SETMASK, omaskp, NULL);
 }
 
 static void
+SetNonblocking(int fd)
+{
+	int flags = fcntl(fd, F_GETFL, 0);
+	if (flags == -1)
+		Punt("SetNonblocking.get: %s", strerror(errno));
+	flags |= O_NONBLOCK;
+	if (fcntl(fd, F_SETFL, flags) == -1)
+		Punt("SetNonblocking.set: %s", strerror(errno));
+}
+
+static void
 JobCreatePipe(Job *job, int minfd)
 {
-	int i, fd, flags;
+	int i;
 	int pipe_fds[2];
 
 	if (pipe(pipe_fds) == -1)
-		Punt("Cannot create pipe: %s", strerror(errno));
+		Punt("JobCreatePipe: %s", strerror(errno));
 
 	for (i = 0; i < 2; i++) {
 		/* Avoid using low-numbered fds */
-		fd = fcntl(pipe_fds[i], F_DUPFD, minfd);
+		int fd = fcntl(pipe_fds[i], F_DUPFD, minfd);
 		if (fd != -1) {
 			close(pipe_fds[i]);
 			pipe_fds[i] = fd;
@@ -557,9 +668,9 @@ JobCreatePipe(Job *job, int minfd)
 	job->outPipe = pipe_fds[1];
 
 	if (fcntl(job->inPipe, F_SETFD, FD_CLOEXEC) == -1)
-		Punt("Cannot set close-on-exec: %s", strerror(errno));
+		Punt("SetCloseOnExec: %s", strerror(errno));
 	if (fcntl(job->outPipe, F_SETFD, FD_CLOEXEC) == -1)
-		Punt("Cannot set close-on-exec: %s", strerror(errno));
+		Punt("SetCloseOnExec: %s", strerror(errno));
 
 	/*
 	 * We mark the input side of the pipe non-blocking; we poll(2) the
@@ -567,12 +678,7 @@ JobCreatePipe(Job *job, int minfd)
 	 * race for the token when a new one becomes available, so the read
 	 * from the pipe should not block.
 	 */
-	flags = fcntl(job->inPipe, F_GETFL, 0);
-	if (flags == -1)
-		Punt("Cannot get flags: %s", strerror(errno));
-	flags |= O_NONBLOCK;
-	if (fcntl(job->inPipe, F_SETFL, flags) == -1)
-		Punt("Cannot set flags: %s", strerror(errno));
+	SetNonblocking(job->inPipe);
 }
 
 /* Pass the signal to each running job. */
@@ -581,43 +687,36 @@ JobCondPassSig(int signo)
 {
 	Job *job;
 
-	DEBUG1(JOB, "JobCondPassSig(%d) called.\n", signo);
+	DEBUG1(JOB, "JobCondPassSig: signal %d\n", signo);
 
 	for (job = job_table; job < job_table_end; job++) {
 		if (job->status != JOB_ST_RUNNING)
 			continue;
-		DEBUG2(JOB, "JobCondPassSig passing signal %d to child %d.\n",
+		DEBUG2(JOB, "JobCondPassSig passing signal %d to pid %d\n",
 		    signo, job->pid);
 		KILLPG(job->pid, signo);
 	}
 }
 
-/*
- * SIGCHLD handler.
- *
- * Sends a token on the child exit pipe to wake us up from select()/poll().
- */
 static void
-JobChildSig(int signo MAKE_ATTR_UNUSED)
+WriteOrDie(int fd, char ch)
 {
-	caught_sigchld = 1;
-	while (write(childExitJob.outPipe, CHILD_EXIT, 1) == -1 &&
-	       errno == EAGAIN)
-		continue;
+	if (write(fd, &ch, 1) != 1)
+		execDie("write", "child");
 }
 
+static void
+HandleSIGCHLD(int signo MAKE_ATTR_UNUSED)
+{
+	caught_sigchld = 1;
+	/* Wake up from poll(). */
+	WriteOrDie(childExitJob.outPipe, CEJ_CHILD_EXITED);
+}
 
-/* Resume all stopped jobs. */
 static void
-JobContinueSig(int signo MAKE_ATTR_UNUSED)
+HandleSIGCONT(int signo MAKE_ATTR_UNUSED)
 {
-	/*
-	 * Defer sending SIGCONT to our stopped children until we return
-	 * from the signal handler.
-	 */
-	while (write(childExitJob.outPipe, DO_JOB_RESUME, 1) == -1 &&
-	       errno == EAGAIN)
-		continue;
+	WriteOrDie(childExitJob.outPipe, CEJ_RESUME_JOBS);
 }
 
 /*
@@ -669,7 +768,7 @@ JobPassSig_suspend(int signo)
 	act.sa_flags = 0;
 	(void)sigaction(signo, &act, NULL);
 
-	DEBUG1(JOB, "JobPassSig_suspend passing signal %d to self.\n", signo);
+	DEBUG1(JOB, "JobPassSig_suspend passing signal %d to self\n", signo);
 
 	(void)kill(getpid(), signo);
 
@@ -698,7 +797,7 @@ JobPassSig_suspend(int signo)
 }
 
 static Job *
-JobFindPid(int pid, JobStatus status, bool isJobs)
+JobFindPid(int pid, enum JobStatus status, bool isJobs)
 {
 	Job *job;
 
@@ -733,8 +832,6 @@ ParseCommandFlags(char **pp, CommandFlags *out_cmdFlags)
 		p++;
 	}
 
-	pp_skip_whitespace(&p);
-
 	*pp = p;
 }
 
@@ -876,17 +973,13 @@ JobWriteSpecials(Job *job, ShellWriter *wr, const char *escCmd, bool run,
  * given to make, stick a shell-specific echoOff command in the script.
  *
  * If the command starts with '-' and the shell has no error control (none
- * of the predefined shells has that), ignore errors for the entire job.
- *
- * XXX: Why ignore errors for the entire job?  This is even documented in the
- * manual page, but without any rationale since there is no known rationale.
+ * of the predefined shells has that), ignore errors for the rest of the job.
  *
- * XXX: The manual page says the '-' "affects the entire job", but that's not
- * accurate.  The '-' does not affect the commands before the '-'.
+ * XXX: Why ignore errors for the entire job?  This is documented in the
+ * manual page, but without giving a rationale.
  *
- * If the command is just "...", skip all further commands of this job.  These
- * commands are attached to the .END node instead and will be run by
- * Job_Finish after all other targets have been made.
+ * If the command is just "...", attach all further commands of this job to
+ * the .END node instead, see Job_Finish.
  */
 static void
 JobWriteCommand(Job *job, ShellWriter *wr, StringListNode *ln, const char *ucmd)
@@ -1037,7 +1130,7 @@ JobSaveCommands(Job *job)
 }
 
 
-/* Called to close both input and output pipes when a job is finished. */
+/* Close both input and output pipes when a job is finished. */
 static void
 JobClosePipes(Job *job)
 {
@@ -1103,14 +1196,15 @@ JobFinishDoneExitedError(Job *job, WAIT_T *inout_status)
 static void
 JobFinishDoneExited(Job *job, WAIT_T *inout_status)
 {
-	DEBUG2(JOB, "Process %d [%s] exited.\n", job->pid, job->node->name);
+	DEBUG2(JOB, "Target %s, pid %d exited\n",
+	    job->node->name, job->pid);
 
 	if (WEXITSTATUS(*inout_status) != 0)
 		JobFinishDoneExitedError(job, inout_status);
 	else if (DEBUG(JOB)) {
 		SwitchOutputTo(job->node);
-		(void)printf("*** [%s] Completed successfully\n",
-		    job->node->name);
+		(void)printf("Target %s, pid %d exited successfully\n",
+		    job->node->name, job->pid);
 	}
 }
 
@@ -1136,25 +1230,16 @@ JobFinishDone(Job *job, WAIT_T *inout_status)
 }
 
 /*
- * Do final processing for the given job including updating parent nodes and
- * starting new jobs as available/necessary.
- *
- * Deferred commands for the job are placed on the .END node.
- *
- * If there was a serious error (job_errors != 0; not an ignored one), no more
- * jobs will be started.
- *
- * Input:
- *	job		job to finish
- *	status		sub-why job went away
+ * Finish the job, add deferred commands to the .END node, mark the job as
+ * free, update parent nodes and start new jobs as available/necessary.
  */
 static void
 JobFinish (Job *job, WAIT_T status)
 {
 	bool done, return_job_token;
 
-	DEBUG3(JOB, "JobFinish: %d [%s], status %d\n",
-	    job->pid, job->node->name, status);
+	DEBUG3(JOB, "JobFinish: target %s, pid %d, status %#x\n",
+	    job->node->name, job->pid, status);
 
 	if ((WIFEXITED(status) &&
 	     ((WEXITSTATUS(status) != 0 && !job->ignerr))) ||
@@ -1164,7 +1249,7 @@ JobFinish (Job *job, WAIT_T status)
 		JobClosePipes(job);
 		if (job->cmdFILE != NULL && job->cmdFILE != stdout) {
 			if (fclose(job->cmdFILE) != 0)
-				Punt("Cannot write shell script for '%s': %s",
+				Punt("Cannot write shell script for \"%s\": %s",
 				    job->node->name, strerror(errno));
 			job->cmdFILE = NULL;
 		}
@@ -1207,11 +1292,6 @@ JobFinish (Job *job, WAIT_T status)
 
 	if (aborting != ABORT_ERROR && aborting != ABORT_INTERRUPT &&
 	    (WAIT_STATUS(status) == 0)) {
-		/*
-		 * As long as we aren't aborting and the job didn't return a
-		 * non-zero status that we shouldn't ignore, we call
-		 * Make_Update to update the parents.
-		 */
 		JobSaveCommands(job);
 		job->node->made = MADE;
 		if (!job->special)
@@ -1229,13 +1309,11 @@ JobFinish (Job *job, WAIT_T status)
 	}
 
 	if (return_job_token)
-		Job_TokenReturn();
+		TokenPool_Return();
 
 	if (aborting == ABORT_ERROR && jobTokensRunning == 0) {
-		if (shouldDieQuietly(NULL, -1)) {
-			Job_Wait();
+		if (shouldDieQuietly(NULL, -1))
 			exit(2);
-		}
 		Fatal("%d error%s", job_errors, job_errors == 1 ? "" : "s");
 	}
 }
@@ -1320,7 +1398,7 @@ Job_Touch(GNode *gn, bool echo)
  *	abortProc	Function to abort with message
  *
  * Results:
- *	true if the commands list is/was ok.
+ *	true if the commands are ok.
  */
 bool
 Job_CheckCommands(GNode *gn, void (*abortProc)(const char *, ...))
@@ -1406,9 +1484,9 @@ JobExec(Job *job, char **argv)
 		int i;
 
 		debug_printf("Running %s\n", job->node->name);
-		debug_printf("\tCommand: ");
+		debug_printf("\tCommand:");
 		for (i = 0; argv[i] != NULL; i++) {
-			debug_printf("%s ", argv[i]);
+			debug_printf(" %s", argv[i]);
 		}
 		debug_printf("\n");
 	}
@@ -1422,17 +1500,18 @@ JobExec(Job *job, char **argv)
 	if (job->echo)
 		SwitchOutputTo(job->node);
 
-	/* No interruptions until this job is on the `jobs' list */
-	JobSigLock(&mask);
+	/* No interruptions until this job is in the jobs table. */
+	JobsTable_Lock(&mask);
 
 	/* Pre-emptively mark job running, pid still zero though */
 	job->status = JOB_ST_RUNNING;
 
 	Var_ReexportVars(job->node);
+	Var_ExportStackTrace(job->node->name, NULL);
 
 	cpid = FORK_FUNCTION();
 	if (cpid == -1)
-		Punt("Cannot fork: %s", strerror(errno));
+		Punt("fork: %s", strerror(errno));
 
 	if (cpid == 0) {
 		/* Child */
@@ -1448,37 +1527,26 @@ JobExec(Job *job, char **argv)
 		 */
 		JobSigReset();
 
-		/* Now unblock signals */
 		sigemptyset(&tmask);
-		JobSigUnlock(&tmask);
+		JobsTable_Unlock(&tmask);
 
-		/*
-		 * Must duplicate the input stream down to the child's input
-		 * and reset it to the beginning (again). Since the stream
-		 * was marked close-on-exec, we must clear that bit in the
-		 * new input.
-		 */
 		if (dup2(fileno(job->cmdFILE), STDIN_FILENO) == -1)
 			execDie("dup2", "job->cmdFILE");
 		if (fcntl(STDIN_FILENO, F_SETFD, 0) == -1)
-			execDie("fcntl clear close-on-exec", "stdin");
+			execDie("clear close-on-exec", "stdin");
 		if (lseek(STDIN_FILENO, 0, SEEK_SET) == -1)
 			execDie("lseek to 0", "stdin");
 
 		if (job->node->type & (OP_MAKE | OP_SUBMAKE)) {
 			/* Pass job token pipe to submakes. */
-			if (fcntl(tokenWaitJob.inPipe, F_SETFD, 0) == -1)
+			if (fcntl(tokenPoolJob.inPipe, F_SETFD, 0) == -1)
 				execDie("clear close-on-exec",
-				    "tokenWaitJob.inPipe");
-			if (fcntl(tokenWaitJob.outPipe, F_SETFD, 0) == -1)
+				    "tokenPoolJob.inPipe");
+			if (fcntl(tokenPoolJob.outPipe, F_SETFD, 0) == -1)
 				execDie("clear close-on-exec",
-				    "tokenWaitJob.outPipe");
+				    "tokenPoolJob.outPipe");
 		}
 
-		/*
-		 * Set up the child's output to be routed through the pipe
-		 * we've created for it.
-		 */
 		if (dup2(job->outPipe, STDOUT_FILENO) == -1)
 			execDie("dup2", "job->outPipe");
 
@@ -1524,36 +1592,31 @@ JobExec(Job *job, char **argv)
 		meta_job_parent(job, cpid);
 #endif
 
-	/*
-	 * Set the current position in the buffer to the beginning
-	 * and mark another stream to watch in the outputs mask
-	 */
-	job->curPos = 0;
+	job->outBufLen = 0;
 
 	watchfd(job);
 
 	if (job->cmdFILE != NULL && job->cmdFILE != stdout) {
 		if (fclose(job->cmdFILE) != 0)
-			Punt("Cannot write shell script for '%s': %s",
+			Punt("Cannot write shell script for \"%s\": %s",
 			    job->node->name, strerror(errno));
 		job->cmdFILE = NULL;
 	}
 
-	/* Now that the job is actually running, add it to the table. */
 	if (DEBUG(JOB)) {
-		debug_printf("JobExec(%s): pid %d added to jobs table\n",
+		debug_printf(
+		    "JobExec: target %s, pid %d added to jobs table\n",
 		    job->node->name, job->pid);
 		DumpJobs("job started");
 	}
-	JobSigUnlock(&mask);
+	JobsTable_Unlock(&mask);
 }
 
-/* Create the argv needed to execute the shell for a given job. */
 static void
-JobMakeArgv(Job *job, char **argv)
+BuildArgv(Job *job, char **argv)
 {
 	int argc;
-	static char args[10];	/* For merged arguments */
+	static char args[10];
 
 	argv[0] = UNCONST(shellName);
 	argc = 1;
@@ -1571,11 +1634,10 @@ JobMakeArgv(Job *job, char **argv)
 		 * practically relevant.
 		 */
 		(void)snprintf(args, sizeof args, "-%s%s",
-		    (job->ignerr ? "" :
-			(shell->errFlag != NULL ? shell->errFlag : "")),
-		    (!job->echo ? "" :
-			(shell->echoFlag != NULL ? shell->echoFlag : "")));
-
+		    !job->ignerr && shell->errFlag != NULL
+			? shell->errFlag : "",
+		    job->echo && shell->echoFlag != NULL
+			? shell->echoFlag : "");
 		if (args[1] != '\0') {
 			argv[argc] = args;
 			argc++;
@@ -1596,21 +1658,16 @@ JobMakeArgv(Job *job, char **argv)
 static void
 JobWriteShellCommands(Job *job, GNode *gn, bool *out_run)
 {
-	/*
-	 * tfile is the name of a file into which all shell commands
-	 * are put. It is removed before the child shell is executed,
-	 * unless DEBUG(SCRIPT) is set.
-	 */
-	char tfile[MAXPATHLEN];
-	int tfd;		/* File descriptor to the temp file */
+	char fname[MAXPATHLEN];
+	int fd;
 
-	tfd = Job_TempFile(TMPPAT, tfile, sizeof tfile);
+	fd = Job_TempFile(NULL, fname, sizeof fname);
 
-	job->cmdFILE = fdopen(tfd, "w+");
+	job->cmdFILE = fdopen(fd, "w+");
 	if (job->cmdFILE == NULL)
-		Punt("Could not fdopen %s", tfile);
+		Punt("Could not fdopen %s", fname);
 
-	(void)fcntl(fileno(job->cmdFILE), F_SETFD, FD_CLOEXEC);
+	(void)fcntl(fd, F_SETFD, FD_CLOEXEC);
 
 #ifdef USE_META
 	if (useMeta) {
@@ -1626,8 +1683,8 @@ JobWriteShellCommands(Job *job, GNode *gn, bool *out_run)
 void
 Job_Make(GNode *gn)
 {
-	Job *job;		/* new job descriptor */
-	char *argv[10];		/* Argument vector to shell */
+	Job *job;
+	char *argv[10];
 	bool cmdsOK;		/* true if the nodes commands were all right */
 	bool run;
 
@@ -1659,31 +1716,16 @@ Job_Make(GNode *gn)
 		job->cmdFILE = stdout;
 		run = false;
 
-		/*
-		 * We're serious here, but if the commands were bogus, we're
-		 * also dead...
-		 */
 		if (!cmdsOK) {
-			PrintOnError(gn, "\n");	/* provide some clue */
+			PrintOnError(gn, "\n");
 			DieHorribly();
 		}
 	} else if (((gn->type & OP_MAKE) && !opts.noRecursiveExecute) ||
 	    (!opts.noExecute && !opts.touch)) {
-		/*
-		 * The above condition looks very similar to
-		 * GNode_ShouldExecute but is subtly different.  It prevents
-		 * that .MAKE targets are touched since these are usually
-		 * virtual targets.
-		 */
-
 		int parseErrorsBefore;
 
-		/*
-		 * We're serious here, but if the commands were bogus, we're
-		 * also dead...
-		 */
 		if (!cmdsOK) {
-			PrintOnError(gn, "\n");	/* provide some clue */
+			PrintOnError(gn, "\n");
 			DieHorribly();
 		}
 
@@ -1693,10 +1735,6 @@ Job_Make(GNode *gn)
 			run = false;
 		(void)fflush(job->cmdFILE);
 	} else if (!GNode_ShouldExecute(gn)) {
-		/*
-		 * Just write all the commands to stdout in one fell swoop.
-		 * This still sets up job->tailCmds correctly.
-		 */
 		SwitchOutputTo(gn);
 		job->cmdFILE = stdout;
 		if (cmdsOK)
@@ -1708,20 +1746,15 @@ Job_Make(GNode *gn)
 		run = false;
 	}
 
-	/* If we're not supposed to execute a shell, don't. */
 	if (!run) {
 		if (!job->special)
-			Job_TokenReturn();
-		/* Unlink and close the command file if we opened one */
+			TokenPool_Return();
+
 		if (job->cmdFILE != NULL && job->cmdFILE != stdout) {
 			(void)fclose(job->cmdFILE);
 			job->cmdFILE = NULL;
 		}
 
-		/*
-		 * We only want to work our way up the graph if we aren't
-		 * here because the commands for the job were no good.
-		 */
 		if (cmdsOK && aborting == ABORT_NONE) {
 			JobSaveCommands(job);
 			job->node->made = MADE;
@@ -1731,15 +1764,8 @@ Job_Make(GNode *gn)
 		return;
 	}
 
-	/*
-	 * Set up the control arguments to the shell. This is based on the
-	 * flags set earlier for this job.
-	 */
-	JobMakeArgv(job, argv);
-
-	/* Create the pipe by which we'll get the shell's output. */
+	BuildArgv(job, argv);
 	JobCreatePipe(job, 3);
-
 	JobExec(job, argv);
 }
 
@@ -1751,197 +1777,111 @@ Job_Make(GNode *gn)
  * Return the part of the output that the calling function needs to output by
  * itself.
  */
-static char *
-PrintFilteredOutput(char *p, const char *endp)	/* XXX: p should be const */
+static const char *
+PrintFilteredOutput(Job *job, size_t len)
 {
-	char *ep;		/* XXX: should be const */
+	const char *p = job->outBuf, *ep, *endp;
 
 	if (shell->noPrint == NULL || shell->noPrint[0] == '\0')
 		return p;
 
-	/*
-	 * XXX: What happens if shell->noPrint occurs on the boundary of
-	 * the buffer?  To work correctly in all cases, this should rather
-	 * be a proper stream filter instead of doing string matching on
-	 * selected chunks of the output.
-	 */
-	while ((ep = strstr(p, shell->noPrint)) != NULL) {
-		if (ep != p) {
-			*ep = '\0';	/* XXX: avoid writing to the buffer */
-			/*
-			 * The only way there wouldn't be a newline after
-			 * this line is if it were the last in the buffer.
-			 * however, since the noPrint output comes after it,
-			 * there must be a newline, so we don't print one.
-			 */
-			/* XXX: What about null bytes in the output? */
-			(void)fprintf(stdout, "%s", p);
+	endp = p + len;
+	while ((ep = strstr(p, shell->noPrint)) != NULL && ep < endp) {
+		if (ep > p) {
+			if (!opts.silent)
+				SwitchOutputTo(job->node);
+			(void)fwrite(p, 1, (size_t)(ep - p), stdout);
 			(void)fflush(stdout);
 		}
 		p = ep + shell->noPrintLen;
 		if (p == endp)
 			break;
 		p++;		/* skip over the (XXX: assumed) newline */
-		pp_skip_whitespace(&p);
+		cpp_skip_whitespace(&p);
 	}
 	return p;
 }
 
 /*
- * This function is called whenever there is something to read on the pipe.
- * We collect more output from the given job and store it in the job's
- * outBuf. If this makes up a line, we print it tagged by the job's
- * identifier, as necessary.
+ * Collect output from the job. Print any complete lines.
  *
  * In the output of the shell, the 'noPrint' lines are removed. If the
  * command is not alone on the line (the character after it is not \0 or
  * \n), we do print whatever follows it.
  *
- * Input:
- *	job		the job whose output needs printing
- *	finish		true if this is the last time we'll be called
- *			for this job
+ * If finish is true, collect all remaining output for the job.
  */
 static void
 CollectOutput(Job *job, bool finish)
 {
-	bool gotNL;		/* true if got a newline */
-	bool fbuf;		/* true if our buffer filled up */
+	const char *p;
 	size_t nr;		/* number of bytes read */
 	size_t i;		/* auxiliary index into outBuf */
 	size_t max;		/* limit for i (end of current data) */
-	ssize_t nRead;		/* (Temporary) number of bytes read */
 
-	/* Read as many bytes as will fit in the buffer. */
 again:
-	gotNL = false;
-	fbuf = false;
-
-	nRead = read(job->inPipe, &job->outBuf[job->curPos],
-	    JOB_BUFSIZE - job->curPos);
-	if (nRead < 0) {
+	nr = (size_t)read(job->inPipe, job->outBuf + job->outBufLen,
+	    JOB_BUFSIZE - job->outBufLen);
+	if (nr == (size_t)-1) {
 		if (errno == EAGAIN)
 			return;
 		if (DEBUG(JOB))
 			perror("CollectOutput(piperead)");
 		nr = 0;
-	} else
-		nr = (size_t)nRead;
+	}
 
 	if (nr == 0)
 		finish = false;	/* stop looping */
 
-	/*
-	 * If we hit the end-of-file (the job is dead), we must flush its
-	 * remaining output, so pretend we read a newline if there's any
-	 * output remaining in the buffer.
-	 */
-	if (nr == 0 && job->curPos != 0) {
-		job->outBuf[job->curPos] = '\n';
+	if (nr == 0 && job->outBufLen > 0) {
+		job->outBuf[job->outBufLen] = '\n';
 		nr = 1;
 	}
 
-	max = job->curPos + nr;
-	for (i = job->curPos; i < max; i++)
+	max = job->outBufLen + nr;
+	job->outBuf[max] = '\0';
+
+	for (i = job->outBufLen; i < max; i++)
 		if (job->outBuf[i] == '\0')
 			job->outBuf[i] = ' ';
 
-	/* Look for the last newline in the bytes we just got. */
-	for (i = job->curPos + nr - 1;
-	     i >= job->curPos && i != (size_t)-1; i--) {
-		if (job->outBuf[i] == '\n') {
-			gotNL = true;
+	for (i = max; i > job->outBufLen; i--)
+		if (job->outBuf[i - 1] == '\n')
 			break;
-		}
-	}
 
-	if (!gotNL) {
-		job->curPos += nr;
-		if (job->curPos == JOB_BUFSIZE) {
-			/*
-			 * If we've run out of buffer space, we have no choice
-			 * but to print the stuff. sigh.
-			 */
-			fbuf = true;
-			i = job->curPos;
-		}
+	if (i == job->outBufLen) {
+		job->outBufLen = max;
+		if (max < JOB_BUFSIZE)
+			goto unfinished_line;
+		i = max;
 	}
-	if (gotNL || fbuf) {
-		/*
-		 * Need to send the output to the screen. Null terminate it
-		 * first, overwriting the newline character if there was one.
-		 * So long as the line isn't one we should filter (according
-		 * to the shell description), we print the line, preceded
-		 * by a target banner if this target isn't the same as the
-		 * one for which we last printed something.
-		 * The rest of the data in the buffer are then shifted down
-		 * to the start of the buffer and curPos is set accordingly.
-		 */
-		job->outBuf[i] = '\0';
-		if (i >= job->curPos) {
-			char *p;
-
-			/*
-			 * FIXME: SwitchOutputTo should be here, according to
-			 * the comment above.  But since PrintOutput does not
-			 * do anything in the default shell, this bug has gone
-			 * unnoticed until now.
-			 */
-			p = PrintFilteredOutput(job->outBuf, &job->outBuf[i]);
 
-			/*
-			 * There's still more in the output buffer. This time,
-			 * though, we know there's no newline at the end, so
-			 * we add one of our own free will.
-			 */
-			if (*p != '\0') {
-				if (!opts.silent)
-					SwitchOutputTo(job->node);
+	p = PrintFilteredOutput(job, i);
+	if (*p != '\0') {
+		if (!opts.silent)
+			SwitchOutputTo(job->node);
 #ifdef USE_META
-				if (useMeta) {
-					meta_job_output(job, p,
-					    gotNL ? "\n" : "");
-				}
+		if (useMeta)
+			meta_job_output(job, p);
 #endif
-				(void)fprintf(stdout, "%s%s", p,
-				    gotNL ? "\n" : "");
-				(void)fflush(stdout);
-			}
-		}
-		/*
-		 * max is the last offset still in the buffer. Move any
-		 * remaining characters to the start of the buffer and
-		 * update the end marker curPos.
-		 */
-		if (i < max) {
-			(void)memmove(job->outBuf, &job->outBuf[i + 1],
-			    max - (i + 1));
-			job->curPos = max - (i + 1);
-		} else {
-			assert(i == max);
-			job->curPos = 0;
-		}
+		(void)fwrite(p, 1, (size_t)(job->outBuf + i - p), stdout);
+		(void)fflush(stdout);
 	}
-	if (finish) {
-		/*
-		 * If the finish flag is true, we must loop until we hit
-		 * end-of-file on the pipe. This is guaranteed to happen
-		 * eventually since the other end of the pipe is now closed
-		 * (we closed it explicitly and the child has exited). When
-		 * we do get an EOF, finish will be set false and we'll fall
-		 * through and out.
-		 */
+	memmove(job->outBuf, job->outBuf + i, max - i);
+	job->outBufLen = max - i;
+
+unfinished_line:
+	if (finish)
 		goto again;
-	}
 }
 
 static void
-JobRun(GNode *targ)
+JobRun(GNode *target)
 {
 	/* Don't let these special jobs overlap with other unrelated jobs. */
-	Compat_Make(targ, targ);
-	if (GNode_IsError(targ)) {
-		PrintOnError(targ, "\n\nStop.\n");
+	Compat_Make(target, target);
+	if (GNode_IsError(target)) {
+		PrintOnError(target, "\n\nStop.\n");
 		exit(1);
 	}
 }
@@ -1959,7 +1899,8 @@ Job_CatchChildren(void)
 	caught_sigchld = 0;
 
 	while ((pid = waitpid((pid_t)-1, &status, WNOHANG | WUNTRACED)) > 0) {
-		DEBUG2(JOB, "Process %d exited/stopped status %x.\n",
+		DEBUG2(JOB,
+		    "Process with pid %d exited/stopped with status %#x.\n",
 		    pid, WAIT_STATUS(status));
 		JobReapChild(pid, status, true);
 	}
@@ -1980,14 +1921,14 @@ JobReapChild(pid_t pid, WAIT_T status, bool isJobs)
 	job = JobFindPid(pid, JOB_ST_RUNNING, isJobs);
 	if (job == NULL) {
 		if (isJobs && !lurking_children)
-			Error("Child (%d) status %x not in table?",
+			Error("Child with pid %d and status %#x not in table?",
 			    pid, status);
 		return;
 	}
 
 	if (WIFSTOPPED(status)) {
-		DEBUG2(JOB, "Process %d (%s) stopped.\n",
-		    job->pid, job->node->name);
+		DEBUG2(JOB, "Process for target %s, pid %d stopped\n",
+		    job->node->name, job->pid);
 		if (!make_suspended) {
 			switch (WSTOPSIG(status)) {
 			case SIGTSTP:
@@ -2016,19 +1957,47 @@ JobReapChild(pid_t pid, WAIT_T status, bool isJobs)
 	JobFinish(job, status);
 }
 
+static void
+Job_Continue(Job *job)
+{
+	DEBUG1(JOB, "Continuing pid %d\n", job->pid);
+	if (job->suspended) {
+		(void)printf("*** [%s] Continued\n", job->node->name);
+		(void)fflush(stdout);
+		job->suspended = false;
+	}
+	if (KILLPG(job->pid, SIGCONT) != 0)
+		DEBUG1(JOB, "Failed to send SIGCONT to pid %d\n", job->pid);
+}
+
+static void
+ContinueJobs(void)
+{
+	Job *job;
+
+	for (job = job_table; job < job_table_end; job++) {
+		if (job->status == JOB_ST_RUNNING &&
+		    (make_suspended || job->suspended))
+			Job_Continue(job);
+		else if (job->status == JOB_ST_FINISHED)
+			JobFinish(job, job->exit_status);
+	}
+	make_suspended = false;
+}
+
 void
 Job_CatchOutput(void)
 {
 	int nready;
 	Job *job;
-	unsigned int i;
+	unsigned i;
 
 	(void)fflush(stdout);
 
 	do {
 		/* Maybe skip the job token pipe. */
 		nfds_t skip = wantToken ? 0 : 1;
-		nready = poll(fds + skip, fdsLen - skip, POLL_MSEC);
+		nready = poll(fds + skip, fdsLen - skip, -1);
 	} while (nready < 0 && errno == EINTR);
 
 	if (nready < 0)
@@ -2037,17 +2006,11 @@ Job_CatchOutput(void)
 	if (nready > 0 && childExitJob.inPollfd->revents & POLLIN) {
 		char token;
 		ssize_t count = read(childExitJob.inPipe, &token, 1);
-		if (count == 1) {
-			if (token == DO_JOB_RESUME[0])
-				/*
-				 * Complete relay requested from our SIGCONT
-				 * handler.
-				 */
-				JobRestartJobs();
-		} else if (count == 0)
-			Punt("unexpected eof on token pipe");
-		else if (errno != EAGAIN)
-			Punt("token pipe read: %s", strerror(errno));
+		if (count != 1)
+			Punt("childExitJob.read: %s",
+			    count == 0 ? "EOF" : strerror(errno));
+		if (token == CEJ_RESUME_JOBS)
+			ContinueJobs();
 		nready--;
 	}
 
@@ -2196,11 +2159,11 @@ Job_Init(void)
 	}
 
 	/* These are permanent entries and take slots 0 and 1 */
-	watchfd(&tokenWaitJob);
+	watchfd(&tokenPoolJob);
 	watchfd(&childExitJob);
 
 	sigemptyset(&caught_signals);
-	(void)bmake_signal(SIGCHLD, JobChildSig);
+	(void)bmake_signal(SIGCHLD, HandleSIGCHLD);
 	sigaddset(&caught_signals, SIGCHLD);
 
 	/* Handle the signals specified by POSIX. */
@@ -2218,7 +2181,7 @@ Job_Init(void)
 	AddSig(SIGTTOU, JobPassSig_suspend);
 	AddSig(SIGTTIN, JobPassSig_suspend);
 	AddSig(SIGWINCH, JobCondPassSig);
-	AddSig(SIGCONT, JobContinueSig);
+	AddSig(SIGCONT, HandleSIGCONT);
 
 	(void)Job_RunTarget(".BEGIN", NULL);
 	/* Create the .END node, see Targ_GetEndNode in Compat_MakeAll. */
@@ -2452,7 +2415,7 @@ JobInterrupt(bool runINTERRUPT, int signo)
 
 	aborting = ABORT_INTERRUPT;
 
-	JobSigLock(&mask);
+	JobsTable_Lock(&mask);
 
 	for (job = job_table; job < job_table_end; job++) {
 		if (job->status == JOB_ST_RUNNING && job->pid != 0) {
@@ -2471,7 +2434,7 @@ JobInterrupt(bool runINTERRUPT, int signo)
 		}
 	}
 
-	JobSigUnlock(&mask);
+	JobsTable_Unlock(&mask);
 
 	if (runINTERRUPT && !opts.touch) {
 		interrupt = Targ_FindNode(".INTERRUPT");
@@ -2512,9 +2475,8 @@ void
 Job_Wait(void)
 {
 	aborting = ABORT_WAIT;	/* Prevent other jobs from starting. */
-	while (jobTokensRunning != 0) {
+	while (jobTokensRunning != 0)
 		Job_CatchOutput();
-	}
 	aborting = ABORT_NONE;
 }
 
@@ -2544,42 +2506,6 @@ Job_AbortAll(void)
 		continue;
 }
 
-/*
- * Tries to restart stopped jobs if there are slots available.
- * Called in response to a SIGCONT.
- */
-static void
-JobRestartJobs(void)
-{
-	Job *job;
-
-	for (job = job_table; job < job_table_end; job++) {
-		if (job->status == JOB_ST_RUNNING &&
-		    (make_suspended || job->suspended)) {
-			DEBUG1(JOB, "Restarting stopped job pid %d.\n",
-			    job->pid);
-			if (job->suspended) {
-				(void)printf("*** [%s] Continued\n",
-				    job->node->name);
-				(void)fflush(stdout);
-			}
-			job->suspended = false;
-			if (KILLPG(job->pid, SIGCONT) != 0 && DEBUG(JOB)) {
-				debug_printf("Failed to send SIGCONT to %d\n",
-				    job->pid);
-			}
-		}
-		if (job->status == JOB_ST_FINISHED) {
-			/*
-			 * Job exit deferred after calling waitpid() in a
-			 * signal handler
-			 */
-			JobFinish(job, job->exit_status);
-		}
-	}
-	make_suspended = false;
-}
-
 static void
 watchfd(Job *job)
 {
@@ -2632,59 +2558,67 @@ clearfd(Job *job)
 	job->inPollfd = NULL;
 }
 
+int
+Job_TempFile(const char *pattern, char *tfile, size_t tfile_sz)
+{
+	int fd;
+	sigset_t mask;
+
+	JobsTable_Lock(&mask);
+	fd = mkTempFile(pattern, tfile, tfile_sz);
+	if (tfile != NULL && !DEBUG(SCRIPT))
+		unlink(tfile);
+	JobsTable_Unlock(&mask);
+
+	return fd;
+}
+
+static void
+TokenPool_Write(char tok)
+{
+	if (write(tokenPoolJob.outPipe, &tok, 1) != 1)
+		Punt("Cannot write \"%c\" to the token pool: %s",
+		    tok, strerror(errno));
+}
+
 /*
- * Put a token (back) into the job pipe.
+ * Put a token (back) into the job token pool.
  * This allows a make process to start a build job.
  */
 static void
-JobTokenAdd(void)
+TokenPool_Add(void)
 {
 	char tok = JOB_TOKENS[aborting], tok1;
 
 	/* If we are depositing an error token, flush everything else. */
-	while (tok != '+' && read(tokenWaitJob.inPipe, &tok1, 1) == 1)
+	while (tok != '+' && read(tokenPoolJob.inPipe, &tok1, 1) == 1)
 		continue;
 
-	DEBUG3(JOB, "(%d) aborting %d, deposit token %c\n",
-	    getpid(), aborting, tok);
-	while (write(tokenWaitJob.outPipe, &tok, 1) == -1 && errno == EAGAIN)
-		continue;
+	DEBUG3(JOB, "TokenPool_Add: pid %d, aborting %s, token %c\n",
+	    getpid(), aborting_name[aborting], tok);
+	TokenPool_Write(tok);
 }
 
-int
-Job_TempFile(const char *pattern, char *tfile, size_t tfile_sz)
+static void
+TokenPool_InitClient(int tokenPoolReader, int tokenPoolWriter)
 {
-	int fd;
-	sigset_t mask;
-
-	JobSigLock(&mask);
-	fd = mkTempFile(pattern, tfile, tfile_sz);
-	if (tfile != NULL && !DEBUG(SCRIPT))
-		unlink(tfile);
-	JobSigUnlock(&mask);
-
-	return fd;
+	tokenPoolJob.inPipe = tokenPoolReader;
+	tokenPoolJob.outPipe = tokenPoolWriter;
+	(void)fcntl(tokenPoolReader, F_SETFD, FD_CLOEXEC);
+	(void)fcntl(tokenPoolWriter, F_SETFD, FD_CLOEXEC);
 }
 
 /* Prepare the job token pipe in the root make process. */
-void
-Job_ServerStart(int max_tokens, int jp_0, int jp_1)
+static void
+TokenPool_InitServer(int maxJobTokens)
 {
 	int i;
 	char jobarg[64];
 
-	if (jp_0 >= 0 && jp_1 >= 0) {
-		tokenWaitJob.inPipe = jp_0;
-		tokenWaitJob.outPipe = jp_1;
-		(void)fcntl(jp_0, F_SETFD, FD_CLOEXEC);
-		(void)fcntl(jp_1, F_SETFD, FD_CLOEXEC);
-		return;
-	}
-
-	JobCreatePipe(&tokenWaitJob, 15);
+	JobCreatePipe(&tokenPoolJob, 15);
 
 	snprintf(jobarg, sizeof jobarg, "%d,%d",
-	    tokenWaitJob.inPipe, tokenWaitJob.outPipe);
+	    tokenPoolJob.inPipe, tokenPoolJob.outPipe);
 
 	Global_Append(MAKEFLAGS, "-J");
 	Global_Append(MAKEFLAGS, jobarg);
@@ -2692,68 +2626,74 @@ Job_ServerStart(int max_tokens, int jp_0, int jp_1)
 	/*
 	 * Preload the job pipe with one token per job, save the one
 	 * "extra" token for the primary job.
-	 *
-	 * XXX should clip maxJobs against PIPE_BUF -- if max_tokens is
-	 * larger than the write buffer size of the pipe, we will
-	 * deadlock here.
 	 */
-	for (i = 1; i < max_tokens; i++)
-		JobTokenAdd();
+	SetNonblocking(tokenPoolJob.outPipe);
+	for (i = 1; i < maxJobTokens; i++)
+		TokenPool_Add();
 }
 
-/* Return a withdrawn token to the pool. */
 void
-Job_TokenReturn(void)
+TokenPool_Init(int maxJobTokens, int tokenPoolReader, int tokenPoolWriter)
+{
+	if (tokenPoolReader >= 0 && tokenPoolWriter >= 0)
+		TokenPool_InitClient(tokenPoolReader, tokenPoolWriter);
+	else
+		TokenPool_InitServer(maxJobTokens);
+}
+
+/* Return a taken token to the pool. */
+void
+TokenPool_Return(void)
 {
 	jobTokensRunning--;
 	if (jobTokensRunning < 0)
 		Punt("token botch");
 	if (jobTokensRunning != 0 || JOB_TOKENS[aborting] != '+')
-		JobTokenAdd();
+		TokenPool_Add();
 }
 
 /*
- * Attempt to withdraw a token from the pool.
+ * Attempt to take a token from the pool.
  *
  * If the pool is empty, set wantToken so that we wake up when a token is
  * released.
  *
- * Returns true if a token was withdrawn, and false if the pool is currently
+ * Returns true if a token was taken, and false if the pool is currently
  * empty.
  */
 bool
-Job_TokenWithdraw(void)
+TokenPool_Take(void)
 {
 	char tok, tok1;
 	ssize_t count;
 
 	wantToken = false;
-	DEBUG3(JOB, "Job_TokenWithdraw(%d): aborting %d, running %d\n",
-	    getpid(), aborting, jobTokensRunning);
+	DEBUG3(JOB, "TokenPool_Take: pid %d, aborting %s, running %d\n",
+	    getpid(), aborting_name[aborting], jobTokensRunning);
 
-	if (aborting != ABORT_NONE || (jobTokensRunning >= opts.maxJobs))
+	if (aborting != ABORT_NONE || jobTokensRunning >= opts.maxJobs)
 		return false;
 
-	count = read(tokenWaitJob.inPipe, &tok, 1);
+	count = read(tokenPoolJob.inPipe, &tok, 1);
 	if (count == 0)
-		Fatal("eof on job pipe!");
+		Fatal("eof on job pipe");
 	if (count < 0 && jobTokensRunning != 0) {
 		if (errno != EAGAIN)
 			Fatal("job pipe read: %s", strerror(errno));
-		DEBUG1(JOB, "(%d) blocked for token\n", getpid());
+		DEBUG1(JOB, "TokenPool_Take: pid %d blocked for token\n",
+		    getpid());
 		wantToken = true;
 		return false;
 	}
 
 	if (count == 1 && tok != '+') {
 		/* make being aborted - remove any other job tokens */
-		DEBUG2(JOB, "(%d) aborted by token %c\n", getpid(), tok);
-		while (read(tokenWaitJob.inPipe, &tok1, 1) == 1)
+		DEBUG2(JOB, "TokenPool_Take: pid %d aborted by token %c\n",
+		    getpid(), tok);
+		while (read(tokenPoolJob.inPipe, &tok1, 1) == 1)
 			continue;
 		/* And put the stopper back */
-		while (write(tokenWaitJob.outPipe, &tok, 1) == -1 &&
-		       errno == EAGAIN)
-			continue;
+		TokenPool_Write(tok);
 		if (shouldDieQuietly(NULL, 1)) {
 			Job_Wait();
 			exit(6);
@@ -2764,12 +2704,10 @@ Job_TokenWithdraw(void)
 
 	if (count == 1 && jobTokensRunning == 0)
 		/* We didn't want the token really */
-		while (write(tokenWaitJob.outPipe, &tok, 1) == -1 &&
-		       errno == EAGAIN)
-			continue;
+		TokenPool_Write(tok);
 
 	jobTokensRunning++;
-	DEBUG1(JOB, "(%d) withdrew token\n", getpid());
+	DEBUG1(JOB, "TokenPool_Take: pid %d took a token\n", getpid());
 	return true;
 }
 
diff --git a/job.h b/job.h
index 4182dd6268d5..901be0eef1dd 100644
--- a/job.h
+++ b/job.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: job.h,v 1.81 2025/01/03 04:51:42 rillig Exp $	*/
+/*	$NetBSD: job.h,v 1.84 2025/04/22 19:28:50 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -78,106 +78,7 @@
 #ifndef MAKE_JOB_H
 #define MAKE_JOB_H
 
-#define TMPPAT	"makeXXXXXX"	/* relative to tmpdir */
-
-#ifdef USE_SELECT
-/*
- * Emulate poll() in terms of select().  This is not a complete
- * emulation but it is sufficient for make's purposes.
- */
-
-#define poll emul_poll
-#define pollfd emul_pollfd
-
-struct emul_pollfd {
-	int fd;
-	short events;
-	short revents;
-};
-
-#define POLLIN		0x0001
-#define POLLOUT		0x0004
-
-int emul_poll(struct pollfd *, int, int);
-#endif
-
-/*
- * The POLL_MSEC constant determines the maximum number of milliseconds spent
- * in poll before coming out to see if a child has finished.
- */
-#define POLL_MSEC	5000
-
-struct pollfd;
-
-
-#ifdef USE_META
-# include "meta.h"
-#endif
-
-typedef enum JobStatus {
-	JOB_ST_FREE	= 0,	/* Job is available */
-	JOB_ST_SET_UP	= 1,	/* Job is allocated but otherwise invalid */
-	/* XXX: What about the 2? */
-	JOB_ST_RUNNING	= 3,	/* Job is running, pid valid */
-	JOB_ST_FINISHED	= 4	/* Job is done (ie after SIGCHLD) */
-} JobStatus;
-
-/*
- * A Job manages the shell commands that are run to create a single target.
- * Each job is run in a separate subprocess by a shell.  Several jobs can run
- * in parallel.
- *
- * The shell commands for the target are written to a temporary file,
- * then the shell is run with the temporary file as stdin, and the output
- * of that shell is captured via a pipe.
- *
- * When a job is finished, Make_Update updates all parents of the node
- * that was just remade, marking them as ready to be made next if all
- * other dependencies are finished as well.
- */
-typedef struct Job {
-	/* The process ID of the shell running the commands */
-	int pid;
-
-	/* The target the child is making */
-	GNode *node;
-
-	/*
-	 * If one of the shell commands is "...", all following commands are
-	 * delayed until the .END node is made.  This list node points to the
-	 * first of these commands, if any.
-	 */
-	StringListNode *tailCmds;
-
-	/* This is where the shell commands go. */
-	FILE *cmdFILE;
-
-	int exit_status;	/* from wait4() in signal handler */
-
-	JobStatus status;
-
-	bool suspended;
-
-	/* Ignore non-zero exits */
-	bool ignerr;
-	/* Output the command before or instead of running it. */
-	bool echo;
-	/* Target is a special one. */
-	bool special;
-
-	int inPipe;		/* Pipe for reading output from job */
-	int outPipe;		/* Pipe for writing control commands */
-	struct pollfd *inPollfd; /* pollfd associated with inPipe */
-
-#define JOB_BUFSIZE	1024
-	/* Buffer for storing the output of the job, line by line. */
-	char outBuf[JOB_BUFSIZE + 1];
-	size_t curPos;		/* Current position in outBuf. */
-
-#ifdef USE_META
-	struct BuildMon bm;
-#endif
-} Job;
+typedef struct Job Job;
 
 extern char *shellPath;
 extern const char *shellName;
@@ -187,6 +88,11 @@ extern int jobTokensRunning;	/* tokens currently "out" */
 
 void Shell_Init(void);
 const char *Shell_GetNewline(void) MAKE_ATTR_USE;
+
+void TokenPool_Init(int, int, int);
+bool TokenPool_Take(void) MAKE_ATTR_USE;
+void TokenPool_Return(void);
+
 void Job_Touch(GNode *, bool);
 bool Job_CheckCommands(GNode *, void (*abortProc)(const char *, ...))
     MAKE_ATTR_USE;
@@ -201,12 +107,14 @@ void Job_End(void);
 #endif
 void Job_Wait(void);
 void Job_AbortAll(void);
-void Job_TokenReturn(void);
-bool Job_TokenWithdraw(void) MAKE_ATTR_USE;
-void Job_ServerStart(int, int, int);
 void Job_SetPrefix(void);
 bool Job_RunTarget(const char *, const char *);
 void Job_FlagsToString(const Job *, char *, size_t);
 int Job_TempFile(const char *, char *, size_t) MAKE_ATTR_USE;
+#ifdef USE_META
+struct BuildMon *Job_BuildMon(Job *) MAKE_ATTR_USE;
+#endif
+GNode *Job_Node(Job *) MAKE_ATTR_USE;
+int Job_Pid(Job *) MAKE_ATTR_USE;
 
 #endif
diff --git a/main.c b/main.c
index 3f0da61caf1d..d020ba85f16b 100644
--- a/main.c
+++ b/main.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: main.c,v 1.641 2025/03/31 14:35:22 riastradh Exp $	*/
+/*	$NetBSD: main.c,v 1.659 2025/06/13 05:41:36 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -104,11 +104,14 @@
 #include "make.h"
 #include "dir.h"
 #include "job.h"
+#ifdef USE_META
+# include "meta.h"
+#endif
 #include "pathnames.h"
 #include "trace.h"
 
 /*	"@(#)main.c	8.3 (Berkeley) 3/19/94"	*/
-MAKE_RCSID("$NetBSD: main.c,v 1.641 2025/03/31 14:35:22 riastradh Exp $");
+MAKE_RCSID("$NetBSD: main.c,v 1.659 2025/06/13 05:41:36 rillig Exp $");
 #if defined(MAKE_NATIVE)
 __COPYRIGHT("@(#) Copyright (c) 1988, 1989, 1990, 1993 "
 	    "The Regents of the University of California.  "
@@ -127,8 +130,9 @@ bool deleteOnError;		/* .DELETE_ON_ERROR: set */
 
 static int maxJobTokens;	/* -j argument */
 static bool enterFlagObj;	/* -w and objdir != srcdir */
+static bool bogusJflag;		/* -J invalid */
 
-static int jp_0 = -1, jp_1 = -1; /* ends of parent job pipe */
+static int tokenPoolReader = -1, tokenPoolWriter = -1;
 bool doing_depend;		/* Set while reading .depend */
 static bool jobsRunning;	/* true if the jobs might be running */
 static const char *tracefile;
@@ -361,7 +365,8 @@ MainParseArgChdir(const char *argvalue)
 		exit(2);	/* Not 1 so -q can distinguish error */
 	}
 	if (getcwd(curdir, MAXPATHLEN) == NULL) {
-		(void)fprintf(stderr, "%s: %s.\n", progname, strerror(errno));
+		(void)fprintf(stderr, "%s: getcwd: %s\n",
+		    progname, strerror(errno));
 		exit(2);
 	}
 	if (!IsRelativePath(argvalue) &&
@@ -377,17 +382,19 @@ static void
 MainParseArgJobsInternal(const char *argvalue)
 {
 	char end;
-	if (sscanf(argvalue, "%d,%d%c", &jp_0, &jp_1, &end) != 2) {
+	if (sscanf(argvalue, "%d,%d%c",
+	    &tokenPoolReader, &tokenPoolWriter, &end) != 2) {
 		(void)fprintf(stderr,
-		    "%s: internal error -- J option malformed (%s)\n",
-		    progname, argvalue);
-		usage();
+		    "%s: error: invalid internal option "
+		    "\"-J %s\" in \"%s\"\n",
+		    progname, argvalue, curdir);
+		exit(2);
 	}
-	if ((fcntl(jp_0, F_GETFD, 0) < 0) ||
-	    (fcntl(jp_1, F_GETFD, 0) < 0)) {
-		jp_0 = -1;
-		jp_1 = -1;
-		opts.compatMake = true;
+	if ((fcntl(tokenPoolReader, F_GETFD, 0) < 0) ||
+	    (fcntl(tokenPoolWriter, F_GETFD, 0) < 0)) {
+		tokenPoolReader = -1;
+		tokenPoolWriter = -1;
+		bogusJflag = true;
 	} else {
 		Global_Append(MAKEFLAGS, "-J");
 		Global_Append(MAKEFLAGS, argvalue);
@@ -708,7 +715,9 @@ Main_ParseArgLine(const char *line)
 		return;
 	}
 	free(buf);
+	EvalStack_PushMakeflags(line);
 	MainParseArgs((int)words.len, words.words);
+	EvalStack_Pop();
 
 	Words_Free(words);
 }
@@ -738,7 +747,7 @@ Main_SetObjdir(bool writable, const char *fmt, ...)
 		return false;
 
 	if ((writable && access(path, W_OK) != 0) || chdir(path) != 0) {
-		(void)fprintf(stderr, "%s: warning: %s: %s.\n",
+		(void)fprintf(stderr, "%s: warning: %s: %s\n",
 		    progname, path, strerror(errno));
 		/* Allow debugging how we got here - not always obvious */
 		if (GetBooleanExpr("${MAKE_DEBUG_OBJDIR_CHECK_WRITABLE}",
@@ -828,7 +837,7 @@ MakeMode(void)
 }
 
 static void
-PrintVar(const char *varname, bool expandVars)
+PrintVariable(const char *varname, bool expandVars)
 {
 	if (strchr(varname, '$') != NULL) {
 		char *evalue = Var_Subst(varname, SCOPE_GLOBAL, VARE_EVAL);
@@ -872,7 +881,7 @@ GetBooleanExpr(const char *expr, bool fallback)
 }
 
 static void
-doPrintVars(void)
+PrintVariables(void)
 {
 	StringListNode *ln;
 	bool expandVars;
@@ -885,49 +894,33 @@ doPrintVars(void)
 		expandVars = GetBooleanExpr("${.MAKE.EXPAND_VARIABLES}",
 		    false);
 
-	for (ln = opts.variables.first; ln != NULL; ln = ln->next) {
-		const char *varname = ln->datum;
-		PrintVar(varname, expandVars);
-	}
+	for (ln = opts.variables.first; ln != NULL; ln = ln->next)
+		PrintVariable(ln->datum, expandVars);
 }
 
 static bool
-runTargets(void)
+MakeTargets(void)
 {
-	GNodeList targs = LST_INIT;	/* target nodes to create */
+	GNodeList targets = LST_INIT;
 	bool outOfDate;		/* false if all targets up to date */
 
-	/*
-	 * Have now read the entire graph and need to make a list of
-	 * targets to create. If none was given on the command line,
-	 * we consult the parsing module to find the main target(s)
-	 * to create.
-	 */
 	if (Lst_IsEmpty(&opts.create))
-		Parse_MainName(&targs);
+		Parse_MainName(&targets);
 	else
-		Targ_FindList(&targs, &opts.create);
+		Targ_FindList(&targets, &opts.create);
 
 	if (!opts.compatMake) {
-		/*
-		 * Initialize job module before traversing the graph
-		 * now that any .BEGIN and .END targets have been read.
-		 * This is done only if the -q flag wasn't given
-		 * (to prevent the .BEGIN from being executed should
-		 * it exist).
-		 */
 		if (!opts.query) {
 			Job_Init();
 			jobsRunning = true;
 		}
 
-		/* Traverse the graph, checking on all the targets */
-		outOfDate = Make_Run(&targs);
+		outOfDate = Make_MakeParallel(&targets);
 	} else {
-		Compat_MakeAll(&targs);
+		Compat_MakeAll(&targets);
 		outOfDate = false;
 	}
-	Lst_Done(&targs);	/* Don't free the targets themselves. */
+	Lst_Done(&targets);	/* Don't free the targets themselves. */
 	return outOfDate;
 }
 
@@ -958,7 +951,7 @@ InitRandom(void)
 	struct timeval tv;
 
 	gettimeofday(&tv, NULL);
-	srandom((unsigned int)(tv.tv_sec + tv.tv_usec));
+	srandom((unsigned)(tv.tv_sec + tv.tv_usec));
 }
 
 static const char *
@@ -999,9 +992,9 @@ InitVarMachineArch(void)
 		const int mib[2] = { CTL_HW, HW_MACHINE_ARCH };
 		size_t len = sizeof machine_arch_buf;
 
-		if (sysctl(mib, (unsigned int)__arraycount(mib),
+		if (sysctl(mib, (unsigned)__arraycount(mib),
 		    machine_arch_buf, &len, NULL, 0) < 0) {
-			(void)fprintf(stderr, "%s: sysctl failed (%s).\n",
+			(void)fprintf(stderr, "%s: sysctl: %s\n",
 			    progname, strerror(errno));
 			exit(2);
 		}
@@ -1225,6 +1218,30 @@ InitMaxJobs(void)
 	char *value;
 	int n;
 
+	if (bogusJflag && !opts.compatMake) {
+		opts.compatMake = true;
+		Parse_Error(PARSE_WARNING,
+		    "internal option \"-J\" in \"%s\" "
+		    "refers to unopened file descriptors; "
+		    "falling back to compat mode.\n"
+		    "\t"
+		    "To run the target even in -n mode, "
+		    "add the .MAKE pseudo-source to the target.\n"
+		    "\t"
+		    "To run the target in default mode only, "
+		    "add a ${:D make} marker to a target's command. "
+		    "(This marker expression expands to an empty string.)\n"
+		    "\t"
+		    "To make the sub-make run in compat mode, add -B to "
+		    "its invocation.\n"
+		    "\t"
+		    "To make the sub-make independent from the parent make, "
+		    "unset the MAKEFLAGS environment variable in the "
+		    "target's commands.",
+		    curdir);
+		PrintStackTrace(true);
+		return;
+	}
 	if (forceJobs || opts.compatMake ||
 	    !Var_Exists(SCOPE_GLOBAL, ".MAKE.JOBS"))
 		return;
@@ -1345,7 +1362,7 @@ main_Init(int argc, char **argv)
 	UnlimitFiles();
 
 	if (uname(&utsname) == -1) {
-		(void)fprintf(stderr, "%s: uname failed (%s).\n", progname,
+		(void)fprintf(stderr, "%s: uname: %s\n", progname,
 		    strerror(errno));
 		exit(2);
 	}
@@ -1353,7 +1370,7 @@ main_Init(int argc, char **argv)
 	machine = InitVarMachine(&utsname);
 	machine_arch = InitVarMachineArch();
 
-	myPid = getpid();	/* remember this for vFork() */
+	myPid = getpid();
 
 	/* Just in case MAKEOBJDIR wants us to do something tricky. */
 	Targ_Init();
@@ -1439,25 +1456,25 @@ main_Init(int argc, char **argv)
 #endif
 	Dir_Init();
 
+	if (getcwd(curdir, MAXPATHLEN) == NULL) {
+		(void)fprintf(stderr, "%s: getcwd: %s\n",
+		    progname, strerror(errno));
+		exit(2);
+	}
+
 	{
 		char *makeflags = explode(getenv("MAKEFLAGS"));
 		Main_ParseArgLine(makeflags);
 		free(makeflags);
 	}
 
-	if (getcwd(curdir, MAXPATHLEN) == NULL) {
-		(void)fprintf(stderr, "%s: getcwd: %s.\n",
-		    progname, strerror(errno));
-		exit(2);
-	}
-
 	MainParseArgs(argc, argv);
 
 	if (opts.enterFlag)
 		printf("%s: Entering directory `%s'\n", progname, curdir);
 
 	if (stat(curdir, &sa) == -1) {
-		(void)fprintf(stderr, "%s: %s: %s.\n",
+		(void)fprintf(stderr, "%s: stat %s: %s\n",
 		    progname, curdir, strerror(errno));
 		exit(2);
 	}
@@ -1538,9 +1555,10 @@ main_PrepareMaking(void)
 		opts.compatMake = true;
 
 	if (!opts.compatMake)
-		Job_ServerStart(maxJobTokens, jp_0, jp_1);
+		TokenPool_Init(maxJobTokens, tokenPoolReader, tokenPoolWriter);
 	DEBUG5(JOB, "job_pipe %d %d, maxjobs %d, tokens %d, compat %d\n",
-	    jp_0, jp_1, opts.maxJobs, maxJobTokens, opts.compatMake ? 1 : 0);
+	    tokenPoolReader, tokenPoolWriter, opts.maxJobs, maxJobTokens,
+	    opts.compatMake ? 1 : 0);
 
 	if (opts.printVars == PVM_NONE)
 		Main_ExportMAKEFLAGS(true);	/* initial export */
@@ -1564,20 +1582,17 @@ main_PrepareMaking(void)
 }
 
 /*
- * Make the targets.
- * If the -v or -V options are given, print variables instead.
+ * Make the targets, or print variables.
  * Return whether any of the targets is out-of-date.
  */
 static bool
 main_Run(void)
 {
 	if (opts.printVars != PVM_NONE) {
-		/* print the values of any variables requested by the user */
-		doPrintVars();
+		PrintVariables();
 		return false;
-	} else {
-		return runTargets();
-	}
+	} else
+		return MakeTargets();
 }
 
 /* Clean up after making the targets. */
@@ -1620,9 +1635,8 @@ main_CleanUp(void)
 #endif
 }
 
-/* Determine the exit code. */
 static int
-main_Exit(bool outOfDate)
+main_ExitCode(bool outOfDate)
 {
 	if ((opts.strict && main_errors > 0) || parseErrors > 0)
 		return 2;	/* Not 1 so -q can distinguish error */
@@ -1639,7 +1653,7 @@ main(int argc, char **argv)
 	main_PrepareMaking();
 	outOfDate = main_Run();
 	main_CleanUp();
-	return main_Exit(outOfDate);
+	return main_ExitCode(outOfDate);
 }
 
 /*
@@ -1798,6 +1812,7 @@ Cmd_Exec(const char *cmd, char **error)
 	}
 
 	Var_ReexportVars(SCOPE_GLOBAL);
+	Var_ExportStackTrace(NULL, cmd);
 
 	switch (cpid = FORK_FUNCTION()) {
 	case 0:
@@ -2002,7 +2017,7 @@ execDie(const char *func, const char *arg)
 	char msg[1024];
 	int len;
 
-	len = snprintf(msg, sizeof(msg), "%s: %s(%s) failed (%s)\n",
+	len = snprintf(msg, sizeof(msg), "%s: %s(%s): %s\n",
 	    progname, func, arg, strerror(errno));
 	write_all(STDERR_FILENO, msg, (size_t)len);
 	_exit(1);
@@ -2218,7 +2233,7 @@ mkTempFile(const char *pattern, char *tfile, size_t tfile_sz)
 	int fd;
 
 	if (pattern == NULL)
-		pattern = TMPPAT;
+		pattern = "makeXXXXXX";
 	if (tmpdir == NULL)
 		tmpdir = getTmpdir();
 	if (tfile == NULL) {
@@ -2232,8 +2247,7 @@ mkTempFile(const char *pattern, char *tfile, size_t tfile_sz)
 		snprintf(tfile, tfile_sz, "%s%s", tmpdir, pattern);
 
 	if ((fd = mkstemp(tfile)) < 0)
-		Punt("Could not create temporary file %s: %s", tfile,
-		    strerror(errno));
+		Punt("mkstemp %s: %s", tfile, strerror(errno));
 	if (tfile == tbuf)
 		unlink(tfile);	/* we just want the descriptor */
 
diff --git a/make.1 b/make.1
index 579679a7af9a..37e890a24d21 100644
--- a/make.1
+++ b/make.1
@@ -1,4 +1,4 @@
-.\"	$NetBSD: make.1,v 1.384 2025/04/04 18:36:47 sjg Exp $
+.\"	$NetBSD: make.1,v 1.385 2025/06/13 03:51:18 rillig Exp $
 .\"
 .\" Copyright (c) 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -29,7 +29,7 @@
 .\"
 .\"	from: @(#)make.1	8.4 (Berkeley) 3/19/94
 .\"
-.Dd April  4, 2025
+.Dd June 12, 2025
 .Dt MAKE 1
 .Os
 .Sh NAME
@@ -2688,6 +2688,7 @@ uses the following environment variables, if they exist:
 .Ev MAKEOBJDIR ,
 .Ev MAKEOBJDIRPREFIX ,
 .Ev MAKESYSPATH ,
+.Ev MAKE_STACK_TRACE ,
 .Ev PWD ,
 and
 .Ev TMPDIR .
@@ -2707,6 +2708,12 @@ very early and the
 target is used to reset
 .Sq Va .OBJDIR ,
 there may be unexpected side effects.
+.Pp
+If the
+.Ev MAKE_STACK_TRACE
+environment variable is set to
+.Dq yes ,
+any stack traces include the call chain of the parent processes.
 .Sh FILES
 .Bl -tag -width /usr/share/mk -compact
 .It .depend
diff --git a/make.c b/make.c
index b784e812453b..3826c4d4e6a1 100644
--- a/make.c
+++ b/make.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: make.c,v 1.264 2024/06/02 15:31:26 rillig Exp $	*/
+/*	$NetBSD: make.c,v 1.272 2025/05/18 07:02:00 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -72,8 +72,8 @@
  * Examination of targets and their suitability for creation.
  *
  * Interface:
- *	Make_Run	Initialize things for the module. Returns true if
- *			work was (or would have been) done.
+ *	Make_MakeParallel
+ *			Make the targets in parallel mode.
  *
  *	Make_Update	After a target is made, update all its parents.
  *			Perform various bookkeeping chores like the updating
@@ -102,12 +102,15 @@
 #include "make.h"
 #include "dir.h"
 #include "job.h"
+#ifdef USE_META
+# include "meta.h"
+#endif
 
 /*	"@(#)make.c	8.1 (Berkeley) 6/6/93"	*/
-MAKE_RCSID("$NetBSD: make.c,v 1.264 2024/06/02 15:31:26 rillig Exp $");
+MAKE_RCSID("$NetBSD: make.c,v 1.272 2025/05/18 07:02:00 rillig Exp $");
 
 /* Sequence # to detect recursion. */
-static unsigned int checked_seqno = 1;
+static unsigned checked_seqno = 1;
 
 /*
  * The current fringe of the graph.
@@ -127,7 +130,7 @@ debug_printf(const char *fmt, ...)
 	va_end(ap);
 }
 
-static char *
+char *
 GNodeType_ToString(GNodeType type)
 {
 	Buffer buf;
@@ -250,7 +253,7 @@ IsOODateRegular(GNode *gn)
 /*
  * See if the node is out of date with respect to its sources.
  *
- * Used by Make_Run when deciding which nodes to place on the
+ * Used by Make_MakeParallel when deciding which nodes to place on the
  * toBeMade queue initially and by Make_Update to screen out .USE and
  * .EXEC nodes. In the latter case, however, any other sort of node
  * must be considered out-of-date since at least one of its children
@@ -392,9 +395,9 @@ PretendAllChildrenAreMade(GNode *pgn)
 }
 
 /*
- * Called by Make_Run and SuffApplyTransform on the downward pass to handle
- * .USE and transformation nodes, by copying the child node's commands, type
- * flags and children to the parent node.
+ * Called by Make_MakeParallel and SuffApplyTransform on the downward pass to
+ * handle .USE and transformation nodes, by copying the child node's commands,
+ * type flags and children to the parent node.
  *
  * A .USE node is much like an explicit transformation rule, except its
  * commands are always added to the target node, even if the target already
@@ -462,8 +465,8 @@ Make_HandleUse(GNode *cgn, GNode *pgn)
 }
 
 /*
- * Used by Make_Run on the downward pass to handle .USE nodes. Should be
- * called before the children are enqueued to be looked at by MakeAddChild.
+ * Used by Make_MakeParallel on the downward pass to handle .USE nodes. Should
+ * be called before the children are enqueued to be looked at by MakeAddChild.
  *
  * For a .USE child, the commands, type flags and children are copied to the
  * parent node, and since the relation to the .USE node is then no longer
@@ -487,13 +490,6 @@ MakeHandleUse(GNode *cgn, GNode *pgn, GNodeListNode *ln)
 	if (unmarked)
 		Make_HandleUse(cgn, pgn);
 
-	/*
-	 * This child node is now "made", so we decrement the count of
-	 * unmade children in the parent... We also remove the child
-	 * from the parent's list to accurately reflect the number of decent
-	 * children the parent has. This is used by Make_Run to decide
-	 * whether to queue the parent or examine its children...
-	 */
 	Lst_Remove(&pgn->children, ln);
 	pgn->unmade--;
 }
@@ -1024,7 +1020,7 @@ MakeStartJobs(void)
 		 * Get token now to avoid cycling job-list when we only
 		 * have 1 token
 		 */
-		if (!have_token && !Job_TokenWithdraw())
+		if (!have_token && !TokenPool_Take())
 			break;
 		have_token = true;
 
@@ -1045,25 +1041,18 @@ MakeStartJobs(void)
 			 * We've already looked at this node since a job
 			 * finished...
 			 */
-			DEBUG2(MAKE, "already checked %s%s\n", gn->name,
-			    gn->cohort_num);
+			DEBUG2(MAKE, "already checked %s%s\n",
+			    gn->name, gn->cohort_num);
 			gn->made = DEFERRED;
 			continue;
 		}
 		gn->checked_seqno = checked_seqno;
 
 		if (gn->unmade != 0) {
-			/*
-			 * We can't build this yet, add all unmade children
-			 * to toBeMade, just before the current first element.
-			 */
 			gn->made = DEFERRED;
-
 			MakeChildren(gn);
-
-			/* and drop this node on the floor */
-			DEBUG2(MAKE, "dropped %s%s\n", gn->name,
-			    gn->cohort_num);
+			DEBUG2(MAKE, "deferred %s%s\n",
+			    gn->name, gn->cohort_num);
 			continue;
 		}
 
@@ -1093,7 +1082,7 @@ MakeStartJobs(void)
 	}
 
 	if (have_token)
-		Job_TokenReturn();
+		TokenPool_Return();
 
 	return false;
 }
@@ -1105,12 +1094,12 @@ MakePrintStatusOrderNode(GNode *ogn, GNode *gn)
 	if (!GNode_IsWaitingFor(ogn))
 		return;
 
-	printf("    `%s%s' has .ORDER dependency against %s%s ",
+	printf("    `%s%s' has .ORDER dependency on %s%s ",
 	    gn->name, gn->cohort_num, ogn->name, ogn->cohort_num);
 	GNode_FprintDetails(stdout, "(", ogn, ")\n");
 
 	if (DEBUG(MAKE) && opts.debug_file != stdout) {
-		debug_printf("    `%s%s' has .ORDER dependency against %s%s ",
+		debug_printf("    `%s%s' has .ORDER dependency on %s%s ",
 		    gn->name, gn->cohort_num, ogn->name, ogn->cohort_num);
 		GNode_FprintDetails(opts.debug_file, "(", ogn, ")\n");
 	}
@@ -1236,17 +1225,12 @@ ExamineLater(GNodeList *examine, GNodeList *toBeExamined)
 	}
 }
 
-/*
- * Expand .USE nodes and create a new targets list.
- *
- * Input:
- *	targs		the initial list of targets
- */
+/* Expand .USE nodes and create a new targets list. */
 void
-Make_ExpandUse(GNodeList *targs)
+Make_ExpandUse(GNodeList *targets)
 {
 	GNodeList examine = LST_INIT;	/* Queue of targets to examine */
-	Lst_AppendAll(&examine, targs);
+	Lst_AppendAll(&examine, targets);
 
 	/*
 	 * Make an initial downward pass over the graph, marking nodes to
@@ -1256,15 +1240,15 @@ Make_ExpandUse(GNodeList *targs)
 	 * children for it if it has none and also has no commands. If the
 	 * node is a leaf, we stick it on the toBeMade queue to be looked
 	 * at in a minute, otherwise we add its children to our queue and
-	 * go on about our business.
+	 * go on.
 	 */
 	while (!Lst_IsEmpty(&examine)) {
 		GNode *gn = Lst_Dequeue(&examine);
 
 		if (gn->flags.remake)
-			/* We've looked at this one already */
 			continue;
 		gn->flags.remake = true;
+
 		DEBUG2(MAKE, "Make_ExpandUse: examine %s%s\n",
 		    gn->name, gn->cohort_num);
 
@@ -1318,31 +1302,26 @@ Make_ExpandUse(GNodeList *targs)
 
 /* Make the .WAIT node depend on the previous children */
 static void
-add_wait_dependency(GNodeListNode *owln, GNode *wn)
+AddWaitDependency(GNodeListNode *prevWaitNode, GNode *waitNode)
 {
-	GNodeListNode *cln;
-	GNode *cn;
-
-	for (cln = owln; (cn = cln->datum) != wn; cln = cln->next) {
-		DEBUG3(MAKE, ".WAIT: add dependency %s%s -> %s\n",
-		    cn->name, cn->cohort_num, wn->name);
+	GNodeListNode *ln;
 
-		/*
-		 * XXX: This pattern should be factored out, it repeats often
-		 */
-		Lst_Append(&wn->children, cn);
-		wn->unmade++;
-		Lst_Append(&cn->parents, wn);
+	for (ln = prevWaitNode; ln->datum != waitNode; ln = ln->next) {
+		GNode *gn = ln->datum;
+		DEBUG3(MAKE, ".WAIT: add dependency \"%s: %s%s\"\n",
+		    waitNode->name, gn->name, gn->cohort_num);
+		Lst_Append(&waitNode->children, gn);
+		Lst_Append(&gn->parents, waitNode);
+		waitNode->unmade++;
 	}
 }
 
 /* Convert .WAIT nodes into dependencies. */
 static void
-Make_ProcessWait(GNodeList *targs)
+Make_ProcessWait(GNodeList *targets)
 {
 	GNode *pgn;		/* 'parent' node we are examining */
-	GNodeListNode *owln;	/* Previous .WAIT node */
-	GNodeList examine;	/* List of targets to examine */
+	GNodeList examine;
 
 	/*
 	 * We need all the nodes to have a common parent in order for the
@@ -1358,7 +1337,7 @@ Make_ProcessWait(GNodeList *targs)
 
 	{
 		GNodeListNode *ln;
-		for (ln = targs->first; ln != NULL; ln = ln->next) {
+		for (ln = targets->first; ln != NULL; ln = ln->next) {
 			GNode *cgn = ln->datum;
 
 			Lst_Append(&pgn->children, cgn);
@@ -1374,7 +1353,7 @@ Make_ProcessWait(GNodeList *targs)
 	Lst_Append(&examine, pgn);
 
 	while (!Lst_IsEmpty(&examine)) {
-		GNodeListNode *ln;
+		GNodeListNode *waitNode, *ln;
 
 		pgn = Lst_Dequeue(&examine);
 
@@ -1387,85 +1366,39 @@ Make_ProcessWait(GNodeList *targs)
 		if (pgn->type & OP_DOUBLEDEP)
 			Lst_PrependAll(&examine, &pgn->cohorts);
 
-		owln = pgn->children.first;
+		waitNode = pgn->children.first;
 		for (ln = pgn->children.first; ln != NULL; ln = ln->next) {
 			GNode *cgn = ln->datum;
 			if (cgn->type & OP_WAIT) {
-				add_wait_dependency(owln, cgn);
-				owln = ln;
-			} else {
+				AddWaitDependency(waitNode, cgn);
+				waitNode = ln;
+			} else
 				Lst_Append(&examine, cgn);
-			}
 		}
 	}
 
 	Lst_Done(&examine);
 }
 
-/*
- * Initialize the nodes to remake and the list of nodes which are ready to
- * be made by doing a breadth-first traversal of the graph starting from the
- * nodes in the given list. Once this traversal is finished, all the 'leaves'
- * of the graph are in the toBeMade queue.
- *
- * Using this queue and the Job module, work back up the graph, calling on
- * MakeStartJobs to keep the job table as full as possible.
- *
- * Input:
- *	targs		the initial list of targets
- *
- * Results:
- *	True if work was done, false otherwise.
- *
- * Side Effects:
- *	The make field of all nodes involved in the creation of the given
- *	targets is set to 1. The toBeMade list is set to contain all the
- *	'leaves' of these subgraphs.
- */
 bool
-Make_Run(GNodeList *targs)
+Make_MakeParallel(GNodeList *targets)
 {
 	int errors;		/* Number of errors the Job module reports */
 
-	/* Start trying to make the current targets... */
 	Lst_Init(&toBeMade);
 
-	Make_ExpandUse(targs);
-	Make_ProcessWait(targs);
+	Make_ExpandUse(targets);
+	Make_ProcessWait(targets);
 
 	if (DEBUG(MAKE)) {
 		debug_printf("#***# full graph\n");
 		Targ_PrintGraph(1);
 	}
 
-	if (opts.query) {
-		/*
-		 * We wouldn't do any work unless we could start some jobs
-		 * in the next loop... (we won't actually start any, of
-		 * course, this is just to see if any of the targets was out
-		 * of date)
-		 */
+	if (opts.query)
 		return MakeStartJobs();
-	}
-	/*
-	 * Initialization. At the moment, no jobs are running and until some
-	 * get started, nothing will happen since the remaining upward
-	 * traversal of the graph is performed by the routines in job.c upon
-	 * the finishing of a job. So we fill the Job table as much as we can
-	 * before going into our loop.
-	 */
-	(void)MakeStartJobs();
 
-	/*
-	 * Main Loop: The idea here is that the ending of jobs will take
-	 * care of the maintenance of data structures and the waiting for
-	 * output will cause us to be idle most of the time while our
-	 * children run as much as possible. Because the job table is kept
-	 * as full as possible, the only time when it will be empty is when
-	 * all the jobs which need running have been run, so that is the end
-	 * condition of this loop. Note that the Job module will exit if
-	 * there were any errors unless the keepgoing flag was given.
-	 */
+	(void)MakeStartJobs();
 	while (!Lst_IsEmpty(&toBeMade) || jobTokensRunning > 0) {
 		Job_CatchOutput();
 		(void)MakeStartJobs();
@@ -1473,13 +1406,9 @@ Make_Run(GNodeList *targs)
 
 	errors = Job_Finish();
 
-	/*
-	 * Print the final status of each target. E.g. if it wasn't made
-	 * because some inferior reported an error.
-	 */
 	DEBUG1(MAKE, "done: errors %d\n", errors);
 	if (errors == 0) {
-		MakePrintStatusList(targs, &errors);
+		MakePrintStatusList(targets, &errors);
 		if (DEBUG(MAKE)) {
 			debug_printf("done: errors %d\n", errors);
 			if (errors > 0)
diff --git a/make.h b/make.h
index 50360d4168b2..405f03144b69 100644
--- a/make.h
+++ b/make.h
@@ -1,4 +1,4 @@
-/*	$NetBSD: make.h,v 1.352 2025/03/30 21:24:57 sjg Exp $	*/
+/*	$NetBSD: make.h,v 1.360 2025/06/13 18:31:08 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -517,7 +517,7 @@ typedef struct GNode {
 	struct GNode *centurion;
 
 	/* Last time (sequence number) we tried to make this node */
-	unsigned int checked_seqno;
+	unsigned checked_seqno;
 
 	/*
 	 * The "local" variables that are specific to this target and this
@@ -840,7 +840,7 @@ void Compat_MakeAll(GNodeList *);
 void Compat_Make(GNode *, GNode *);
 
 /* cond.c */
-extern unsigned int cond_depth;
+extern unsigned cond_depth;
 CondResult Cond_EvalCondition(const char *) MAKE_ATTR_USE;
 CondResult Cond_EvalLine(const char *) MAKE_ATTR_USE;
 Guard *Cond_ExtractGuard(const char *) MAKE_ATTR_USE;
@@ -886,6 +886,7 @@ void JobReapChild(pid_t, int, bool);
 void Main_ParseArgLine(const char *);
 int Cmd_Argv(const char *, size_t, const char **, size_t, char *, size_t, bool, bool);
 char *Cmd_Exec(const char *, char **) MAKE_ATTR_USE;
+void Var_ExportStackTrace(const char *, const char *);
 void Error(const char *, ...) MAKE_ATTR_PRINTFLIKE(1, 2);
 void Fatal(const char *, ...) MAKE_ATTR_PRINTFLIKE(1, 2) MAKE_ATTR_DEAD;
 void Punt(const char *, ...) MAKE_ATTR_PRINTFLIKE(1, 2) MAKE_ATTR_DEAD;
@@ -905,6 +906,8 @@ void Parse_End(void);
 #endif
 
 void PrintLocation(FILE *, bool, const GNode *);
+const char *GetParentStackTrace(void);
+char *GetStackTrace(bool);
 void PrintStackTrace(bool);
 void Parse_Error(ParseErrorLevel, const char *, ...) MAKE_ATTR_PRINTFLIKE(2, 3);
 bool Parse_VarAssign(const char *, bool, GNode *) MAKE_ATTR_USE;
@@ -912,7 +915,7 @@ void Parse_File(const char *, int);
 void Parse_PushInput(const char *, unsigned, unsigned, Buffer,
 		     struct ForLoop *);
 void Parse_MainName(GNodeList *);
-unsigned int CurFile_CondMinDepth(void) MAKE_ATTR_USE;
+unsigned CurFile_CondMinDepth(void) MAKE_ATTR_USE;
 void Parse_GuardElse(void);
 void Parse_GuardEndif(void);
 
@@ -1079,7 +1082,9 @@ void Global_Append(const char *, const char *);
 void Global_Delete(const char *);
 void Global_Set_ReadOnly(const char *, const char *);
 
-bool EvalStack_PrintDetails(void) MAKE_ATTR_USE;
+void EvalStack_PushMakeflags(const char *);
+void EvalStack_Pop(void);
+bool EvalStack_Details(Buffer *buf) MAKE_ATTR_USE;
 
 /* util.c */
 typedef void (*SignalProc)(int);
@@ -1093,7 +1098,7 @@ time_t Make_Recheck(GNode *) MAKE_ATTR_USE;
 void Make_HandleUse(GNode *, GNode *);
 void Make_Update(GNode *);
 void GNode_SetLocalVars(GNode *);
-bool Make_Run(GNodeList *);
+bool Make_MakeParallel(GNodeList *);
 bool shouldDieQuietly(GNode *, int) MAKE_ATTR_USE;
 void PrintOnError(GNode *, const char *);
 void Main_ExportMAKEFLAGS(bool);
@@ -1102,6 +1107,7 @@ int mkTempFile(const char *, char *, size_t) MAKE_ATTR_USE;
 void AppendWords(StringList *, char *);
 void GNode_FprintDetails(FILE *, const char *, const GNode *, const char *);
 bool GNode_ShouldExecute(GNode *gn) MAKE_ATTR_USE;
+char *GNodeType_ToString(GNodeType);
 
 #ifndef HAVE_STRLCPY
 size_t strlcpy(char *, const char *, size_t);
@@ -1208,6 +1214,8 @@ ch_isdigit(char ch) { return isdigit((unsigned char)ch) != 0; }
 MAKE_INLINE bool MAKE_ATTR_USE
 ch_islower(char ch) { return islower((unsigned char)ch) != 0; }
 MAKE_INLINE bool MAKE_ATTR_USE
+ch_isprint(char ch) { return isprint((unsigned char)ch) != 0; }
+MAKE_INLINE bool MAKE_ATTR_USE
 ch_isspace(char ch) { return isspace((unsigned char)ch) != 0; }
 MAKE_INLINE bool MAKE_ATTR_USE
 ch_isupper(char ch) { return isupper((unsigned char)ch) != 0; }
diff --git a/make_malloc.c b/make_malloc.c
index ea347e0ec2ca..d7a735b8b08e 100644
--- a/make_malloc.c
+++ b/make_malloc.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: make_malloc.c,v 1.26 2022/01/07 08:30:04 rillig Exp $	*/
+/*	$NetBSD: make_malloc.c,v 1.27 2025/06/12 18:51:05 rillig Exp $	*/
 
 /*
  * Copyright (c) 2009 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
 
 #include "make.h"
 
-MAKE_RCSID("$NetBSD: make_malloc.c,v 1.26 2022/01/07 08:30:04 rillig Exp $");
+MAKE_RCSID("$NetBSD: make_malloc.c,v 1.27 2025/06/12 18:51:05 rillig Exp $");
 
 #ifndef USE_EMALLOC
 
@@ -38,7 +38,7 @@ MAKE_RCSID("$NetBSD: make_malloc.c,v 1.26 2022/01/07 08:30:04 rillig Exp $");
 static MAKE_ATTR_DEAD void
 enomem(void)
 {
-	(void)fprintf(stderr, "%s: %s.\n", progname, strerror(ENOMEM));
+	(void)fprintf(stderr, "%s: %s\n", progname, strerror(errno));
 	exit(2);
 }
 
diff --git a/meta.c b/meta.c
index 7e876e745806..5d8d17f19700 100644
--- a/meta.c
+++ b/meta.c
@@ -1,4 +1,4 @@
-/*      $NetBSD: meta.c,v 1.211 2025/04/11 17:33:47 rillig Exp $ */
+/*      $NetBSD: meta.c,v 1.215 2025/06/13 06:13:19 rillig Exp $ */
 
 /*
  * Implement 'meta' mode.
@@ -52,6 +52,7 @@ char * dirname(char *);
 #include "make.h"
 #include "dir.h"
 #include "job.h"
+#include "meta.h"
 
 #ifdef USE_FILEMON
 #include "filemon/filemon.h"
@@ -646,7 +647,7 @@ MAKE_INLINE BuildMon *
 BM(Job *job)
 {
 
-	return ((job != NULL) ? &job->bm : &Mybm);
+	return job != NULL ? Job_BuildMon(job) : &Mybm;
 }
 
 /*
@@ -748,7 +749,7 @@ meta_job_error(Job *job, GNode *gn, bool ignerr, int status)
 
     pbm = BM(job);
     if (job != NULL && gn == NULL)
-	    gn = job->node;
+	    gn = Job_Node(job);
     if (pbm->mfp != NULL) {
 	fprintf(pbm->mfp, "\n*** Error code %d%s\n",
 		status, ignerr ? "(ignored)" : "");
@@ -756,7 +757,7 @@ meta_job_error(Job *job, GNode *gn, bool ignerr, int status)
     if (gn != NULL)
 	Global_Set(".ERROR_TARGET", GNode_Path(gn));
     if (getcwd(cwd, sizeof cwd) == NULL)
-	Punt("Cannot get cwd: %s", strerror(errno));
+	Punt("getcwd: %s", strerror(errno));
 
     Global_Set(".ERROR_CWD", cwd);
     if (pbm->meta_fname[0] != '\0') {
@@ -766,7 +767,7 @@ meta_job_error(Job *job, GNode *gn, bool ignerr, int status)
 }
 
 void
-meta_job_output(Job *job, char *cp, const char *nl)
+meta_job_output(Job *job, const char *cp)
 {
     BuildMon *pbm;
 
@@ -777,15 +778,10 @@ meta_job_output(Job *job, char *cp, const char *nl)
 	    static size_t meta_prefix_len;
 
 	    if (meta_prefix == NULL) {
-		char *cp2;
-
 		meta_prefix = Var_Subst("${" MAKE_META_PREFIX "}",
 					SCOPE_GLOBAL, VARE_EVAL);
 		/* TODO: handle errors */
-		if ((cp2 = strchr(meta_prefix, '$')) != NULL)
-		    meta_prefix_len = (size_t)(cp2 - meta_prefix);
-		else
-		    meta_prefix_len = strlen(meta_prefix);
+		meta_prefix_len = strcspn(meta_prefix, "$");
 	    }
 	    if (strncmp(cp, meta_prefix, meta_prefix_len) == 0) {
 		cp = strchr(cp + 1, '\n');
@@ -794,7 +790,7 @@ meta_job_output(Job *job, char *cp, const char *nl)
 		cp++;
 	    }
 	}
-	fprintf(pbm->mfp, "%s%s", cp, nl);
+	fprintf(pbm->mfp, "%s", cp);
     }
 }
 
@@ -1643,7 +1639,7 @@ meta_compat_start(void)
     }
 #endif
     if (pipe(childPipe) < 0)
-	Punt("Cannot create pipe: %s", strerror(errno));
+	Punt("pipe: %s", strerror(errno));
     /* Set close-on-exec flag for both */
     (void)fcntl(childPipe[0], F_SETFD, FD_CLOEXEC);
     (void)fcntl(childPipe[1], F_SETFD, FD_CLOEXEC);
@@ -1707,7 +1703,7 @@ meta_compat_parent(pid_t child)
 	    fwrite(buf, 1, (size_t)nread, stdout);
 	    fflush(stdout);
 	    buf[nread] = '\0';
-	    meta_job_output(NULL, buf, "");
+	    meta_job_output(NULL, buf);
 	} while (false);
 	if (metafd != -1 && FD_ISSET(metafd, &readfds) != 0) {
 	    if (meta_job_event(NULL) <= 0)
diff --git a/meta.h b/meta.h
index 5d247422ef8c..a7478cbc3e5d 100644
--- a/meta.h
+++ b/meta.h
@@ -1,4 +1,4 @@
-/*      $NetBSD: meta.h,v 1.11 2021/12/15 09:53:41 rillig Exp $ */
+/*      $NetBSD: meta.h,v 1.13 2025/06/13 06:13:19 rillig Exp $ */
 
 /*
  * Things needed for 'meta' mode.
@@ -49,7 +49,7 @@ void meta_job_parent(struct Job *, pid_t);
 int  meta_job_fd(struct Job *) MAKE_ATTR_USE;
 int  meta_job_event(struct Job *) MAKE_ATTR_USE;
 void meta_job_error(struct Job *, GNode *, bool, int);
-void meta_job_output(struct Job *, char *, const char *);
+void meta_job_output(struct Job *, const char *);
 int  meta_cmd_finish(void *);
 int  meta_job_finish(struct Job *);
 bool meta_oodate(GNode *, bool) MAKE_ATTR_USE;
diff --git a/mk/ChangeLog b/mk/ChangeLog
index c457d3aab9c2..1822f917a138 100644
--- a/mk/ChangeLog
+++ b/mk/ChangeLog
@@ -1,3 +1,43 @@
+2025-05-28  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* install-mk (MK_VERSION): 20250528
+
+	* add dirdeps2dplibs.mk
+
+2025-05-18  Simon J Gerraty  <sjg@beast.crufty.net>
+
+	* install-mk (MK_VERSION): 20250518
+
+	* meta.autodep.mk (META_FILES): re-work to fix filtering.
+	if OPTIMIZE_OBJECT_META_FILES==yes
+	provide a default META_FILE_OBJ_FILTER that selects a valid
+	.SUFFIX to match *o.meta, there's no guarantee that it will be as
+	simple as .o or .So etc.
+	We have to defer evaluation until the target script is run
+	for any of these filters to have any effect.
+	Use :S,${.OBJDIR}/,, rather than :T incase there are objects
+	in sub-dirs.
+
+	* lib.mk: leverage ${.SUFFIXES} when setting dependencies.
+
+	* add UPDATE_DEPENDFILE as a dependent option - follows
+	DIRDEPS_BUILD and use MK_UPDATE_DEPENDFILE as default for
+	UPDATE_DEPENDFILE when we think it should be yes.
+	This allows override with -DWITH[OUT]_UPDATE_DEPENDFILE
+	without overriding UPDATE_DEPENDFILE directly - which can lead to
+	trouble.
+
+2025-05-16  Simon J Gerraty  <sjg@beast.crufty.net>
+	
+	* install-mk (MK_VERSION): 20250515
+
+	* meta2deps.py: resolve the target of a Move or Link first
+	and track the last path resolved, then if the src is a relative
+	path we can easily use that last path to resolve the src correctly.
+
+	* meta2deps.sh: for a Move or Link add the dir of target path to
+	the list used to resolve the src path.
+
 2025-04-18  Simon J Gerraty  <sjg@beast.crufty.net>
 
 	* init.mk: include Skipping ${RELDIR} when _SKIP_BUILD is not empty.
diff --git a/mk/FILES b/mk/FILES
index 85d8b15dbd44..d036d017c9ce 100644
--- a/mk/FILES
+++ b/mk/FILES
@@ -2,25 +2,32 @@ ChangeLog
 FILES
 LICENSE
 README
+auto.dep.mk
 auto.obj.mk
 autoconf.mk
 autodep.mk
-auto.dep.mk
 cc-wrap.mk
 ccm.dep.mk
 compiler.mk
 cython.mk
 dep.mk
+dirdeps-cache-update.mk
+dirdeps-options.mk
+dirdeps-targets.mk
+dirdeps.mk
+dirdeps2dplibs.mk
 doc.mk
 dpadd.mk
 files.mk
 final.mk
+gendirdeps.mk
 genfiles.mk
 host-target.mk
 host.libnames.mk
 inc.mk
 init.mk
 install-mk
+install-new.mk
 install-sh
 java.mk
 jobs.mk
@@ -31,6 +38,12 @@ libs.mk
 links.mk
 man.mk
 manifest.mk
+meta.autodep.mk
+meta.stage.mk
+meta.subdir.mk
+meta.sys.mk
+meta2deps.py
+meta2deps.sh
 mk-files.txt
 mkopt.sh
 newlog.sh
@@ -50,11 +63,11 @@ srctop.mk
 stage-install.sh
 subdir.mk
 suffixes.mk
-sys.mk
 sys.clean-env.mk
 sys.debug.mk
 sys.dependfile.mk
 sys.dirdeps.mk
+sys.mk
 sys.vars.mk
 sys/AIX.mk
 sys/Cygwin.mk
@@ -73,15 +86,3 @@ target-flags.mk
 warnings.mk
 whats.mk
 yacc.mk
-dirdeps.mk
-dirdeps-cache-update.mk
-dirdeps-options.mk
-dirdeps-targets.mk
-gendirdeps.mk
-install-new.mk
-meta2deps.py
-meta2deps.sh
-meta.sys.mk
-meta.autodep.mk
-meta.stage.mk
-meta.subdir.mk
diff --git a/mk/auto.obj.mk b/mk/auto.obj.mk
index 9ae7ebe3af56..4b8c5325b71f 100644
--- a/mk/auto.obj.mk
+++ b/mk/auto.obj.mk
@@ -1,8 +1,8 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# $Id: auto.obj.mk,v 1.19 2025/03/27 15:51:06 sjg Exp $
+# $Id: auto.obj.mk,v 1.20 2025/05/17 15:29:55 sjg Exp $
 #
-#	@(#) Copyright (c) 2004, Simon J. Gerraty
+#	@(#) Copyright (c) 2004-2025, Simon J. Gerraty
 #
 #	This file is provided in the hope that it will
 #	be of use.  There is absolutely NO WARRANTY.
diff --git a/mk/dirdeps2dplibs.mk b/mk/dirdeps2dplibs.mk
new file mode 100644
index 000000000000..cecf70be7477
--- /dev/null
+++ b/mk/dirdeps2dplibs.mk
@@ -0,0 +1,35 @@
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# $Id: dirdeps2dplibs.mk,v 1.3 2025/05/29 18:32:53 sjg Exp $
+
+# DIRDEPS generally reflects things *actually used* by RELDIR.
+# dirdeps2dplibs allows us to turn DIRDEPS into a DPLIBS list
+# The order will however be sorted, so some
+# manual tweaking may be needed.
+#
+
+dirdeps2dplibs:
+
+.if ${.MAKE.LEVEL} > 0
+# for customization
+.-include <local.dirdeps2dplibs.mk>
+
+_DEPENDFILE ?= ${.MAKE.DEPENDFILE}
+
+.dinclude "${_DEPENDFILE}"
+
+INCS_DIRS += h include incs
+DIRDEPS2DPLIBS_FILTER += C;/(${INCS_DIRS:O:u:ts|})(\.common.*)*$$;;
+
+dirdeps2dplibs:
+	@echo
+.if ${DEBUG_DIRDEPS2DPLIBS:Uno:@x@${RELDIR:M$x}@} != ""
+	@echo "# DIRDEPS=${DIRDEPS:M*lib*}"
+.endif
+	@echo -n 'DPLIBS += \'; \
+	echo '${DIRDEPS:M*lib*:${DIRDEPS2DPLIBS_FILTER:ts:}:T:O:u:tu:@d@${.newline}${.tab}_{LIB${d:S,^LIB,,}} \\@}' | \
+	sed 's,_{,$${,g'; \
+	echo
+
+
+.endif
diff --git a/mk/gendirdeps.mk b/mk/gendirdeps.mk
index 53e736da3391..b52c9ca0eba3 100644
--- a/mk/gendirdeps.mk
+++ b/mk/gendirdeps.mk
@@ -1,8 +1,8 @@
-# $Id: gendirdeps.mk,v 1.51 2025/01/05 01:16:19 sjg Exp $
+# $Id: gendirdeps.mk,v 1.53 2025/05/20 17:42:49 sjg Exp $
 
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# Copyright (c) 2011-2020, Simon J. Gerraty
+# Copyright (c) 2011-2025, Simon J. Gerraty
 # Copyright (c) 2010-2018, Juniper Networks, Inc.
 # All rights reserved.
 #
@@ -76,6 +76,12 @@
 # 
 .MAIN: all
 
+.if ${DEBUG_GENDIRDEPS:Uno:@m@${RELDIR:M$m}@} != ""
+_debug.gendirdeps = 1
+.else
+_debug.gendirdeps = 0
+.endif
+
 # keep this simple
 .MAKE.MODE = compat
 
@@ -108,6 +114,9 @@ META_FILES += ${META_XTRAS:N\*.meta}
 .endif
 
 .if !empty(META_FILES)
+.if ${_debug.gendirdeps} && ${DEBUG_GENDIRDEPS:Mmeta*} != ""
+.info ${RELDIR}: META_FILES=${META_FILES}
+.endif
 
 .if ${.MAKE.LEVEL} > 0 && !empty(GENDIRDEPS_FILTER)
 # so we can compare below
@@ -146,7 +155,7 @@ GENDIRDEPS_FILTER += ${GENDIRDEPS_FILTER_VARS:@v@S,/${$v}/,/_{${v}}/,@:NS,//,*:u
 META2DEPS ?= ${.PARSEDIR}/meta2deps.sh
 META2DEPS := ${META2DEPS}
 
-.if ${DEBUG_GENDIRDEPS:Uno:@x@${RELDIR:M$x}@} != "" && ${DEBUG_GENDIRDEPS:Uno:Mmeta2d*} != ""
+.if ${_debug.gendirdeps} && ${DEBUG_GENDIRDEPS:Mmeta2d*} != ""
 _time = time
 _sh_x = sh -x
 _py_d = -ddd
@@ -260,7 +269,7 @@ dpadd_dir_list += ${f:H:tA}
 ddeps != cat ${ddep_list:O:u} | ${META2DEPS_FILTER} ${_skip_gendirdeps} \
 	sed ${GENDIRDEPS_SEDCMDS}
 
-.if ${DEBUG_GENDIRDEPS:Uno:@x@${RELDIR:M$x}@} != ""
+.if ${_debug.gendirdeps}
 .info ${RELDIR}: raw_dir_list='${dir_list}'
 .info ${RELDIR}: ddeps='${ddeps}'
 .endif
@@ -294,7 +303,7 @@ skip_ql= ${SRCTOP}* ${_objtops:@o@$o*@}
 # we need := so only skip_ql to this point applies
 ql.$o := ${dir_list:${skip_ql:${M_ListToSkip}}:M$o*/*/*:C,$o([^/]+)/(.*),\2.\1,:S,.${HOST_TARGET},.host,}
 qualdir_list += ${ql.$o}
-.if ${DEBUG_GENDIRDEPS:Uno:@x@${RELDIR:M$x}@} != ""
+.if ${_debug.gendirdeps}
 .info ${RELDIR}: o=$o ${ql.$o qualdir_list:L:@v@$v=${$v}@}
 .endif
 skip_ql+= $o*
@@ -323,7 +332,7 @@ DIRDEPS += \
 GENDIRDEPS_FILTER_MASK += @CMNS
 DIRDEPS := ${DIRDEPS:${GENDIRDEPS_FILTER:UNno:M[${GENDIRDEPS_FILTER_MASK:O:u:ts}]*:ts:}:C,//+,/,g:O:u}
 
-.if ${DEBUG_GENDIRDEPS:Uno:@x@${RELDIR:M$x}@} != ""
+.if ${_debug.gendirdeps}
 .info ${RELDIR}: M2D_OBJROOTS=${M2D_OBJROOTS}
 .info ${RELDIR}: M2D_EXCLUDES=${M2D_EXCLUDES}
 .info ${RELDIR}: dir_list='${dir_list}'
diff --git a/mk/install-mk b/mk/install-mk
index de5056a37042..8d354de17cb9 100755..100644
--- a/mk/install-mk
+++ b/mk/install-mk
@@ -59,7 +59,7 @@
 #       Simon J. Gerraty <sjg@crufty.net>
 
 # RCSid:
-#	$Id: install-mk,v 1.264 2025/03/26 18:30:18 sjg Exp $
+#	$Id: install-mk,v 1.266 2025/05/29 01:48:06 sjg Exp $
 #
 #	@(#) Copyright (c) 1994-2025 Simon J. Gerraty
 #
@@ -74,7 +74,7 @@
 #	sjg@crufty.net
 #
 
-MK_VERSION=20250326
+MK_VERSION=20250528
 OWNER=
 GROUP=
 MODE=444
diff --git a/mk/lib.mk b/mk/lib.mk
index 3f6a749a12d1..708a2a1994cc 100644
--- a/mk/lib.mk
+++ b/mk/lib.mk
@@ -1,4 +1,4 @@
-# $Id: lib.mk,v 1.85 2024/12/12 19:56:36 sjg Exp $
+# $Id: lib.mk,v 1.86 2025/05/20 17:19:37 sjg Exp $
 
 # should be set properly in sys.mk
 _this ?= ${.PARSEFILE:S,bsd.,,}
@@ -396,7 +396,7 @@ realbuild: ${_LIBS}
 all: _SUBDIRUSE
 
 .for s in ${SRCS:${OBJS_SRCS_PRE_FILTER:ts:}:M*/*}
-${.o .po .lo:L:@o@${s:${OBJS_SRCS_FILTER:ts:}}$o@}: $s
+${.SUFFIXES:U.o .po .lo:M*o:@o@${s:${OBJS_SRCS_FILTER:ts:}}$o@}: $s
 .endfor
 
 OBJS_SRCS = ${SRCS:${OBJS_SRCS_FILTER:ts:}}
diff --git a/mk/libs.mk b/mk/libs.mk
index fef339c03bce..6814916657ec 100644
--- a/mk/libs.mk
+++ b/mk/libs.mk
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# $Id: libs.mk,v 1.7 2024/02/17 17:26:57 sjg Exp $
+# $Id: libs.mk,v 1.8 2025/05/19 19:15:22 sjg Exp $
 #
 #	@(#) Copyright (c) 2006, Simon J. Gerraty
 #
@@ -59,7 +59,7 @@ $v += ${${v}_${LIB}:U${${v}.${LIB}}}
 
 # for meta mode, there can be only one!
 .if ${LIB} == ${UPDATE_DEPENDFILE_LIB:Uno}
-UPDATE_DEPENDFILE ?= yes
+UPDATE_DEPENDFILE ?= ${MK_UPDATE_DEPENDFILE:Uyes}
 .endif
 UPDATE_DEPENDFILE ?= NO
 
diff --git a/mk/meta.autodep.mk b/mk/meta.autodep.mk
index b94891b1b93f..ce16ac843dc3 100644
--- a/mk/meta.autodep.mk
+++ b/mk/meta.autodep.mk
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# $Id: meta.autodep.mk,v 1.65 2025/03/14 20:28:42 sjg Exp $
+# $Id: meta.autodep.mk,v 1.70 2025/05/28 20:03:00 sjg Exp $
 
 #
 #	@(#) Copyright (c) 2010-2025, Simon J. Gerraty
@@ -22,6 +22,12 @@ __${_this}__: .NOTMAIN
 
 .-include <local.autodep.mk>
 
+.if ${DEBUG_AUTODEP:Uno:@m@${RELDIR:M$m}@} != ""
+_debug.autodep = 1
+.else
+_debug.autodep = 0
+.endif
+
 PICO?= .pico
 
 .if defined(SRCS)
@@ -85,9 +91,9 @@ UPDATE_DEPENDFILE = NO
 _bootstrap_dirdeps = yes
 .endif
 _bootstrap_dirdeps ?= no
-UPDATE_DEPENDFILE ?= yes
+UPDATE_DEPENDFILE ?= ${MK_UPDATE_DEPENDFILE:Uyes}
 
-.if ${DEBUG_AUTODEP:Uno:@m@${RELDIR:M$m}@} != ""
+.if ${_debug.autodep}
 .info ${_DEPENDFILE:S,${SRCTOP}/,,} update=${UPDATE_DEPENDFILE}
 .endif
 
@@ -111,7 +117,7 @@ WANT_UPDATE_DEPENDFILE ?= yes
 UPDATE_DEPENDFILE = no
 .endif
 
-.if ${DEBUG_AUTODEP:Uno:@m@${RELDIR:M$m}@} != ""
+.if ${_debug.autodep}
 .info ${_DEPENDFILE:S,${SRCTOP}/,,} update=${UPDATE_DEPENDFILE}
 .endif
 
@@ -207,7 +213,7 @@ CAT_DEPEND = /dev/null
 _depend =
 .endif
 
-.if ${DEBUG_AUTODEP:Uno:@m@${RELDIR:M$m}@} != ""
+.if ${_debug.autodep}
 .info ${_DEPENDFILE:S,${SRCTOP}/,,} _depend=${_depend}
 .endif
 
@@ -253,19 +259,33 @@ _gendirdeps_mutex = ${GENDIRDEPS_MUTEXER} ${GENDIRDEPS_MUTEX:U${_CURDIR}/Makefil
 # but we need to behave as if we did.
 # Avoid adding glob patterns to .MAKE.META.CREATED though.
 .MAKE.META.CREATED += ${META_XTRAS:N*\**:O:u}
-
-.if make(gendirdeps)
-META_FILES = *.meta
-.elif ${OPTIMIZE_OBJECT_META_FILES:Uno:tl} == "no"
-META_FILES = ${.MAKE.META.FILES:T:N.depend*:O:u}
+OPTIMIZE_OBJECT_META_FILES ?= no
+
+.if ${OPTIMIZE_OBJECT_META_FILES} == "yes"
+# If we have lots of .o.meta, ${PICO}.meta etc we need only look at one set.
+# If META_FILE_OBJ_FILTER is not already set, we default it to a
+# .SUFFIX which matches the first *o.meta.
+# There is no guarantee it will be just .o or .So etc,
+META_FILE_OBJ_FILTER ?= \
+	${.SUFFIXES:M*o:@o@${"${.MAKE.META.FILES:T:M*$o.meta:[1]}":?M*$o.meta:}@:[1]}
+.endif
+
+# parent may have set META_FILE_OBJ_FILTER
+.if ${OPTIMIZE_OBJECT_META_FILES} == "yes" || !empty(META_FILE_OBJ_FILTER)
+META_FILES = \
+	${.MAKE.META.FILES:N.depend*:N*o.meta} \
+	${.MAKE.META.FILES:${META_FILE_OBJ_FILTER}}
 .else
-# if we have 1000's of .o.meta, ${PICO}.meta etc we need only look at one set
-# it is left as an exercise for the reader to work out what this does
-META_FILES = ${.MAKE.META.FILES:T:N.depend*:N*o.meta:O:u} \
-	${.MAKE.META.FILES:T:M*.${.MAKE.META.FILES:M*o.meta:R:E:O:u:[1]}.meta:O:u}
+META_FILES = ${.MAKE.META.FILES:N.depend*}
 .endif
+# ensure this is not empty (this will sort after any M and N
+# we use S,${_OBJDIR}/,, rather than :T since some makefiles have
+# objects in subdirs
+META_FILE_FILTER += S,${_OBJDIR}/,,:O:u
+# we have to defer evaluation until the target script runs
+GENDIRDEPS_ENV += META_FILES="${META_FILES:${META_FILE_FILTER:O:u:ts:}}}"
 
-.if ${DEBUG_AUTODEP:Uno:@m@${RELDIR:M$m}@} != ""
+.if ${_debug.autodep}
 .info ${_DEPENDFILE:S,${SRCTOP}/,,}: ${_depend} ${.PARSEDIR}/gendirdeps.mk ${META2DEPS} xtras=${META_XTRAS}
 .endif
 
@@ -276,9 +296,6 @@ META_FILES = ${.MAKE.META.FILES:T:N.depend*:N*o.meta:O:u} \
 .if !empty(GENDIRDEPS_FILTER)
 .export GENDIRDEPS_FILTER
 .endif
-# export to avoid blowing command line limit
-META_FILES := ${META_XTRAS:U:O:u} ${META_FILES:U:T:O:u:${META_FILE_FILTER:ts:}}
-.export META_FILES
 .endif
 
 _this_dir := ${_PARSEDIR}
@@ -301,7 +318,7 @@ ${_DEPENDFILE}: ${_depend} ${.PARSEDIR}/gendirdeps.mk  ${META2DEPS} $${.MAKE.MET
 	@(cd . && ${GENDIRDEPS_ENV} \
 	SKIP_GENDIRDEPS='${SKIP_GENDIRDEPS:O:u}' \
 	DPADD='${FORCE_DPADD:O:u}' ${_gendirdeps_mutex} \
-	${.MAKE} -f gendirdeps.mk RELDIR=${RELDIR} _DEPENDFILE=${_DEPENDFILE})
+	${.MAKE} -B -f gendirdeps.mk RELDIR=${RELDIR} _DEPENDFILE=${_DEPENDFILE})
 	@test -s $@ && touch $@; :
 .endif
 
diff --git a/mk/meta2deps.py b/mk/meta2deps.py
index 44c752d0e7eb..70b121003988 100755
--- a/mk/meta2deps.py
+++ b/mk/meta2deps.py
@@ -39,9 +39,9 @@ We only pay attention to a subset of the information in the
 SPDX-License-Identifier: BSD-2-Clause
 
 RCSid:
-	$Id: meta2deps.py,v 1.50 2024/09/27 00:08:36 sjg Exp $
+	$Id: meta2deps.py,v 1.51 2025/05/16 20:03:43 sjg Exp $
 
-	Copyright (c) 2011-2020, Simon J. Gerraty
+	Copyright (c) 2011-2025, Simon J. Gerraty
 	Copyright (c) 2011-2017, Juniper Networks, Inc.
 	All rights reserved.
 
@@ -543,8 +543,8 @@ class MetaFile:
             if w[0] in 'ML':
                 # these are special, tread src as read and
                 # target as write
-                self.parse_path(w[2].strip("'"), cwd, 'R', w)
                 self.parse_path(w[3].strip("'"), cwd, 'W', w)
+                self.parse_path(w[2].strip("'"), cwd, 'R', w)
                 continue
             elif w[0] in 'ERWS':
                 path = w[2]
@@ -611,9 +611,19 @@ class MetaFile:
                 return
         # we don't want to resolve the last component if it is
         # a symlink
-        path = resolve(path, cwd, self.last_dir, self.debug, self.debug_out)
-        if not path:
-            return
+        npath = resolve(path, cwd, self.last_dir, self.debug, self.debug_out)
+        if not npath:
+            if len(w) > 3 and w[0] in 'ML' and op == 'R' and path.startswith('../'):
+                # we already resolved the target of the M/L
+                # so it makes sense to try and resolve relative to that dir.
+                if os.path.isdir(self.last_path):
+                    dir = self.last_path
+                else:
+                    dir,junk = os.path.split(self.last_path)
+                npath = resolve(path, cwd, dir, self.debug, self.debug_out)
+            if not npath:
+                return
+        path = npath
         dir,base = os.path.split(path)
         if dir in self.seen:
             if self.debug > 2:
@@ -631,6 +641,7 @@ class MetaFile:
             rdir = None
         # now put path back together
         path = '/'.join([dir,base])
+        self.last_path = path
         if self.debug > 1:
             print("raw=%s rdir=%s dir=%s path=%s" % (w[2], rdir, dir, path), file=self.debug_out)
         if op in 'RWS':
diff --git a/mk/meta2deps.sh b/mk/meta2deps.sh
index f031165e1d32..4af15971b84f 100755
--- a/mk/meta2deps.sh
+++ b/mk/meta2deps.sh
@@ -77,10 +77,11 @@
 
 
 # RCSid:
-#	$Id: meta2deps.sh,v 1.21 2024/02/17 17:26:57 sjg Exp $
+#	$Id: meta2deps.sh,v 1.22 2025/05/16 20:03:43 sjg Exp $
 
 # SPDX-License-Identifier: BSD-2-Clause
 #
+# Copyright (c) 2011-2025, Simon J. Gerraty
 # Copyright (c) 2010-2013, Juniper Networks, Inc.
 # All rights reserved.
 #
@@ -252,9 +253,9 @@ meta2deps() {
     esac 2> /dev/null |
     sed -e 's,^CWD,C C,;/^[#CREFLMVX] /!d' -e "s,',,g" |
     $_excludes | ( version=no epids= xpids= eof_token=no
-    while read op pid path junk
+    while read op pid path path2
     do
-	: op=$op pid=$pid path=$path
+	: op=$op pid=$pid path=$path path2=$path2
 	# we track cwd and ldir (of interest) per pid
 	# CWD is bmake's cwd
 	case "$lpid,$pid" in
@@ -321,9 +322,14 @@ meta2deps() {
 	    $src_re|$obj_re) ;;
 	    /*/stage/*) ;;
 	    /*) continue;;
-	    *)	for path in $ldir/$path $cwd/$path
+	    *)
+		rlist="$ldir/$path $cwd/$path"
+		case "$op,$path" in
+		[ML],../*) rlist="$rlist $path2/$path `dirname $path2`/$path";;
+		esac
+		for path in $rlist
 		do
-			test -e $path && break
+		    test -e $path && break
 		done
 		dir=${path%/*}
 		;;
diff --git a/mk/mkopt.sh b/mk/mkopt.sh
index 24320c257250..ec425440570b 100644
--- a/mk/mkopt.sh
+++ b/mk/mkopt.sh
@@ -2,9 +2,9 @@
 
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# $Id: mkopt.sh,v 1.16 2024/02/17 17:26:57 sjg Exp $
+# $Id: mkopt.sh,v 1.17 2025/05/22 22:35:14 sjg Exp $
 #
-#	@(#) Copyright (c) 2014-2022, Simon J. Gerraty
+#	@(#) Copyright (c) 2014-2025, Simon J. Gerraty
 #
 #	This file is provided in the hope that it will
 #	be of use.  There is absolutely NO WARRANTY.
@@ -89,18 +89,19 @@ _mk_opts_defaults() {
 # _mk_cmdline_opts opt ...
 # look at the command line (saved in _cmdline)
 # to see any options we care about are being set with -DWITH*
-# or MK_*= if 'opt' is '*' then all options are of interest.
+# or MK_*= and WITH[OUT]_*= if 'opt' is '*' then all options are of interest.
 _cmdline="$0 $@"
 _mk_cmdline_opts() {
     for _x in $_cmdline
     do
 	case "$_x" in
-	-DWITH*|${_MKOPT_PREFIX:-MK_}*)
+	-DWITH*|WITH*=*|${_MKOPT_PREFIX:-MK_}*=*)
 	    for _o in "$@"
 	    do
 		case "$_x" in
 		-DWITH_$_o|-DWITHOUT_$_o) eval ${_x#-D}=1;;
 		-DWITH_$_o=*|-DWITHOUT_$_o=*) eval ${_x#-D};;
+		WITH_$_o=*|WITHOUT_$_o=*) eval "$_x";;
 		${_MKOPT_PREFIX:-MK_}$_o=*) eval "$_x";;
 		esac
 	    done
diff --git a/mk/newlog.sh b/mk/newlog.sh
index 5c65e5dd5fb6..fbf347ee2746 100755
--- a/mk/newlog.sh
+++ b/mk/newlog.sh
@@ -15,11 +15,12 @@
 #
 #	-C "compress"
 #		Compact old logs (other than .0) with "compress"
-#		(default is 'gzip' or 'compress' if no 'gzip').
+#		(default is "$NEWLOG_COMPRESS" 'gzip' or 'compress' if
+#		no 'gzip').
 #
 #	-E "ext"
 #		If "compress" produces a file extention other than
-#		'.Z' or '.gz' we need to know.
+#		'.Z' or '.gz' we need to know ("$NEWLOG_EXT").
 #
 #	-G "gens"
 #		"gens" is a comma separated list of "log":"num" pairs
@@ -39,6 +40,7 @@
 #		uniquely name it when using the '-S' option.
 #		If a "log" is saved more than once per second we add
 #		an extra suffix of our process-id.
+#		The default can be set in the env via "$NEWLOG_FMT".
 #
 #	-d	The "log" to be rotated/saved is a directory.
 #		We leave the mode of old directories alone.
@@ -50,21 +52,24 @@
 #		Set the group of "log" to "group".
 #
 #	-m "mode"
-#		Set the mode of "log".
+#		Set the mode of "log" ("$NEWLOG_MODE").
 #
 #	-M "mode"
-#		Set the mode of old logs (default 444).
+#		Set the mode of old logs (default "$NEWLOG_OLD_MODE"
+#		or 444).
 #
 #	-n "num"
-#		Keep "num" generations of "log".
+#		Keep "num" generations of "log" ("$NEWLOG_NUM").
 #
 #	-o "owner"
 #		Set the owner of "log".
 #
-#	Regardless of whether '-R' or '-S' is provided, we attempt to
-#	choose the correct behavior based on observation of "log.0" if
-#	it exists; if it is a symbolic link, we save, otherwise
-#	we rotate.
+#	The default method for dealing with logs can be set via
+#	"$NEWLOG_METHOD" ('save' or 'rotate').
+#	Regardless of "$NEWLOG_METHOD" or whether '-R' or '-S' is
+#	provided, we attempt to choose the correct behavior based on
+#	observation of "log.0" if it exists; if it is a symbolic link,
+#	we 'save', otherwise we 'rotate'.
 #
 # BUGS:
 #	'Newlog.sh' tries to avoid being fooled by symbolic links, but
@@ -76,11 +81,11 @@
 #
 
 # RCSid:
-#	$Id: newlog.sh,v 1.27 2024/02/17 17:26:57 sjg Exp $
+#	$Id: newlog.sh,v 1.30 2025/06/01 05:07:48 sjg Exp $
 #
 #	SPDX-License-Identifier: BSD-2-Clause
 #
-#	@(#) Copyright (c) 1993-2016 Simon J. Gerraty
+#	@(#) Copyright (c) 1993-2025 Simon J. Gerraty
 #
 #	This file is provided in the hope that it will
 #	be of use.  There is absolutely NO WARRANTY.
@@ -168,6 +173,10 @@ get_mode() {
 		$STAT -f %Op $1 | sed 's,.*\(....\),\1,'
 		return
 		;;
+	Linux,$STAT)		# works on Ubuntu
+		$STAT -c %a $1 2> /dev/null &&
+		return
+		;;
 	esac
 	# fallback to find
 	fmode `find $1 -ls -prune | awk '{ print $3 }'`
@@ -179,21 +188,33 @@ get_mtime_suffix() {
 		$STAT -t "${2:-$opt_f}" -f %Sm $1
 		return
 		;;
+	Linux,*)		# works on Ubuntu
+		mtime=`$STAT --format=%Y $1 2> /dev/null`
+		if [ ${mtime:-0} -gt 1 ]; then
+			date --date=@$mtime "+${2:-$opt_f}" 2> /dev/null &&
+			return
+		fi
+		;;
 	esac
 	# this will have to do
 	date "+${2:-$opt_f}"
 }
 
 case /$0 in
-*/newlog*) rotate_func=rotate_log;;
+*/newlog*) rotate_func=${NEWLOG_METHOD:-rotate_log};;
 */save*) rotate_func=save_log;;
-*) rotate_func=rotate_log;;
+*) rotate_func=${NEWLOG_METHOD:-rotate_log};;
+esac
+case "$rotate_func" in
+save|rotate) rotate_func=${rotate_func}_log;;
 esac
 
-opt_n=7
-opt_m=
-opt_M=444
-opt_f=%Y%m%d.%H%M%S
+opt_C=${NEWLOG_COMPRESS}
+opt_E=${NEWLOG_EXT}
+opt_n=${NEWLOG_NUM:-7}
+opt_m=${NEWLOG_MODE}
+opt_M=${NEWLOG_OLD_MODE:-444}
+opt_f=${NEWLOG_FMT:-%Y-%m-%dT%T} # rfc3339
 opt_str=dNn:o:g:G:C:M:m:eE:f:RS
 
 . setopts.sh
@@ -241,7 +262,7 @@ case "${opt_R:-0}" in
 esac
 case "${opt_S:-0}" in
 0) ;;
-*) rotate_func=save_log opt_S=;;
+*) rotate_func=save_log;;
 esac
 
 # see whether test handles -h or -L
@@ -345,12 +366,7 @@ save_log() {
 	$ECHO rm $rm_f `'ls' -1td $log.* 2> /dev/null | sed "1,${n}d"`
 
 	mode=${opt_m:-`get_mode $log`}
-	# this is our default suffix
-	opt_S=${opt_S:-`get_mtime_suffix $log $fmt`}
-	case "$fmt" in
-	""|$opt_f) suffix=$opt_S;;
-	*) suffix=`get_mtime_suffix $log $fmt`;;
-	esac
+	suffix=`get_mtime_suffix $log $fmt`
 
 	# find a unique name to save current log as
 	for nlog in $log.$suffix $log.$suffix.$$
diff --git a/mk/progs.mk b/mk/progs.mk
index ada942db8621..fe8cad4b5c26 100644
--- a/mk/progs.mk
+++ b/mk/progs.mk
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# $Id: progs.mk,v 1.18 2024/04/09 17:18:24 sjg Exp $
+# $Id: progs.mk,v 1.19 2025/05/19 19:15:22 sjg Exp $
 #
 #	@(#) Copyright (c) 2006, Simon J. Gerraty
 #
@@ -68,7 +68,7 @@ $v += ${${v}_${PROG}:U${${v}.${PROG}}}
 
 # for meta mode, there can be only one!
 .if ${PROG} == ${UPDATE_DEPENDFILE_PROG:Uno}
-UPDATE_DEPENDFILE ?= yes
+UPDATE_DEPENDFILE ?= ${MK_UPDATE_DEPENDFILE:Uyes}
 .endif
 UPDATE_DEPENDFILE ?= NO
 
diff --git a/mk/setopts.sh b/mk/setopts.sh
index 91c65c776438..5fccb0bcb6fe 100644
--- a/mk/setopts.sh
+++ b/mk/setopts.sh
@@ -12,17 +12,17 @@
 #	This module sets shell variables for each option specified in
 #	"opt_str".
 #
-#	If the option is followed by a ``:'' it requires an argument.
+#	If the option is followed by a ':' it requires an argument.
 #	It defaults to an empty string and specifying that option on
 #	the command line overrides the current value. 
 #	
-#	If the option is followed by a ``.'' then it is treated as for
-#	``:'' except that any argument provided on the command line is
-#	appended to the current value using the value of "opt_dot" as
-#	separator (default is a space).
+#	If the option "o" is followed by a '.' then it is treated as for
+#	':' except that any argument provided on the command line is
+#	appended to the current value using the value of "opt_dot_$o"
+#	if set, or "opt_dot" as separator (default is a space).
 #
-#	If the option is followed by a ``,'' then it is treated as for
-#	a ``.'' except that the separator is "opt_comma" (default ,).
+#	If the option is followed by a ',' then it is treated as for
+#	a '.' except that the separator is "opt_comma" (default ',').
 #
 #	If the option is followed by ``='' it requires an argument
 #	of the form "var=val" which will be evaluated.
@@ -50,9 +50,9 @@
 #
 
 # RCSid:
-#	$Id: setopts.sh,v 1.13 2023/02/20 19:30:06 sjg Exp $
+#	$Id: setopts.sh,v 1.15 2025/06/01 02:10:31 sjg Exp $
 #
-#	@(#) Copyright (c) 1995-2023 Simon J. Gerraty
+#	@(#) Copyright (c) 1995-2025 Simon J. Gerraty
 #
 #	This file is provided in the hope that it will
 #	be of use.  There is absolutely NO WARRANTY.
@@ -87,7 +87,7 @@ set1opt() {
 
 	case "$opt_str" in
 	*${o}:*) eval "opt_$o=\"$a\"";;
-	*${o}.*) eval "opt_$o=\"\${opt_$o}\${opt_$o:+$opt_dot}$a\"";;
+	*${o}.*) eval "opt_$o=\"\${opt_$o}\${opt_$o:+\${opt_dot_$o:-$opt_dot}}$a\"";;
 	*${o},*) eval "opt_$o=\"\${opt_$o}\${opt_$o:+$opt_comma}$a\"";;
 	*${o}=*)
 		case "$a" in
diff --git a/mk/sys.mk b/mk/sys.mk
index cf6ef061f406..d05bd62e10c0 100644
--- a/mk/sys.mk
+++ b/mk/sys.mk
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: BSD-2-Clause
 #
-# $Id: sys.mk,v 1.61 2024/10/30 23:46:26 sjg Exp $
+# $Id: sys.mk,v 1.62 2025/05/19 19:15:22 sjg Exp $
 #
 #	@(#) Copyright (c) 2003-2023, Simon J. Gerraty
 #
@@ -101,6 +101,7 @@ OPTIONS_DEFAULT_DEPENDENT += \
 	META_MODE/DIRDEPS_BUILD \
 	STAGING/DIRDEPS_BUILD \
 	STATIC_DIRDEPS_CACHE/DIRDEPS_CACHE \
+	UPDATE_DEPENDFILE/DIRDEPS_BUILD \
 
 .-include <options.mk>
 
diff --git a/parse.c b/parse.c
index c087f24864bc..844d4db207ca 100644
--- a/parse.c
+++ b/parse.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: parse.c,v 1.743 2025/04/13 09:34:43 rillig Exp $	*/
+/*	$NetBSD: parse.c,v 1.752 2025/06/16 18:20:00 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -110,7 +110,7 @@
 #include "pathnames.h"
 
 /*	"@(#)parse.c	8.3 (Berkeley) 3/19/94"	*/
-MAKE_RCSID("$NetBSD: parse.c,v 1.743 2025/04/13 09:34:43 rillig Exp $");
+MAKE_RCSID("$NetBSD: parse.c,v 1.752 2025/06/16 18:20:00 rillig Exp $");
 
 /* Detects a multiple-inclusion guard in a makefile. */
 typedef enum {
@@ -130,7 +130,7 @@ typedef struct IncludedFile {
 	unsigned forBodyReadLines; /* the number of physical lines that have
 				 * been read from the file above the body of
 				 * the .for loop */
-	unsigned int condMinDepth; /* depth of nested 'if' directives, at the
+	unsigned condMinDepth;	/* depth of nested 'if' directives, at the
 				 * beginning of the file */
 	bool depending;		/* state of doing_depend on EOF */
 
@@ -342,7 +342,7 @@ CurFile(void)
 	return GetInclude(includes.len - 1);
 }
 
-unsigned int
+unsigned
 CurFile_CondMinDepth(void)
 {
 	return CurFile()->condMinDepth;
@@ -372,7 +372,7 @@ LoadFile(const char *path, int fd)
 		assert(buf.len < buf.cap);
 		n = read(fd, buf.data + buf.len, buf.cap - buf.len);
 		if (n < 0) {
-			Error("%s: read error: %s", path, strerror(errno));
+			Error("%s: %s", path, strerror(errno));
 			exit(2);	/* Not 1 so -q can distinguish error */
 		}
 		if (n == 0)
@@ -388,23 +388,43 @@ LoadFile(const char *path, int fd)
 	return buf;		/* may not be null-terminated */
 }
 
+const char *
+GetParentStackTrace(void)
+{
+	static bool initialized;
+	static const char *parentStackTrace;
+
+	if (!initialized) {
+		const char *env = getenv("MAKE_STACK_TRACE");
+		parentStackTrace = env == NULL ? NULL
+		    : env[0] == '\t' ? bmake_strdup(env)
+		    : strcmp(env, "yes") == 0 ? bmake_strdup("")
+		    : NULL;
+		initialized = true;
+	}
+	return parentStackTrace;
+}
+
 /*
  * Print the current chain of .include and .for directives.  In Parse_Fatal
  * or other functions that already print the location, includingInnermost
  * would be redundant, but in other cases like Error or Fatal it needs to be
  * included.
  */
-void
-PrintStackTrace(bool includingInnermost)
+char *
+GetStackTrace(bool includingInnermost)
 {
+	const char *parentStackTrace;
+	Buffer buffer, *buf = &buffer;
 	const IncludedFile *entries;
 	size_t i, n;
+	bool hasDetails;
 
-	bool hasDetails = EvalStack_PrintDetails();
-
+	Buf_Init(buf);
+	hasDetails = EvalStack_Details(buf);
 	n = includes.len;
 	if (n == 0)
-		return;
+		goto add_parent_stack_trace;
 
 	entries = GetInclude(0);
 	if (!includingInnermost && !(hasDetails && n > 1)
@@ -424,16 +444,49 @@ PrintStackTrace(bool includingInnermost)
 
 		if (entry->forLoop != NULL) {
 			char *details = ForLoop_Details(entry->forLoop);
-			debug_printf("\tin .for loop from %s:%u with %s\n",
-			    fname, entry->forHeadLineno, details);
+			Buf_AddStr(buf, "\tin .for loop from ");
+			Buf_AddStr(buf, fname);
+			Buf_AddStr(buf, ":");
+			Buf_AddInt(buf, (int)entry->forHeadLineno);
+			Buf_AddStr(buf, " with ");
+			Buf_AddStr(buf, details);
+			Buf_AddStr(buf, "\n");
 			free(details);
 		} else if (i + 1 < n && entries[i + 1].forLoop != NULL) {
 			/* entry->lineno is not a useful line number */
-		} else
-			debug_printf("\tin %s:%u\n", fname, entry->lineno);
+		} else {
+			Buf_AddStr(buf, "\tin ");
+			Buf_AddStr(buf, fname);
+			Buf_AddStr(buf, ":");
+			Buf_AddInt(buf, (int)entry->lineno);
+			Buf_AddStr(buf, "\n");
+		}
+	}
+
+add_parent_stack_trace:
+	parentStackTrace = GetParentStackTrace();
+	if ((makelevel > 0 && (n > 0 || !includingInnermost))
+	    || parentStackTrace != NULL) {
+		Buf_AddStr(buf, "\tin ");
+		Buf_AddStr(buf, progname);
+		Buf_AddStr(buf, " in directory \"");
+		Buf_AddStr(buf, curdir);
+		Buf_AddStr(buf, "\"\n");
 	}
-	if (makelevel > 0)
-		debug_printf("\tin directory %s\n", curdir);
+
+	if (parentStackTrace != NULL)
+		Buf_AddStr(buf, parentStackTrace);
+
+	return Buf_DoneData(buf);
+}
+
+void
+PrintStackTrace(bool includingInnermost)
+{
+	char *stackTrace = GetStackTrace(includingInnermost);
+	fprintf(stderr, "%s", stackTrace);
+	fflush(stderr);
+	free(stackTrace);
 }
 
 /* Check if the current character is escaped on the current line. */
@@ -547,7 +600,8 @@ ParseVErrorInternal(FILE *f, bool useVars, const GNode *gn,
 		parseErrors++;
 	}
 
-	if (level == PARSE_FATAL || DEBUG(PARSE))
+	if (level == PARSE_FATAL || DEBUG(PARSE)
+	    || (gn == NULL && includes.len == 0 /* see PrintLocation */))
 		PrintStackTrace(false);
 }
 
@@ -713,7 +767,7 @@ TryApplyDependencyOperator(GNode *gn, GNodeType op)
 		cohort->centurion = gn;
 		gn->unmade_cohorts++;
 		snprintf(cohort->cohort_num, sizeof cohort->cohort_num, "#%d",
-		    (unsigned int)gn->unmade_cohorts % 1000000);
+		    (unsigned)gn->unmade_cohorts % 1000000);
 	} else {
 		gn->type |= op;	/* preserve any previous flags */
 	}
diff --git a/suff.c b/suff.c
index c24a0ac5afdc..cfafa9ffe948 100644
--- a/suff.c
+++ b/suff.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: suff.c,v 1.383 2025/01/14 21:39:24 rillig Exp $	*/
+/*	$NetBSD: suff.c,v 1.384 2025/05/18 06:24:27 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -115,7 +115,7 @@
 #include "dir.h"
 
 /*	"@(#)suff.c	8.4 (Berkeley) 3/21/94"	*/
-MAKE_RCSID("$NetBSD: suff.c,v 1.383 2025/01/14 21:39:24 rillig Exp $");
+MAKE_RCSID("$NetBSD: suff.c,v 1.384 2025/05/18 06:24:27 rillig Exp $");
 
 typedef List SuffixList;
 typedef ListNode SuffixListNode;
@@ -1027,16 +1027,16 @@ CandidateList_AddCandidatesFor(CandidateList *list, Candidate *cand)
  * Return whether a candidate was removed.
  */
 static bool
-RemoveCandidate(CandidateList *srcs)
+RemoveCandidate(CandidateList *sources)
 {
 	CandidateListNode *ln;
 
 #ifdef DEBUG_SRC
-	debug_printf("cleaning list %p:", srcs);
-	CandidateList_PrintAddrs(srcs);
+	debug_printf("cleaning list %p:", sources);
+	CandidateList_PrintAddrs(sources);
 #endif
 
-	for (ln = srcs->first; ln != NULL; ln = ln->next) {
+	for (ln = sources->first; ln != NULL; ln = ln->next) {
 		Candidate *src = ln->datum;
 
 		if (src->numChildren == 0) {
@@ -1056,10 +1056,10 @@ RemoveCandidate(CandidateList *srcs)
 			}
 #ifdef DEBUG_SRC
 			debug_printf("free: list %p src %p:%s children %d\n",
-			    srcs, src, src->file, src->numChildren);
+			    sources, src, src->file, src->numChildren);
 			Lst_Done(&src->childrenList);
 #endif
-			Lst_Remove(srcs, ln);
+			Lst_Remove(sources, ln);
 			free(src->file);
 			free(src);
 			return true;
@@ -1067,7 +1067,7 @@ RemoveCandidate(CandidateList *srcs)
 #ifdef DEBUG_SRC
 		else {
 			debug_printf("keep: list %p src %p:%s children %d:",
-			    srcs, src, src->file, src->numChildren);
+			    sources, src, src->file, src->numChildren);
 			CandidateList_PrintAddrs(&src->childrenList);
 		}
 #endif
@@ -1076,20 +1076,20 @@ RemoveCandidate(CandidateList *srcs)
 	return false;
 }
 
-/* Find the first existing file/target in srcs. */
+/* Find the first existing file/target in sources. */
 static Candidate *
-FindThem(CandidateList *srcs, CandidateSearcher *cs)
+FindThem(CandidateList *sources, CandidateSearcher *cs)
 {
 	HashSet seen;
 
 	HashSet_Init(&seen);
 
-	while (!Lst_IsEmpty(srcs)) {
-		Candidate *src = Lst_Dequeue(srcs);
+	while (!Lst_IsEmpty(sources)) {
+		Candidate *src = Lst_Dequeue(sources);
 
 #ifdef DEBUG_SRC
 		debug_printf("remove from list %p src %p:%s\n",
-		    srcs, src, src->file);
+		    sources, src, src->file);
 #endif
 		DEBUG1(SUFF, "\ttrying %s...", src->file);
 
@@ -1116,7 +1116,7 @@ FindThem(CandidateList *srcs, CandidateSearcher *cs)
 		DEBUG0(SUFF, "not there\n");
 
 		if (HashSet_Add(&seen, src->file))
-			CandidateList_AddCandidatesFor(srcs, src);
+			CandidateList_AddCandidatesFor(sources, src);
 		else {
 			DEBUG1(SUFF, "FindThem: skipping duplicate \"%s\"\n",
 			    src->file);
@@ -1650,7 +1650,7 @@ FindDepsLib(GNode *gn)
 
 static void
 FindDepsRegularKnown(const char *name, size_t nameLen, GNode *gn,
-		     CandidateList *srcs, CandidateList *targs)
+		     CandidateList *sources, CandidateList *targets)
 {
 	SuffixListNode *ln;
 	Candidate *targ;
@@ -1665,20 +1665,20 @@ FindDepsRegularKnown(const char *name, size_t nameLen, GNode *gn,
 		targ = Candidate_New(bmake_strdup(gn->name), pref, suff, NULL,
 		    gn);
 
-		CandidateList_AddCandidatesFor(srcs, targ);
+		CandidateList_AddCandidatesFor(sources, targ);
 
 		/* Record the target so we can nuke it. */
-		Lst_Append(targs, targ);
+		Lst_Append(targets, targ);
 	}
 }
 
 static void
 FindDepsRegularUnknown(GNode *gn, const char *sopref,
-		       CandidateList *srcs, CandidateList *targs)
+		       CandidateList *sources, CandidateList *targets)
 {
 	Candidate *targ;
 
-	if (!Lst_IsEmpty(targs) || nullSuff == NULL)
+	if (!Lst_IsEmpty(targets) || nullSuff == NULL)
 		return;
 
 	DEBUG1(SUFF, "\tNo known suffix on %s. Using .NULL suffix\n", gn->name);
@@ -1693,14 +1693,14 @@ FindDepsRegularUnknown(GNode *gn, const char *sopref,
 	 * this anymore.
 	 */
 	if (Lst_IsEmpty(&gn->commands))
-		CandidateList_AddCandidatesFor(srcs, targ);
+		CandidateList_AddCandidatesFor(sources, targ);
 	else {
 		DEBUG0(SUFF, "not ");
 	}
 
 	DEBUG0(SUFF, "adding suffix rules\n");
 
-	Lst_Append(targs, targ);
+	Lst_Append(targets, targ);
 }
 
 /*
@@ -1762,12 +1762,12 @@ static void
 FindDepsRegular(GNode *gn, CandidateSearcher *cs)
 {
 	/* List of sources at which to look */
-	CandidateList srcs = LST_INIT;
+	CandidateList sources = LST_INIT;
 	/*
 	 * List of targets to which things can be transformed.
 	 * They all have the same file, but different suff and prefix fields.
 	 */
-	CandidateList targs = LST_INIT;
+	CandidateList targets = LST_INIT;
 	Candidate *bottom;	/* Start of found transformation path */
 	Candidate *src;
 	Candidate *targ;
@@ -1803,25 +1803,25 @@ FindDepsRegular(GNode *gn, CandidateSearcher *cs)
 
 	if (!(gn->type & OP_PHONY)) {
 
-		FindDepsRegularKnown(name, nameLen, gn, &srcs, &targs);
+		FindDepsRegularKnown(name, nameLen, gn, &sources, &targets);
 
 		/* Handle target of unknown suffix... */
-		FindDepsRegularUnknown(gn, name, &srcs, &targs);
+		FindDepsRegularUnknown(gn, name, &sources, &targets);
 
 		/*
 		 * Using the list of possible sources built up from the target
 		 * suffix(es), try and find an existing file/target that
 		 * matches.
 		 */
-		bottom = FindThem(&srcs, cs);
+		bottom = FindThem(&sources, cs);
 
 		if (bottom == NULL) {
 			/*
 			 * No known transformations -- use the first suffix
 			 * found for setting the local variables.
 			 */
-			if (targs.first != NULL)
-				targ = targs.first->datum;
+			if (targets.first != NULL)
+				targ = targets.first->datum;
 			else
 				targ = NULL;
 		} else {
@@ -1940,11 +1940,11 @@ sfnd_return:
 	if (bottom != NULL)
 		CandidateSearcher_AddIfNew(cs, bottom);
 
-	while (RemoveCandidate(&srcs) || RemoveCandidate(&targs))
+	while (RemoveCandidate(&sources) || RemoveCandidate(&targets))
 		continue;
 
-	CandidateSearcher_MoveAll(cs, &srcs);
-	CandidateSearcher_MoveAll(cs, &targs);
+	CandidateSearcher_MoveAll(cs, &sources);
+	CandidateSearcher_MoveAll(cs, &targets);
 }
 
 static void
diff --git a/targ.c b/targ.c
index 031cfb8b54d8..576d7dda8eed 100644
--- a/targ.c
+++ b/targ.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: targ.c,v 1.184 2024/07/07 09:54:12 rillig Exp $	*/
+/*	$NetBSD: targ.c,v 1.185 2025/05/07 19:49:00 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -107,7 +107,7 @@
 #include "dir.h"
 
 /*	"@(#)targ.c	8.2 (Berkeley) 3/19/94"	*/
-MAKE_RCSID("$NetBSD: targ.c,v 1.184 2024/07/07 09:54:12 rillig Exp $");
+MAKE_RCSID("$NetBSD: targ.c,v 1.185 2025/05/07 19:49:00 rillig Exp $");
 
 /*
  * All target nodes that appeared on the left-hand side of one of the
@@ -548,7 +548,8 @@ PrintOnlySources(void)
 void
 Targ_PrintGraph(int pass)
 {
-	debug_printf("#*** Input graph:\n");
+	debug_printf("#*** Begin input graph for pass %d in %s:\n",
+	    pass, curdir);
 	Targ_PrintNodes(&allTargets, pass);
 	debug_printf("\n");
 	debug_printf("\n");
@@ -568,6 +569,8 @@ Targ_PrintGraph(int pass)
 	debug_printf("\n");
 
 	Suff_PrintAll();
+	debug_printf("#*** End input graph for pass %d in %s:\n",
+	    pass, curdir);
 }
 
 /*
diff --git a/trace.c b/trace.c
index 9674cec7becb..a85053f62ce8 100644
--- a/trace.c
+++ b/trace.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: trace.c,v 1.33 2023/03/28 14:39:31 rillig Exp $	*/
+/*	$NetBSD: trace.c,v 1.35 2025/05/09 18:42:56 rillig Exp $	*/
 
 /*
  * Copyright (c) 2000 The NetBSD Foundation, Inc.
@@ -48,7 +48,7 @@
 #include "job.h"
 #include "trace.h"
 
-MAKE_RCSID("$NetBSD: trace.c,v 1.33 2023/03/28 14:39:31 rillig Exp $");
+MAKE_RCSID("$NetBSD: trace.c,v 1.35 2025/05/09 18:42:56 rillig Exp $");
 
 static FILE *trfile;
 static pid_t trpid;
@@ -102,11 +102,13 @@ Trace_Log(TrEvent event, Job *job)
 	    evname[event], trpid, trwd);
 #endif
 	if (job != NULL) {
+		GNode *gn = Job_Node(job);
+		char *type = GNodeType_ToString(gn->type);
 		char flags[4];
-
 		Job_FlagsToString(job, flags, sizeof flags);
-		fprintf(trfile, " %s %d %s %x", job->node->name,
-		    job->pid, flags, job->node->type);
+		fprintf(trfile, " %s %d %s %s",
+		    gn->name, Job_Pid(job), flags, type);
+		free(type);
 	}
 	fputc('\n', trfile);
 	fflush(trfile);
diff --git a/unit-tests/Makefile b/unit-tests/Makefile
index 7f1fe0a26c29..618a5959e304 100644
--- a/unit-tests/Makefile
+++ b/unit-tests/Makefile
@@ -1,6 +1,6 @@
-# $Id: Makefile,v 1.233 2025/04/14 16:02:33 sjg Exp $
+# $Id: Makefile,v 1.239 2025/06/15 21:32:16 sjg Exp $
 #
-# $NetBSD: Makefile,v 1.358 2025/04/13 09:29:32 rillig Exp $
+# $NetBSD: Makefile,v 1.367 2025/06/13 20:23:16 rillig Exp $
 #
 # Unit tests for make(1)
 #
@@ -222,6 +222,7 @@ TESTS+=		hanoi-include
 TESTS+=		impsrc
 TESTS+=		include-main
 TESTS+=		job-flags
+TESTS+=		job-output
 TESTS+=		job-output-long-lines
 TESTS+=		job-output-null
 TESTS+=		jobs-empty-commands
@@ -459,6 +460,7 @@ TESTS+=		varname-dot-suffixes
 TESTS+=		varname-dot-targets
 TESTS+=		varname-empty
 TESTS+=		varname-make
+TESTS+=		varname-make_stack_trace
 TESTS+=		varname-make_print_var_on_error
 TESTS+=		varname-make_print_var_on_error-jobs
 TESTS+=		varname-makefile
@@ -619,13 +621,7 @@ SED_CMDS.opt-debug-graph1=	${STD_SED_CMDS.dg1}
 SED_CMDS.opt-debug-graph2=	${STD_SED_CMDS.dg2}
 SED_CMDS.opt-debug-graph3=	${STD_SED_CMDS.dg3}
 SED_CMDS.opt-debug-hash=	-e 's,\(entries\)=[1-9][0-9],\1=<entries>,'
-SED_CMDS.opt-debug-jobs=	-e 's,([0-9][0-9]*),(<pid>),'
-SED_CMDS.opt-debug-jobs+=	-e 's,pid [0-9][0-9]*,pid <pid>,'
-SED_CMDS.opt-debug-jobs+=	-e 's,Process [0-9][0-9]*,Process <pid>,'
-SED_CMDS.opt-debug-jobs+=	-e 's,JobFinish: [0-9][0-9]*,JobFinish: <pid>,'
-SED_CMDS.opt-debug-jobs+=	-e 's,Command: ${.SHELL:T},Command: <shell>,'
-# The "-q" may be there or not, see jobs.c, variable shells.
-SED_CMDS.opt-debug-jobs+=	-e 's,^\(.Command: <shell>\) -q,\1,'
+SED_CMDS.opt-debug-jobs=	${STD_SED_CMDS.dj}
 SED_CMDS.opt-debug-lint+=	${STD_SED_CMDS.regex}
 SED_CMDS.opt-jobs-no-action=	${STD_SED_CMDS.hide-from-output}
 SED_CMDS.opt-no-action-runflags= ${STD_SED_CMDS.hide-from-output}
@@ -633,9 +629,12 @@ SED_CMDS.opt-where-am-i=	-e '/usr.obj/d'
 # For Compat_RunCommand, useShell == false.
 SED_CMDS.sh-dots=		-e 's,^.*\.\.\.:.*,<not found: ...>,'
 # For Compat_RunCommand, useShell == true.
-SED_CMDS.sh-dots+=		-e 's,^make: exec(\(.*\)) failed (.*)$$,<not found: \1>,'
+SED_CMDS.sh-dots+=		-e 's,^make: exec(\(.*\)): .*$$,<not found: \1>,'
 SED_CMDS.sh-dots+=		-e 's,^\(\*\*\* Error code \)[1-9][0-9]*,\1<nonzero>,'
+# Race condition between the child's stdout and make's status.
 SED_CMDS.sh-errctl=		${STD_SED_CMDS.dj}
+SED_CMDS.sh-errctl+=		-e '/^Process with pid/d'
+SED_CMDS.sh-errctl+=		-e '/^JobFinish:/d'
 SED_CMDS.sh-flags=		${STD_SED_CMDS.hide-from-output}
 SED_CMDS.shell-csh=		${STD_SED_CMDS.white-space}
 SED_CMDS.sh-leading-hyphen=	${STD_SED_CMDS.shell}
@@ -646,7 +645,7 @@ SED_CMDS.var-op-shell+=		${STD_SED_CMDS.shell}
 SED_CMDS.var-op-shell+=		-e '/command/s,No such.*,not found,'
 SED_CMDS.var-op-shell+=		${STD_SED_CMDS.white-space}
 SED_CMDS.vardebug+=		-e 's,${.SHELL},</path/to/shell>,'
-SED_CMDS.varmod-mtime+=		-e "s,\(.*\)': .*,\1': <ENOENT>,"
+SED_CMDS.varmod-mtime+=		-e "s,\(mtime for .*\): .*,\1: <ENOENT>,"
 SED_CMDS.varmod-subst-regex+=	${STD_SED_CMDS.regex}
 SED_CMDS.varparse-errors+=	${STD_SED_CMDS.timestamp}
 SED_CMDS.varname-dot-make-meta-ignore_filter+= ${SED_CMDS.meta-ignore}
@@ -662,7 +661,7 @@ SED_CMDS.varname-empty=		${.OBJDIR .PARSEDIR .PATH .SHELL .SYSPATH:L:@v@-e '/\\$
 # Some tests need an additional round of postprocessing.
 POSTPROC.depsrc-wait=		sed -e '/^---/d' -e 's,^\(: Making 3[abc]\)[123]$$,\1,'
 POSTPROC.deptgt-suffixes=	awk '/^\#\*\*\* Suffixes/,/^never-stop/'
-POSTPROC.gnode-submake=		awk '/Input graph/, /^$$/'
+POSTPROC.gnode-submake=		awk '/Begin input graph/, /^$$/'
 POSTPROC.varname-dot-make-mode=	sed 's,^\(: Making [abc]\)[123]$$,\1,'
 
 # Some tests reuse other tests, which makes them unnecessarily fragile.
@@ -698,12 +697,10 @@ STD_SED_CMDS.dg2+=	-e 's,\(last modified\) ..:..:.. ... ..\, ....,\1 <timestamp>
 STD_SED_CMDS.dg3=	${STD_SED_CMDS.dg2}
 
 # Omit details such as process IDs from the output of the -dj option.
-STD_SED_CMDS.dj= \
-	-e '/Process/d;/JobFinish:/d' \
-	-e 's,^\(Job_TokenWithdraw\)([0-9]*),\1(<pid>),' \
-	-e 's,^([0-9][0-9]*) \(withdrew token\),(<pid>) \1,' \
-	-e 's, \(pid\) [0-9][0-9]*, \1 <pid>,' \
-	-e 's,^\(	Command:\) .*,\1 <shell>,'
+STD_SED_CMDS.dj=	-e 's, pid [0-9][0-9]*, pid <pid>,'
+STD_SED_CMDS.dj+=	-e 's,^\(.Command\): ${.SHELL:T},\1: <shell>,'
+# The "-q" may be there or not, see jobs.c, variable shells.
+STD_SED_CMDS.dj+=	-e 's,^\(.Command: <shell>\) -q,\1,'
 
 # Reduce the noise for tests running with the -n option, since there is no
 # other way to suppress the echoing of the commands.
@@ -850,7 +847,7 @@ _SED_CMDS+=	-e 's,${.OBJDIR},<curdir>,g' -e 's,${.OBJDIR:tA},<curdir>,g'
 _SED_CMDS+=	-e 's,^${TEST_MAKE:T:S,.,\\.,g}[][0-9]*:,make:,'
 _SED_CMDS+=	-e 's,${TEST_MAKE:S,.,\\.,g},make,'
 _SED_CMDS+=	-e 's,^usage: ${TEST_MAKE:T:S,.,\\.,g} ,usage: make ,'
-_SED_CMDS+=	-e 's,${TEST_MAKE:T:S,.,\\.,g}\(\[[1-9][0-9]*\]:\),make\1,'
+_SED_CMDS+=	-e 's,${TEST_MAKE:T:S,.,\\.,g}\(\[[1-9][0-9]*\][: ]\),make\1,'
 _SED_CMDS+=	-e 's,<curdir>/,,g'
 _SED_CMDS+=	-e 's,${UNIT_TESTS:S,.,\\.,g}/,,g'
 _SED_CMDS+=	-e '/MAKE_VERSION/d'
diff --git a/unit-tests/archive.exp b/unit-tests/archive.exp
index 67b3d60ea9db..ea81a3589ff8 100644
--- a/unit-tests/archive.exp
+++ b/unit-tests/archive.exp
@@ -19,13 +19,13 @@ list-archive-wildcard: archive.mk
 list-archive-wildcard: ternary.mk
 
 make: archive.mk:61: Error in source archive spec "libprog.a${UNDEF}(archive.mk) pre post"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: Fatal errors encountered -- cannot continue
 make: stopped making "list-archive-undef-archive" in unit-tests
 exit 1
 
 make: archive.mk:68: Error in source archive spec "libprog.a"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: Fatal errors encountered -- cannot continue
 make: stopped making "list-archive-undef-member" in unit-tests
 exit 1
diff --git a/unit-tests/check-expect.lua b/unit-tests/check-expect.lua
new file mode 100644
index 000000000000..218056fbc021
--- /dev/null
+++ b/unit-tests/check-expect.lua
@@ -0,0 +1,190 @@
+#!  /usr/bin/lua
+-- $NetBSD: check-expect.lua,v 1.13 2025/04/13 09:29:32 rillig Exp $
+
+--[[
+
+usage: lua ./check-expect.lua *.mk
+
+Check that the various 'expect' comments in the .mk files produce the
+expected text in the corresponding .exp file.
+
+# expect: <line>
+        All of these lines must occur in the .exp file, in the same order as
+        in the .mk file.
+
+# expect-reset
+        Search the following 'expect:' comments from the top of the .exp
+        file again.
+
+# expect[+-]offset: <message>
+        Each message must occur in the .exp file and refer back to the
+        source line in the .mk file.
+
+# expect-not: <substring>
+        The substring must not occur as part of any line of the .exp file.
+
+# expect-not-matches: <pattern>
+        The pattern (see https://lua.org/manual/5.4/manual.html#6.4.1)
+        must not occur as part of any line of the .exp file.
+]]
+
+
+local had_errors = false
+---@param fmt string
+function print_error(fmt, ...)
+  print(fmt:format(...))
+  had_errors = true
+end
+
+
+---@return nil | string[]
+local function load_lines(fname)
+  local lines = {}
+
+  local f = io.open(fname, "r")
+  if f == nil then return nil end
+
+  for line in f:lines() do
+    table.insert(lines, line)
+  end
+  f:close()
+
+  return lines
+end
+
+
+---@param exp_lines string[]
+local function collect_lineno_diagnostics(exp_lines)
+  ---@type table<string, string[]>
+  local by_location = {}
+
+  for _, line in ipairs(exp_lines) do
+    ---@type string | nil, string, string
+    local l_fname, l_lineno, l_msg =
+      line:match('^make: ([^:]+):(%d+): (.*)')
+    if l_fname ~= nil then
+      local location = ("%s:%d"):format(l_fname, l_lineno)
+      if by_location[location] == nil then
+        by_location[location] = {}
+      end
+      table.insert(by_location[location], l_msg)
+    end
+  end
+
+  return by_location
+end
+
+
+local function missing(by_location)
+  ---@type {filename: string, lineno: number, location: string, message: string}[]
+  local missing_expectations = {}
+
+  for location, messages in pairs(by_location) do
+    for _, message in ipairs(messages) do
+      if message ~= "" and location:find(".mk:") then
+        local filename, lineno = location:match("^(%S+):(%d+)$")
+        table.insert(missing_expectations, {
+          filename = filename,
+          lineno = tonumber(lineno),
+          location = location,
+          message = message
+        })
+      end
+    end
+  end
+  table.sort(missing_expectations, function(a, b)
+    if a.filename ~= b.filename then
+      return a.filename < b.filename
+    end
+    return a.lineno < b.lineno
+  end)
+  return missing_expectations
+end
+
+
+local function check_mk(mk_fname)
+  local exp_fname = mk_fname:gsub("%.mk$", ".exp")
+  local mk_lines = load_lines(mk_fname)
+  local exp_lines = load_lines(exp_fname)
+  if exp_lines == nil then return end
+  local by_location = collect_lineno_diagnostics(exp_lines)
+  local prev_expect_line = 0
+
+  for mk_lineno, mk_line in ipairs(mk_lines) do
+
+    for text in mk_line:gmatch("#%s*expect%-not:%s*(.*)") do
+      local i = 1
+      while i <= #exp_lines and not exp_lines[i]:find(text, 1, true) do
+        i = i + 1
+      end
+      if i <= #exp_lines then
+        print_error("error: %s:%d: %s must not contain '%s'",
+          mk_fname, mk_lineno, exp_fname, text)
+      end
+    end
+
+    for text in mk_line:gmatch("#%s*expect%-not%-matches:%s*(.*)") do
+      local i = 1
+      while i <= #exp_lines and not exp_lines[i]:find(text) do
+        i = i + 1
+      end
+      if i <= #exp_lines then
+        print_error("error: %s:%d: %s must not match '%s'",
+          mk_fname, mk_lineno, exp_fname, text)
+      end
+    end
+
+    for text in mk_line:gmatch("#%s*expect:%s*(.*)") do
+      local i = prev_expect_line
+      -- As of 2022-04-15, some lines in the .exp files contain trailing
+      -- whitespace.  If possible, this should be avoided by rewriting the
+      -- debug logging.  When done, the trailing gsub can be removed.
+      -- See deptgt-phony.exp lines 14 and 15.
+      while i < #exp_lines and text ~= exp_lines[i + 1]:gsub("^%s*", ""):gsub("%s*$", "") do
+        i = i + 1
+      end
+      if i < #exp_lines then
+        prev_expect_line = i + 1
+      else
+        print_error("error: %s:%d: '%s:%d+' must contain '%s'",
+          mk_fname, mk_lineno, exp_fname, prev_expect_line + 1, text)
+      end
+    end
+    if mk_line:match("^#%s*expect%-reset$") then
+      prev_expect_line = 0
+    end
+
+    ---@param text string
+    for offset, text in mk_line:gmatch("#%s*expect([+%-]%d+):%s*(.*)") do
+      local location = ("%s:%d"):format(mk_fname, mk_lineno + tonumber(offset))
+
+      local found = false
+      if by_location[location] ~= nil then
+        for i, message in ipairs(by_location[location]) do
+          if message == text then
+            by_location[location][i] = ""
+            found = true
+            break
+          elseif message ~= "" then
+            print_error("error: %s:%d: out-of-order '%s'",
+              mk_fname, mk_lineno, message)
+          end
+        end
+      end
+
+      if not found then
+        print_error("error: %s:%d: %s must contain '%s'",
+          mk_fname, mk_lineno, exp_fname, text)
+      end
+    end
+  end
+
+  for _, m in ipairs(missing(by_location)) do
+    print_error("missing: %s: # expect+1: %s", m.location, m.message)
+  end
+end
+
+for _, fname in ipairs(arg) do
+  check_mk(fname)
+end
+os.exit(not had_errors)
diff --git a/unit-tests/cmd-errors-jobs.exp b/unit-tests/cmd-errors-jobs.exp
index a535f428e890..bd3ae1e51332 100644
--- a/unit-tests/cmd-errors-jobs.exp
+++ b/unit-tests/cmd-errors-jobs.exp
@@ -10,28 +10,34 @@ begin parse-error-direct
 make: Unclosed variable "UNCLOSED"
 	in command ": unexpected $@-${UNCLOSED"
 	in target "parse-error-unclosed-expression"
+	in make[1] in directory "<curdir>"
 make: Unclosed expression, expecting '}'
 	while evaluating variable "UNCLOSED" with value ""
 	in command ": unexpected $@-${UNCLOSED:"
 	in target "parse-error-unclosed-modifier"
+	in make[1] in directory "<curdir>"
 make: Unknown modifier ":Z"
 	while evaluating variable "UNKNOWN" with value ""
 	in command ": unexpected $@-${UNKNOWN:Z}-eol"
 	in target "parse-error-unknown-modifier"
+	in make[1] in directory "<curdir>"
 end parse-error-direct with status 2
 
 begin parse-error-indirect
 make: Unclosed variable "UNCLOSED"
 	in command ": unexpected $@-${UNCLOSED"
 	in target "parse-error-unclosed-expression"
+	in make[1] in directory "<curdir>"
 make: Unclosed expression, expecting '}'
 	while evaluating variable "UNCLOSED" with value ""
 	in command ": unexpected $@-${UNCLOSED:"
 	in target "parse-error-unclosed-modifier"
+	in make[1] in directory "<curdir>"
 make: Unknown modifier ":Z"
 	while evaluating variable "UNKNOWN" with value ""
 	in command ": unexpected $@-${UNKNOWN:Z}-eol"
 	in target "parse-error-unknown-modifier"
+	in make[1] in directory "<curdir>"
 end parse-error-indirect with status 2
 
 begin begin-direct
diff --git a/unit-tests/cond-func-empty.exp b/unit-tests/cond-func-empty.exp
index fce2bc443f6b..7861edc74ba2 100644
--- a/unit-tests/cond-func-empty.exp
+++ b/unit-tests/cond-func-empty.exp
@@ -1,4 +1,5 @@
-make: cond-func-empty.mk:167: Unclosed variable "WORD"
+make: cond-func-empty.mk:156: warning: Invalid character " " in variable name " WORD "
+make: cond-func-empty.mk:168: Unclosed variable "WORD"
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/cond-func-empty.mk b/unit-tests/cond-func-empty.mk
index 17e76a63f2e8..ab097b026dcb 100644
--- a/unit-tests/cond-func-empty.mk
+++ b/unit-tests/cond-func-empty.mk
@@ -1,4 +1,4 @@
-# $NetBSD: cond-func-empty.mk,v 1.28 2025/01/11 20:54:45 rillig Exp $
+# $NetBSD: cond-func-empty.mk,v 1.29 2025/06/11 18:49:58 sjg Exp $
 #
 # Tests for the empty() function in .if conditions, which tests an
 # expression for emptiness.
@@ -152,6 +152,7 @@ ${:U }=	space
 
 # There may be spaces outside the parentheses.
 # Spaces inside the parentheses are interpreted as part of the variable name.
+# expect+1: warning: Invalid character " " in variable name " WORD "
 .if ! empty ( WORD )
 .  error
 .endif
diff --git a/unit-tests/cond-late.exp b/unit-tests/cond-late.exp
index 6cd20d797d3e..13846e8c822a 100644
--- a/unit-tests/cond-late.exp
+++ b/unit-tests/cond-late.exp
@@ -1,7 +1,7 @@
 make: cond-late.mk:38: Bad condition
 	while evaluating condition " != "no""
 	while evaluating variable "VAR" with value "${${UNDEF} != "no":?:}"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: Fatal errors encountered -- cannot continue
 make: stopped making "do-parse-time" in unit-tests
 yes
diff --git a/unit-tests/dep-op-missing.exp b/unit-tests/dep-op-missing.exp
index 5ae39b5fd256..8521dbf79792 100644
--- a/unit-tests/dep-op-missing.exp
+++ b/unit-tests/dep-op-missing.exp
@@ -1,5 +1,5 @@
 make: dep-op-missing.tmp:1: Invalid line 'target'
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 0
diff --git a/unit-tests/deptgt-suffixes.exp b/unit-tests/deptgt-suffixes.exp
index 512e6d44a8be..9ab59fcd4810 100644
--- a/unit-tests/deptgt-suffixes.exp
+++ b/unit-tests/deptgt-suffixes.exp
@@ -26,6 +26,7 @@
 .src-right.tgt-left:
 	: Making ${.TARGET} from ${.IMPSRC}.
 
+#*** End input graph for pass 1 in <curdir>:
 : Making deptgt-suffixes.src-left out of nothing.
 : Making deptgt-suffixes.tgt-right from deptgt-suffixes.src-left.
 : Making deptgt-suffixes.src-right out of nothing.
diff --git a/unit-tests/directive-for-errors.exp b/unit-tests/directive-for-errors.exp
index 6064f35a1944..39929864314d 100644
--- a/unit-tests/directive-for-errors.exp
+++ b/unit-tests/directive-for-errors.exp
@@ -8,7 +8,7 @@ make: directive-for-errors.mk:44: invalid character '$' in .for loop variable na
 make: directive-for-errors.mk:52: no iteration variables in for
 make: directive-for-errors.mk:64: Wrong number of words (5) in .for substitution list with 3 variables
 make: directive-for-errors.mk:78: missing `in' in for
-make: directive-for-errors.mk:86: Unknown modifier ":Z"
+make: directive-for-errors.mk:85: Unknown modifier ":Z"
 	while evaluating "${:U3:Z} 4" with value "3"
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
diff --git a/unit-tests/directive-for-errors.mk b/unit-tests/directive-for-errors.mk
index 42f93b0212f2..a58b8294289b 100644
--- a/unit-tests/directive-for-errors.mk
+++ b/unit-tests/directive-for-errors.mk
@@ -1,4 +1,4 @@
-# $NetBSD: directive-for-errors.mk,v 1.16 2025/03/30 16:43:10 rillig Exp $
+# $NetBSD: directive-for-errors.mk,v 1.17 2025/05/03 08:18:33 rillig Exp $
 #
 # Tests for error handling in .for loops.
 
@@ -73,11 +73,10 @@ ${:U\\}=	backslash	# see whether the "variable" '\' is local
 .endfor
 
 
-# A missing 'in' should parse the .for loop but skip the body.
+# A missing 'in' parses the .for loop but skips the body.
 # expect+1: missing `in' in for
 .for i over k
-# XXX: As of 2020-12-31, this line is reached once.
-.  warning Should not be reached.
+.  error
 .endfor
 
 
diff --git a/unit-tests/directive-for-null.exp b/unit-tests/directive-for-null.exp
index 0a94c7d9e451..60caebee238f 100644
--- a/unit-tests/directive-for-null.exp
+++ b/unit-tests/directive-for-null.exp
@@ -1,5 +1,5 @@
 make: (stdin):2: Zero byte read from file
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 *** Error code 2 (continuing)
 
 Stop.
diff --git a/unit-tests/gnode-submake.exp b/unit-tests/gnode-submake.exp
index ea00e8d76c11..c9cfada91c69 100644
--- a/unit-tests/gnode-submake.exp
+++ b/unit-tests/gnode-submake.exp
@@ -1,4 +1,4 @@
-#*** Input graph:
+#*** Begin input graph for pass 1 in <curdir>:
 # all, unmade, type OP_DEPENDS, flags none
 # makeinfo, unmade, type OP_DEPENDS|OP_HAS_COMMANDS, flags none
 # make-index, unmade, type OP_DEPENDS|OP_SUBMAKE|OP_HAS_COMMANDS, flags none
diff --git a/unit-tests/job-output.exp b/unit-tests/job-output.exp
new file mode 100644
index 000000000000..1891021bf3e7
--- /dev/null
+++ b/unit-tests/job-output.exp
@@ -0,0 +1,13 @@
+begin empty-lines
+
+
+end empty-lines
+begin stdout-and-stderr
+only stdout:
+This is stdout.
+This is stderr.
+only stderr:
+end stdout-and-stderr
+This is stdout.
+This is stderr.
+exit status 0
diff --git a/unit-tests/job-output.mk b/unit-tests/job-output.mk
new file mode 100644
index 000000000000..ae4708a5b2f8
--- /dev/null
+++ b/unit-tests/job-output.mk
@@ -0,0 +1,41 @@
+# $NetBSD: job-output.mk,v 1.2 2025/06/13 06:13:20 rillig Exp $
+#
+# Tests for handling the output in parallel mode.
+
+all: .PHONY
+	@${MAKE} -f ${MAKEFILE} -j1 empty-lines
+	@${MAKE} -f ${MAKEFILE} -j1 stdout-and-stderr
+	@${MAKE} -f ${MAKEFILE} -j1 echo-on-stdout-and-stderr
+
+# By sleeping for a second, the output of the child process is written byte
+# by byte, to be consumed in small pieces by make.  No matter what the chunk
+# size is, the empty lines must not be discarded.
+empty-lines: .PHONY
+	@echo begin $@
+	@sleep 1
+	@echo
+	@sleep 1
+	@echo
+	@sleep 1
+	@echo end $@
+
+# In parallel mode, both stdout and stderr from the child process are
+# collected in a local buffer and then written to make's stdout.
+#
+# expect: begin stdout-and-stderr
+# expect: only stdout:
+# expect: This is stdout.
+# expect: This is stderr.
+# expect: only stderr:
+# expect: end stdout-and-stderr
+stdout-and-stderr:
+	@echo begin $@
+	@echo only stdout:
+	@${MAKE} -f ${MAKEFILE} echo-on-stdout-and-stderr 2>/dev/null
+	@echo only stderr:
+	@${MAKE} -f ${MAKEFILE} echo-on-stdout-and-stderr 1>/dev/null
+	@echo end $@
+
+echo-on-stdout-and-stderr: .PHONY
+	@echo This is stdout.
+	@echo This is stderr. 1>&2
diff --git a/unit-tests/objdir-writable.exp b/unit-tests/objdir-writable.exp
index dc5cd706349e..3fbf82c0522a 100644
--- a/unit-tests/objdir-writable.exp
+++ b/unit-tests/objdir-writable.exp
@@ -1,4 +1,4 @@
-make: warning: <tmpdir>/roobj: Permission denied.
+make: warning: <tmpdir>/roobj: Permission denied
 <tmpdir>
 <tmpdir>/roobj
 <tmpdir>/roobj
diff --git a/unit-tests/opt-debug-graph1.exp b/unit-tests/opt-debug-graph1.exp
index d01a98a31fdb..9dae95302318 100644
--- a/unit-tests/opt-debug-graph1.exp
+++ b/unit-tests/opt-debug-graph1.exp
@@ -1,4 +1,4 @@
-#*** Input graph:
+#*** Begin input graph for pass 1 in <curdir>:
 # all, unmade, type OP_DEPENDS|OP_HAS_COMMANDS, flags none
 # made-target, unmade, type OP_DEPENDS, flags none
 # made-target-no-sources, unmade, type OP_DEPENDS, flags none
@@ -50,4 +50,5 @@ MFLAGS           =   -r -k -d g1
 
 #*** Suffixes:
 #*** Transformations:
+#*** End input graph for pass 1 in <curdir>:
 exit status 0
diff --git a/unit-tests/opt-debug-graph2.exp b/unit-tests/opt-debug-graph2.exp
index b590e7379ddb..e4160e413787 100644
--- a/unit-tests/opt-debug-graph2.exp
+++ b/unit-tests/opt-debug-graph2.exp
@@ -4,7 +4,7 @@ false
 false
 *** Error code 1 (continuing)
 `all' not remade because of errors.
-#*** Input graph:
+#*** Begin input graph for pass 2 in <curdir>:
 # made-target, made, type OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND|OP_MARK, flags REMAKE|DONE_ALLSRC
 #
 # *** MAIN TARGET ***
@@ -85,6 +85,7 @@ MFLAGS           =   -r -k -d g2
 
 #*** Suffixes:
 #*** Transformations:
+#*** End input graph for pass 2 in <curdir>:
 
 Stop.
 make: stopped making "all" in unit-tests
diff --git a/unit-tests/opt-debug-graph3.exp b/unit-tests/opt-debug-graph3.exp
index d1be69f89630..ccebfd7b16bc 100644
--- a/unit-tests/opt-debug-graph3.exp
+++ b/unit-tests/opt-debug-graph3.exp
@@ -4,7 +4,7 @@ false
 false
 *** Error code 1 (continuing)
 `all' not remade because of errors.
-#*** Input graph:
+#*** Begin input graph for pass 3 in <curdir>:
 # made-target, made, type OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND|OP_MARK, flags REMAKE|DONE_ALLSRC
 #
 # *** MAIN TARGET ***
@@ -85,6 +85,7 @@ MFLAGS           =   -r -k -d g3
 
 #*** Suffixes:
 #*** Transformations:
+#*** End input graph for pass 3 in <curdir>:
 
 Stop.
 make: stopped making "all" in unit-tests
diff --git a/unit-tests/opt-debug-jobs.exp b/unit-tests/opt-debug-jobs.exp
index e79d8e94a952..6cda45107702 100644
--- a/unit-tests/opt-debug-jobs.exp
+++ b/unit-tests/opt-debug-jobs.exp
@@ -1,6 +1,6 @@
 job_pipe -1 -1, maxjobs 1, tokens 1, compat 0
-Job_TokenWithdraw(<pid>): aborting 0, running 0
-(<pid>) withdrew token
+TokenPool_Take: pid <pid>, aborting NONE, running 0
+TokenPool_Take: pid <pid> took a token
 echo ": expanded expression"
 { : expanded expression 
 } || exit $?
@@ -13,15 +13,15 @@ echo ": 'single' and \"double\" quotes"
 { sleep 1 
 } || exit $?
 Running all
-	Command: <shell> 
-JobExec(all): pid <pid> added to jobs table
-job table @ job started
-job 0, status 3, flags ---, pid <pid>
+	Command: <shell>
+JobExec: target all, pid <pid> added to jobs table
+job started, job table:
+job 0, status running, flags ---, pid <pid>
 : expanded expression
 :  variable
 : 'single' and "double" quotes
-Process <pid> exited/stopped status 0.
-JobFinish: <pid> [all], status 0
-Job_TokenWithdraw(<pid>): aborting 0, running 0
-(<pid>) withdrew token
+Process with pid <pid> exited/stopped with status 0.
+JobFinish: target all, pid <pid>, status 0
+TokenPool_Take: pid <pid>, aborting NONE, running 0
+TokenPool_Take: pid <pid> took a token
 exit status 0
diff --git a/unit-tests/opt-file.exp b/unit-tests/opt-file.exp
index 3087ab790d2e..d915f9fe0170 100644
--- a/unit-tests/opt-file.exp
+++ b/unit-tests/opt-file.exp
@@ -2,7 +2,7 @@ value
 value
 line-with-trailing-whitespace
 make: (stdin):1: Zero byte read from file
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 *** Error code 2 (continuing)
 `all' not remade because of errors.
 
diff --git a/unit-tests/opt-jobs-internal.exp b/unit-tests/opt-jobs-internal.exp
index 470bdbddd0f8..e3e8ee498224 100644
--- a/unit-tests/opt-jobs-internal.exp
+++ b/unit-tests/opt-jobs-internal.exp
@@ -1,6 +1,27 @@
-make: internal error -- J option malformed (garbage)
-usage: make [-BeikNnqrSstWwX]
-            [-C directory] [-D variable] [-d flags] [-f makefile]
-            [-I directory] [-J private] [-j max_jobs] [-m directory] [-T file]
-            [-V variable] [-v variable] [variable=value] [target ...]
-exit status 2
+direct: mode=parallel
+make: error: invalid internal option "-J garbage" in "<curdir>"
+make: warning: internal option "-J" in "<curdir>" refers to unopened file descriptors; falling back to compat mode.
+	To run the target even in -n mode, add the .MAKE pseudo-source to the target.
+	To run the target in default mode only, add a ${:D make} marker to a target's command. (This marker expression expands to an empty string.)
+	To make the sub-make run in compat mode, add -B to its invocation.
+	To make the sub-make independent from the parent make, unset the MAKEFLAGS environment variable in the target's commands.
+	in make[2] in directory "<curdir>"
+direct-open: mode=compat
+make: warning: internal option "-J" in "<curdir>" refers to unopened file descriptors; falling back to compat mode.
+	To run the target even in -n mode, add the .MAKE pseudo-source to the target.
+	To run the target in default mode only, add a ${:D make} marker to a target's command. (This marker expression expands to an empty string.)
+	To make the sub-make run in compat mode, add -B to its invocation.
+	To make the sub-make independent from the parent make, unset the MAKEFLAGS environment variable in the target's commands.
+	in make[2] in directory "<curdir>"
+indirect-open: mode=compat
+indirect-expr: mode=parallel
+make: warning: internal option "-J" in "<curdir>" refers to unopened file descriptors; falling back to compat mode.
+	To run the target even in -n mode, add the .MAKE pseudo-source to the target.
+	To run the target in default mode only, add a ${:D make} marker to a target's command. (This marker expression expands to an empty string.)
+	To make the sub-make run in compat mode, add -B to its invocation.
+	To make the sub-make independent from the parent make, unset the MAKEFLAGS environment variable in the target's commands.
+	in make[2] in directory "<curdir>"
+indirect-comment: mode=compat
+indirect-silent-comment: mode=parallel
+indirect-expr-empty: mode=parallel
+exit status 0
diff --git a/unit-tests/opt-jobs-internal.mk b/unit-tests/opt-jobs-internal.mk
index 44755a797751..13db820f86c1 100644
--- a/unit-tests/opt-jobs-internal.mk
+++ b/unit-tests/opt-jobs-internal.mk
@@ -1,9 +1,65 @@
-# $NetBSD: opt-jobs-internal.mk,v 1.3 2022/01/23 16:09:38 rillig Exp $
+# $NetBSD: opt-jobs-internal.mk,v 1.6 2025/05/23 21:05:56 rillig Exp $
 #
-# Tests for the (intentionally undocumented) -J command line option.
-#
-# Only test the error handling here, the happy path is covered in other tests
-# as a side effect.
+# Tests for the (intentionally undocumented) internal -J command line option.
+
+# This test expects
+.MAKE.ALWAYS_PASS_JOB_QUEUE= no
+
+all: .PHONY
+	@${MAKE} -f ${MAKEFILE} -j1 direct
+	@${MAKE} -f ${MAKEFILE} -j1 direct-syntax
+	@${MAKE} -f ${MAKEFILE} -j1 direct-open
+	@${MAKE} -f ${MAKEFILE} -j1 indirect-open
+	@${MAKE} -f ${MAKEFILE} -j1 indirect-expr
+	@${MAKE} -f ${MAKEFILE} -j1 indirect-comment
+	@${MAKE} -f ${MAKEFILE} -j1 indirect-silent-comment
+	@${MAKE} -f ${MAKEFILE} -j1 indirect-expr-empty
+
+detect-mode: .PHONY
+	@mode=parallel
+	@echo ${HEADING}: mode=$${mode:-compat}
+
+# expect: direct: mode=parallel
+direct: .PHONY
+	@mode=parallel
+	@echo ${.TARGET}: mode=$${mode:-compat}
+
+# expect: make: error: invalid internal option "-J garbage" in "<curdir>"
+direct-syntax: .PHONY
+	@${MAKE} -f ${MAKEFILE} -J garbage unexpected-target || :
+
+# expect: direct-open: mode=compat
+direct-open: .PHONY
+	@${MAKE} -f ${MAKEFILE} -J 31,32 detect-mode HEADING=${.TARGET}
+
+# expect: indirect-open: mode=compat
+indirect-open: .PHONY
+	@${MAKE:U} -f ${MAKEFILE} detect-mode HEADING=${.TARGET}
+
+# When a command in its unexpanded form contains the expression "${MAKE}"
+# without any modifiers, the file descriptors get passed around.
+# expect: indirect-expr: mode=parallel
+indirect-expr: .PHONY
+	@${MAKE} -f ${MAKEFILE} detect-mode HEADING=${.TARGET}
+
+# The "# make" comment starts directly after the leading tab and is thus not
+# considered a shell command line. No file descriptors are passed around.
+# expect: indirect-comment: mode=compat
+indirect-comment: .PHONY
+	# make
+	@${MAKE:U} -f ${MAKEFILE} detect-mode HEADING=${.TARGET}
+
+# When the "# make" comment is prefixed with "@", it becomes a shell command.
+# As that shell command contains the plain word "make", the file descriptors
+# get passed around.
+# expect: indirect-silent-comment: mode=parallel
+indirect-silent-comment: .PHONY
+	@# make
+	@${MAKE:U} -f ${MAKEFILE} detect-mode HEADING=${.TARGET}
 
-# expect: make: internal error -- J option malformed (garbage)
-.MAKEFLAGS: -Jgarbage
+# When a command in its unexpanded form contains the plain word "make", the
+# file descriptors get passed around.
+# expect: indirect-expr-empty: mode=parallel
+indirect-expr-empty: .PHONY
+	@${:D make}
+	@${MAKE:U} -f ${MAKEFILE} detect-mode HEADING=${.TARGET}
diff --git a/unit-tests/opt-jobs.mk b/unit-tests/opt-jobs.mk
index ce84e47e91e1..818a4844e94b 100644
--- a/unit-tests/opt-jobs.mk
+++ b/unit-tests/opt-jobs.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-jobs.mk,v 1.5 2023/09/10 16:25:32 sjg Exp $
+# $NetBSD: opt-jobs.mk,v 1.7 2025/05/20 17:56:40 sjg Exp $
 #
 # Tests for the -j command line option, which creates the targets in parallel.
 
diff --git a/unit-tests/opt-touch-jobs.mk b/unit-tests/opt-touch-jobs.mk
index 6005ab49d125..8c9c25c59015 100644
--- a/unit-tests/opt-touch-jobs.mk
+++ b/unit-tests/opt-touch-jobs.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-touch-jobs.mk,v 1.2 2021/01/30 12:14:08 rillig Exp $
+# $NetBSD: opt-touch-jobs.mk,v 1.3 2025/05/18 06:24:27 rillig Exp $
 #
 # Tests for the -t command line option in jobs mode.
 
@@ -27,7 +27,7 @@ opt-touch-use: .USE
 # Even though it is listed last, in the output it appears first.
 # This is because it is the only node that actually needs to be run.
 # The "is up to date" of the other nodes happens after all jobs have
-# finished, by Make_Run > MakePrintStatusList > MakePrintStatus.
+# finished, by Make_MakeParallel > MakePrintStatusList > MakePrintStatus.
 opt-touch-make: .MAKE
 	: Making $@.
 
diff --git a/unit-tests/opt-tracefile.exp b/unit-tests/opt-tracefile.exp
index 0e815606d34f..202c3c1afe49 100644
--- a/unit-tests/opt-tracefile.exp
+++ b/unit-tests/opt-tracefile.exp
@@ -1,12 +1,12 @@
 Making dependency1 from <nothing>.
 Making dependency2 from <nothing>.
 Making trace from dependency1 dependency2.
-0 BEG
-1 JOB
-1 DON
-1 JOB
-1 DON
-1 JOB
-1 DON
-0 END
+<timestamp> 0 BEG <make-pid> <curdir>
+<timestamp> 1 JOB <make-pid> <curdir> dependency1 <job-pid> --- OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND|OP_MARK
+<timestamp> 1 DON <make-pid> <curdir> dependency1 <job-pid> --- OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND|OP_MARK
+<timestamp> 1 JOB <make-pid> <curdir> dependency2 <job-pid> --- OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND|OP_MARK
+<timestamp> 1 DON <make-pid> <curdir> dependency2 <job-pid> --- OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND|OP_MARK
+<timestamp> 1 JOB <make-pid> <curdir> trace <job-pid> --- OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND
+<timestamp> 1 DON <make-pid> <curdir> trace <job-pid> --- OP_DEPENDS|OP_PHONY|OP_HAS_COMMANDS|OP_DEPS_FOUND
+<timestamp> 0 END <make-pid> <curdir>
 exit status 0
diff --git a/unit-tests/opt-tracefile.mk b/unit-tests/opt-tracefile.mk
index 291824680606..d94c8045c224 100644
--- a/unit-tests/opt-tracefile.mk
+++ b/unit-tests/opt-tracefile.mk
@@ -1,4 +1,4 @@
-# $NetBSD: opt-tracefile.mk,v 1.5 2021/12/06 22:35:20 rillig Exp $
+# $NetBSD: opt-tracefile.mk,v 1.6 2025/05/09 18:38:40 rillig Exp $
 #
 # Tests for the command line option '-T', which in jobs mode appends a trace
 # record to a trace log whenever a job is started or completed.
@@ -6,8 +6,7 @@
 all: .PHONY
 	@rm -f opt-tracefile.log
 	@${MAKE} -f ${MAKEFILE} -j1 -Topt-tracefile.log trace
-	# Remove timestamps, process IDs and directory paths.
-	@awk '{ print $$2, $$3 }' opt-tracefile.log
+	@awk '{ $$1 = "<timestamp>"; $$4 = "<make-pid>"; if (NF >= 7) $$7 = "<job-pid>"; print }' opt-tracefile.log
 	@rm opt-tracefile.log
 
 trace dependency1 dependency2: .PHONY
diff --git a/unit-tests/sh-errctl.exp b/unit-tests/sh-errctl.exp
index 8e6bc3c82125..8419d215fe38 100644
--- a/unit-tests/sh-errctl.exp
+++ b/unit-tests/sh-errctl.exp
@@ -1,6 +1,6 @@
 job_pipe -1 -1, maxjobs 1, tokens 1, compat 0
-Job_TokenWithdraw(<pid>): aborting 0, running 0
-(<pid>) withdrew token
+TokenPool_Take: pid <pid>, aborting NONE, running 0
+TokenPool_Take: pid <pid> took a token
 # echo off
 echo silent
 # echo on
@@ -16,12 +16,12 @@ set -e
 echo always
 Running all
 	Command: <shell>
-JobExec(all): pid <pid> added to jobs table
-job table @ job started
-job 0, status 3, flags ---, pid <pid>
+JobExec: target all, pid <pid> added to jobs table
+job started, job table:
+job 0, status running, flags ---, pid <pid>
 silent
 ignerr
 always
-Job_TokenWithdraw(<pid>): aborting 0, running 0
-(<pid>) withdrew token
+TokenPool_Take: pid <pid>, aborting NONE, running 0
+TokenPool_Take: pid <pid> took a token
 exit status 0
diff --git a/unit-tests/shell-csh.mk b/unit-tests/shell-csh.mk
index 21517d5dbd78..cfe28199dbd2 100644
--- a/unit-tests/shell-csh.mk
+++ b/unit-tests/shell-csh.mk
@@ -1,4 +1,4 @@
-# $NetBSD: shell-csh.mk,v 1.9 2024/05/25 15:37:17 rillig Exp $
+# $NetBSD: shell-csh.mk,v 1.10 2025/06/05 21:56:54 rillig Exp $
 #
 # Tests for using a C shell for running the commands.
 
@@ -33,7 +33,9 @@ all:
 	-echo ignore errors
 
 	# In the C shell, "unset verbose" is set as the noPrint command.
-	# Therefore it is filtered from the output, rather naively.
+	# Therefore, it is filtered from the output, rather naively.
+# FIXME: Don't assume a newline character in PrintFilteredOutput.
+# expect: They chatted in the sy.
 	@echo 'They chatted in the sunset verbosely.'
 .else
 	@sed '$$d' ${MAKEFILE:.mk=.exp}	# This is cheated.
diff --git a/unit-tests/shell-ksh.exp b/unit-tests/shell-ksh.exp
index 0bf83203a23a..fcb9fb888d21 100644
--- a/unit-tests/shell-ksh.exp
+++ b/unit-tests/shell-ksh.exp
@@ -1,4 +1,9 @@
-: normal
-: always
-: ignore errors
+echo normal
+normal
+hidden
+echo always
+always
+echo ignore errors
+ignore errors
+The "is filtered out.
 exit status 0
diff --git a/unit-tests/shell-ksh.mk b/unit-tests/shell-ksh.mk
index 3acf98cdb5d1..676c8e2d47d9 100644
--- a/unit-tests/shell-ksh.mk
+++ b/unit-tests/shell-ksh.mk
@@ -1,11 +1,39 @@
-# $NetBSD: shell-ksh.mk,v 1.1 2020/10/03 14:39:36 rillig Exp $
+# $NetBSD: shell-ksh.mk,v 1.2 2025/06/05 21:56:54 rillig Exp $
 #
-# Tests for using a korn shell for running the commands.
+# Tests for using a Korn shell for running the commands.
 
-.SHELL: name="ksh" path="ksh"
+KSH!=	which ksh 2> /dev/null || true
+
+# The shell path must be an absolute path.
+# This is only obvious in parallel mode since in compat mode,
+# simple commands are executed via execvp directly.
+.if ${KSH} != ""
+.SHELL: name="ksh" path="${KSH}"
+.endif
+
+# In parallel mode, the shell->noPrint command is filtered from
+# the output, rather naively (in PrintOutput).
+.MAKEFLAGS: -j1
 
 all:
-	: normal
-	@: hidden
-	+: always
-	-: ignore errors
+.if ${KSH} != ""
+	# This command is both printed and executed.
+	echo normal
+
+	# This command is only executed.
+	@echo hidden
+
+	# This command is both printed and executed.
+	+echo always
+
+	# This command is both printed and executed.
+	-echo ignore errors
+
+	# In the Korn shell, "set +v" is set as the noPrint command.
+	# Therefore, it is filtered from the output, rather naively.
+# FIXME: Don't assume a newline character in PrintFilteredOutput.
+# expect: The "is filtered out.
+	@echo 'The "set +v" is filtered out.'
+.else
+	@sed '$$d' ${MAKEFILE:.mk=.exp}	# This is cheated.
+.endif
diff --git a/unit-tests/suff-main-several.exp b/unit-tests/suff-main-several.exp
index c06fb0cf88b9..bb1fc91ea21d 100644
--- a/unit-tests/suff-main-several.exp
+++ b/unit-tests/suff-main-several.exp
@@ -63,7 +63,7 @@ Target "next-main" depends on "suff-main-several.{2,3,4}"
 # suff-main-several.{2,3,4}, unmade, type none, flags none
 Parsing suff-main-several.mk:42: .MAKEFLAGS: -d0 -dg1
 ParseDependency(.MAKEFLAGS: -d0 -dg1)
-#*** Input graph:
+#*** Begin input graph for pass 1 in <curdir>:
 # .1.2, unmade, type OP_TRANSFORM, flags none
 # .1.3, unmade, type OP_TRANSFORM, flags none
 # .1.4, unmade, type OP_TRANSFORM, flags none
@@ -131,6 +131,7 @@ MFLAGS           =   -r -k -d mps -d 0 -d g1
 #	From: 
 #	Search Path: 
 #*** Transformations:
+#*** End input graph for pass 1 in <curdir>:
 make: don't know how to make suff-main-several.2 (continuing)
 make: don't know how to make suff-main-several.3 (continuing)
 make: don't know how to make suff-main-several.4 (continuing)
diff --git a/unit-tests/suff-transform-debug.exp b/unit-tests/suff-transform-debug.exp
index 2e88db58bc8c..ad0584f204d1 100644
--- a/unit-tests/suff-transform-debug.exp
+++ b/unit-tests/suff-transform-debug.exp
@@ -1,4 +1,4 @@
-#*** Input graph:
+#*** Begin input graph for pass 1 in <curdir>:
 # all, unmade, type OP_DEPENDS, flags none
 
 
@@ -59,4 +59,5 @@ MFLAGS           =   -r -k -d g1
 .cpp.a          :
 	: Making ${.TARGET} from impsrc ${.IMPSRC} allsrc ${.ALLSRC}.
 
+#*** End input graph for pass 1 in <curdir>:
 exit status 0
diff --git a/unit-tests/var-op-expand.exp b/unit-tests/var-op-expand.exp
index 88d2333a3f6f..105d2f50acc8 100644
--- a/unit-tests/var-op-expand.exp
+++ b/unit-tests/var-op-expand.exp
@@ -6,6 +6,18 @@ make: var-op-expand.mk:283: Unknown modifier ":s,value,replaced,"
 	while evaluating variable "later" with value "lowercase-value"
 	while evaluating variable "indirect" with value "${later:s,value,replaced,} ok ${later:value=sysv}"
 make: var-op-expand.mk:285: warning: XXX Neither branch should be taken.
+make: var-op-expand.mk:297: Bad condition
+	while evaluating condition " < 0 "
+make: var-op-expand.mk:297: Unknown modifier ":Z1"
+	while parsing "${:Z1}:${:Z2}}"
+	while evaluating then-branch of condition " < 0 "
+make: var-op-expand.mk:297: Unknown modifier ":Z2"
+	while parsing "${:Z2}}"
+	while evaluating else-branch of condition " < 0 "
+make: var-op-expand.mk:297: Unknown modifier ":Z1"
+	while evaluating "${:Z1}:${:Z2}}" with value ""
+make: var-op-expand.mk:297: Unknown modifier ":Z2"
+	while evaluating "${:Z2}}" with value ""
 make: Fatal errors encountered -- cannot continue
-make: stopped making "all" in unit-tests
+make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/var-op-expand.mk b/unit-tests/var-op-expand.mk
index 863ed19d4348..6a49648f0618 100644
--- a/unit-tests/var-op-expand.mk
+++ b/unit-tests/var-op-expand.mk
@@ -1,4 +1,4 @@
-# $NetBSD: var-op-expand.mk,v 1.23 2025/03/29 19:08:52 rillig Exp $
+# $NetBSD: var-op-expand.mk,v 1.24 2025/04/30 06:01:07 rillig Exp $
 #
 # Tests for the := variable assignment operator, which expands its
 # right-hand side.
@@ -288,5 +288,10 @@ later=	lowercase-value
 .endif
 
 
-all:
-	@:;
+# FIXME: The expression is evaluated twice, for no obvious reason.
+# expect+5: Bad condition
+# expect+4: Unknown modifier ":Z1"
+# expect+3: Unknown modifier ":Z2"
+# expect+2: Unknown modifier ":Z1"
+# expect+1: Unknown modifier ":Z2"
+_:=	${ < 0 :?${:Z1}:${:Z2}}
diff --git a/unit-tests/var-recursive.exp b/unit-tests/var-recursive.exp
index 75701e4c8c4f..97568873bf1b 100644
--- a/unit-tests/var-recursive.exp
+++ b/unit-tests/var-recursive.exp
@@ -1,20 +1,20 @@
 make: var-recursive.mk:11: Variable DIRECT is recursive.
 	while evaluating variable "DIRECT" with value "${DIRECT}"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: var-recursive.mk:11: <>
 make: var-recursive.mk:19: Variable INDIRECT1 is recursive.
 	while evaluating variable "INDIRECT2" with value "${INDIRECT1}"
 	while evaluating variable "INDIRECT1" with value "${INDIRECT2}"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: var-recursive.mk:19: <>
 make: var-recursive.mk:26: <ok>
 make: var-recursive.mk:34: Variable MODIFIERS is recursive.
 	while evaluating variable "MODIFIERS" with value "${MODIFIERS:Mpattern}"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: var-recursive.mk:34: <Mpattern}>
 make: var-recursive.mk:43: Variable V is recursive.
 	while evaluating variable "V" with value "$V"
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: var-recursive.mk:43: <>
 make: Fatal errors encountered -- cannot continue
 make: stopped making "loadtime" in unit-tests
@@ -24,5 +24,6 @@ make: Variable VAR is recursive.
 	while evaluating variable "VAR" with value "${VAR}"
 	in command ": recursive-line-before <${VAR}> recursive-line-after"
 	in target "runtime"
+	in make[1] in directory "<curdir>"
 sub-exit status 2
 exit status 0
diff --git a/unit-tests/varmod-assign.exp b/unit-tests/varmod-assign.exp
index a4b689ab9fd4..ae7f6787d124 100644
--- a/unit-tests/varmod-assign.exp
+++ b/unit-tests/varmod-assign.exp
@@ -61,6 +61,9 @@ make: Unfinished modifier after "value	# missing closing brace", expecting "}"
 	in target "mod-assign-parse-3"
 ok=word
 make: warning: Command " echo word; (exit 13) " exited with status 13
+	while evaluating variable "SH_ERR" with value "previous"
+	in command "@${SH_ERR::!= echo word; (exit 13) } echo err=${SH_ERR}"
+	in target "mod-assign-shell-error"
 err=previous
 Command: TARGET_CMD_VAR = cmd-value
 Global: TARGET_GLOBAL_VAR = global-value
diff --git a/unit-tests/varmod-ifelse.exp b/unit-tests/varmod-ifelse.exp
index d92134a83c84..039f0fd0b9a7 100644
--- a/unit-tests/varmod-ifelse.exp
+++ b/unit-tests/varmod-ifelse.exp
@@ -57,6 +57,15 @@ make: varmod-ifelse.mk:314: Unknown modifier ":X-then"
 make: varmod-ifelse.mk:314: Unknown modifier ":X-else"
 	while parsing "${:X-else}}"
 	while evaluating else-branch of condition "1"
+make: varmod-ifelse.mk:322: Bad condition
+	while evaluating condition " < 0 "
+make: varmod-ifelse.mk:322: Unknown modifier ":Z1"
+	while parsing "${:Z1}:${:Z2}}>"
+	while evaluating then-branch of condition " < 0 "
+make: varmod-ifelse.mk:322: Unknown modifier ":Z2"
+	while parsing "${:Z2}}>"
+	while evaluating else-branch of condition " < 0 "
+make: varmod-ifelse.mk:322: <>
 make: Fatal errors encountered -- cannot continue
 make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/varmod-ifelse.mk b/unit-tests/varmod-ifelse.mk
index c316da51c3a9..986524330a97 100644
--- a/unit-tests/varmod-ifelse.mk
+++ b/unit-tests/varmod-ifelse.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-ifelse.mk,v 1.37 2025/04/04 18:57:01 rillig Exp $
+# $NetBSD: varmod-ifelse.mk,v 1.39 2025/04/30 06:01:07 rillig Exp $
 #
 # Tests for the ${cond:?then:else} variable modifier, which evaluates either
 # the then-expression or the else-expression, depending on the condition.
@@ -313,3 +313,10 @@ BOTH=	<${YES}> <${NO}>
 # expect+1: Unknown modifier ":X-else"
 .if ${1:?${:X-then}:${:X-else}}
 .endif
+
+
+# expect+4: Bad condition
+# expect+3: Unknown modifier ":Z1"
+# expect+2: Unknown modifier ":Z2"
+# expect+1: <>
+.info <${ < 0 :?${:Z1}:${:Z2}}>
diff --git a/unit-tests/varmod-mtime.exp b/unit-tests/varmod-mtime.exp
index 538294b2cc7f..9960dd877768 100644
--- a/unit-tests/varmod-mtime.exp
+++ b/unit-tests/varmod-mtime.exp
@@ -1,8 +1,8 @@
 make: varmod-mtime.mk:46: Invalid argument '123x' for modifier ':mtime'
 	while evaluating variable "no/such/file" with value "no/such/file"
-make: varmod-mtime.mk:68: Cannot determine mtime for 'no/such/file1': <ENOENT>
+make: varmod-mtime.mk:68: Cannot determine mtime for "no/such/file1": <ENOENT>
 	while evaluating variable "no/such/file1 no/such/file2" with value "no/such/file1 no/such/file2"
-make: varmod-mtime.mk:68: Cannot determine mtime for 'no/such/file2': <ENOENT>
+make: varmod-mtime.mk:68: Cannot determine mtime for "no/such/file2": <ENOENT>
 	while evaluating variable "no/such/file1 no/such/file2" with value "no/such/file1 no/such/file2"
 make: varmod-mtime.mk:78: Invalid argument 'errorhandler-no' for modifier ':mtime'
 	while evaluating variable "MAKEFILE" with value "varmod-mtime.mk"
diff --git a/unit-tests/varmod-mtime.mk b/unit-tests/varmod-mtime.mk
index 67bca7c9d557..ec33cd698b41 100644
--- a/unit-tests/varmod-mtime.mk
+++ b/unit-tests/varmod-mtime.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varmod-mtime.mk,v 1.15 2025/03/29 19:08:52 rillig Exp $
+# $NetBSD: varmod-mtime.mk,v 1.16 2025/06/12 18:51:05 rillig Exp $
 #
 # Tests for the ':mtime' variable modifier, which maps each word of the
 # expression to that file's modification time.
@@ -63,8 +63,8 @@ _!=	rm -f ${COOKIE}
 # If the optional argument of the ':mtime' modifier is the word 'error', the
 # modifier fails with an error message, once for each affected file.
 #
-# expect+2: Cannot determine mtime for 'no/such/file1': <ENOENT>
-# expect+1: Cannot determine mtime for 'no/such/file2': <ENOENT>
+# expect+2: Cannot determine mtime for "no/such/file1": <ENOENT>
+# expect+1: Cannot determine mtime for "no/such/file2": <ENOENT>
 .if ${no/such/file1 no/such/file2:L:mtime=error}
 .  error
 .else
diff --git a/unit-tests/varname-dot-make-level.exp b/unit-tests/varname-dot-make-level.exp
index 63dcf58c6569..1209cf3b4af8 100644
--- a/unit-tests/varname-dot-make-level.exp
+++ b/unit-tests/varname-dot-make-level.exp
@@ -5,6 +5,7 @@ level 3: variable 2, env 3
 ok
 : set-env-different
 make: Cannot override read-only global variable ".MAKE.LEVEL.ENV" with a command line variable
+	in make[1] in directory "<curdir>"
 make: Fatal errors encountered -- cannot continue
 make: stopped making "ok" in unit-tests
 set-env-different: exit 1
diff --git a/unit-tests/varname-dot-makeflags.mk b/unit-tests/varname-dot-makeflags.mk
index ffb09decb70e..87e4e4443cd2 100644
--- a/unit-tests/varname-dot-makeflags.mk
+++ b/unit-tests/varname-dot-makeflags.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varname-dot-makeflags.mk,v 1.8 2023/06/01 20:56:35 rillig Exp $
+# $NetBSD: varname-dot-makeflags.mk,v 1.11 2025/05/20 17:56:40 sjg Exp $
 #
 # Tests for the special .MAKEFLAGS variable, which collects almost all
 # command line arguments and passes them on to any child processes via
diff --git a/unit-tests/varname-dot-newline.exp b/unit-tests/varname-dot-newline.exp
index 6358d076ed5f..12114c9f24fd 100644
--- a/unit-tests/varname-dot-newline.exp
+++ b/unit-tests/varname-dot-newline.exp
@@ -1,9 +1,9 @@
 make: varname-dot-newline.mk:28: Cannot overwrite ".newline" as it is read-only
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: varname-dot-newline.mk:30: Cannot append to ".newline" as it is read-only
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: varname-dot-newline.mk:32: Cannot delete ".newline" as it is read-only
-	in directory <curdir>
+	in make[1] in directory "<curdir>"
 make: Fatal errors encountered -- cannot continue
 make: stopped making "try-to-modify" in unit-tests
 first
diff --git a/unit-tests/varname-make_stack_trace.exp b/unit-tests/varname-make_stack_trace.exp
new file mode 100644
index 000000000000..c0f46cc5aa1e
--- /dev/null
+++ b/unit-tests/varname-make_stack_trace.exp
@@ -0,0 +1,40 @@
+make: Unknown modifier ":Z"
+	while evaluating "${:Z}" with value ""
+	in command "@echo ${:Z}"
+	in target "provoke-error"
+	in make[2] in directory "<curdir>"
+*** Error code 2 (continuing)
+
+Stop.
+make: stopped making "disabled-compat" in unit-tests
+make: Unknown modifier ":Z"
+	while evaluating "${:Z}" with value ""
+	in command "@echo ${:Z}"
+	in target "provoke-error"
+	in make[2] in directory "<curdir>"
+*** [disabled-parallel] Error code 2
+
+make: stopped making "disabled-parallel" in unit-tests
+make: Unknown modifier ":Z"
+	while evaluating "${:Z}" with value ""
+	in command "@echo ${:Z}"
+	in target "provoke-error"
+	in make[2] in directory "<curdir>"
+	in command "make -f varname-make_stack_trace.mk provoke-error"
+	in target "enabled-compat"
+	in make[1] in directory "<curdir>"
+*** Error code 2 (continuing)
+
+Stop.
+make: stopped making "enabled-compat" in unit-tests
+make: Unknown modifier ":Z"
+	while evaluating "${:Z}" with value ""
+	in command "@echo ${:Z}"
+	in target "provoke-error"
+	in make[2] in directory "<curdir>"
+	in target "enabled-parallel"
+	in make[1] in directory "<curdir>"
+*** [enabled-parallel] Error code 2
+
+make: stopped making "enabled-parallel" in unit-tests
+exit status 0
diff --git a/unit-tests/varname-make_stack_trace.mk b/unit-tests/varname-make_stack_trace.mk
new file mode 100644
index 000000000000..cba02559bafe
--- /dev/null
+++ b/unit-tests/varname-make_stack_trace.mk
@@ -0,0 +1,37 @@
+# $NetBSD: varname-make_stack_trace.mk,v 1.1 2025/06/13 03:51:18 rillig Exp $
+#
+# Tests for the MAKE_STACK_TRACE environment variable, which controls whether
+# to print inter-process stack traces that are useful to narrow down where an
+# erroneous expression comes from.
+#
+# While inter-process stack traces are useful to narrow down errors, they are
+# disabled by default since the stack trace is stored in an environment
+# variable and a stack trace can grow large depending on the shell commands in
+# the sub-make processes.  The space used for the stack traces would compete
+# with the space for the command line arguments, and long command lines are
+# already written to a temporary file by Cmd_Exec to not overwhelm this space.
+
+all: .PHONY
+	@${MAKE} -f ${MAKEFILE} disabled-compat || :
+	@${MAKE} -f ${MAKEFILE} -j1 disabled-parallel || :
+	@MAKE_STACK_TRACE=yes ${MAKE} -f ${MAKEFILE} enabled-compat || :
+	@MAKE_STACK_TRACE=yes ${MAKE} -f ${MAKEFILE} -j1 enabled-parallel || :
+
+# expect-not: in target "disabled-compat"
+disabled-compat: .PHONY
+	@${MAKE} -f ${MAKEFILE} provoke-error
+
+# expect-not: in target "disabled-parallel"
+disabled-parallel: .PHONY
+	@${MAKE} -f ${MAKEFILE} provoke-error
+
+# expect: in target "enabled-compat"
+enabled-compat: .PHONY
+	@${MAKE} -f ${MAKEFILE} provoke-error
+
+# expect: in target "enabled-parallel"
+enabled-parallel: .PHONY
+	@${MAKE} -f ${MAKEFILE} provoke-error
+
+provoke-error: .PHONY
+	@echo ${:Z}
diff --git a/unit-tests/varname.exp b/unit-tests/varname.exp
index 4886477c6125..d173d2025e9f 100644
--- a/unit-tests/varname.exp
+++ b/unit-tests/varname.exp
@@ -5,17 +5,26 @@ Var_Parse: ${VARNAME} (eval)
 Global: VAR((( = 3 open parentheses
 Var_Parse: ${VAR(((}}}}" != "3 open parentheses}}}" (eval)
 Global: .ALLTARGETS =  VAR(((=)
-make: varname.mk:32: Missing ')' in archive specification
-make: varname.mk:32: Error in archive specification: "VAR"
+make: varname.mk:31: Missing ')' in archive specification
+make: varname.mk:31: Error in archive specification: "VAR"
 Var_Parse: ${:UVAR\(\(\(}=	try2 (eval)
 Evaluating modifier ${:U...} on value "" (eval, undefined)
 Result of ${:UVAR\(\(\(} is "VAR\(\(\(" (eval, defined)
 Global: .ALLTARGETS =  VAR(((=) VAR\(\(\(=
-make: varname.mk:38: Invalid line '${:UVAR\(\(\(}=	try2', expanded to 'VAR\(\(\(=	try2'
+make: varname.mk:37: Invalid line '${:UVAR\(\(\(}=	try2', expanded to 'VAR\(\(\(=	try2'
 Var_Parse: ${VARNAME} (eval)
 Global: VAR((( = try3
 Global: .MAKEFLAGS =  -r -k -d v -d
 Global: .MAKEFLAGS =  -r -k -d v -d 0
+make: varname.mk:98: warning: Invalid character " " in variable name "if ,yes,no"
+make: varname.mk:113: warning: Invalid character " " in variable name "if ,yes,no"
+make: varname.mk:120: warning: Invalid character " " in variable name "if ,,"
+make: varname.mk:128: Unknown modifier ":yes,answer"
+	while evaluating variable "if ,answer" with value ""
+	while evaluating variable "GNU_MAKE_IF_MODIFIER" with value "$(if ${HAVE_STRLEN},answer:yes,answer:no)"
+make: varname.mk:138: warning: Invalid character "\x09" in variable name "a	b"
+make: varname.mk:138: Variable "a	b" is undefined
+make: varname.mk:144: Variable "ÄÖÜ" is undefined
 make: Fatal errors encountered -- cannot continue
-make: stopped making "all" in unit-tests
+make: stopped in unit-tests
 exit status 1
diff --git a/unit-tests/varname.mk b/unit-tests/varname.mk
index d2c36afb3aa2..ae18819aa19e 100644
--- a/unit-tests/varname.mk
+++ b/unit-tests/varname.mk
@@ -1,12 +1,11 @@
-# $NetBSD: varname.mk,v 1.16 2025/01/11 20:16:40 rillig Exp $
+# $NetBSD: varname.mk,v 1.17 2025/06/12 04:33:00 rillig Exp $
 #
-# Tests for special variables, such as .MAKE or .PARSEDIR.
-# And for variable names in general.
+# Tests for variable names.
 
 .MAKEFLAGS: -dv
 
-# In variable names, braces are allowed, but they must be balanced.
-# Parentheses and braces may be mixed.
+# In a variable assignment, braces are allowed in the variable name, but they
+# must be balanced.  Parentheses and braces may be mixed.
 VAR{{{}}}=	3 braces
 .if "${VAR{{{}}}}" != "3 braces"
 .  error
@@ -86,4 +85,61 @@ ASDZguv.param=		once
 .  error
 .endif
 
-all:
+
+# Warn about expressions in the style of GNU make, as these would silently
+# expand to an empty string instead.
+#
+# https://pubs.opengroup.org/onlinepubs/9799919799/utilities/make.html says:
+#	a macro name shall not contain an <equals-sign>, <blank>, or control
+#	character.
+#
+GNU_MAKE_IF=	$(if ${HAVE_STRLEN},yes,no)
+# expect+1: warning: Invalid character " " in variable name "if ,yes,no"
+.if ${GNU_MAKE_IF} != ""
+.  error
+.endif
+#
+# This requirement needs to be ignored for expressions with a ":L" or ":?:"
+# modifier, as these modifiers rely on arbitrary characters in the expression
+# name.
+.if ${"left" == "right":?equal:unequal} != "unequal"
+.  error
+.endif
+#
+# In fact, this requirement is ignored for any expression that has a modifier.
+# In this indirect case, though, the expression with the space in the name is
+# a nested expression, so the ":U" modifier doesn't affect the warning.
+# expect+1: warning: Invalid character " " in variable name "if ,yes,no"
+.if ${GNU_MAKE_IF:Ufallback} != ""
+.  error
+.endif
+#
+# A modifier in a nested expression does not affect the warning.
+GNU_MAKE_IF_EXPR=	$(if ${HAVE_STRLEN},${HEADERS:.h=.c},)
+# expect+1: warning: Invalid character " " in variable name "if ,,"
+.if ${GNU_MAKE_IF_EXPR} != ""
+.  error
+.endif
+#
+# When the GNU make expression contains a colon, chances are good that the
+# colon is interpreted as an unknown modifier.
+GNU_MAKE_IF_MODIFIER=	$(if ${HAVE_STRLEN},answer:yes,answer:no)
+# expect+1: Unknown modifier ":yes,answer"
+.if ${GNU_MAKE_IF_MODIFIER} != "no)"
+.  error
+.endif
+#
+# If the variable name contains a non-printable character, the warning
+# contains the numeric character value instead, to prevent control sequences
+# in the output.
+CONTROL_CHARACTER=	${:U a b:ts\t}
+# expect+2: warning: Invalid character "\x09" in variable name "a	b"
+# expect+1: Variable "a	b" is undefined
+.if ${${CONTROL_CHARACTER}} != ""
+.endif
+#
+# For now, only whitespace generates a warning, non-ASCII characters don't.
+UMLAUT=		ÄÖÜ
+# expect+1: Variable "ÄÖÜ" is undefined
+.if ${${UMLAUT}} != ""
+.endif
diff --git a/unit-tests/varparse-errors.mk b/unit-tests/varparse-errors.mk
index 921f2229f102..2d1142fbb65c 100644
--- a/unit-tests/varparse-errors.mk
+++ b/unit-tests/varparse-errors.mk
@@ -1,4 +1,4 @@
-# $NetBSD: varparse-errors.mk,v 1.24 2025/03/30 09:51:51 rillig Exp $
+# $NetBSD: varparse-errors.mk,v 1.25 2025/05/03 08:18:33 rillig Exp $
 
 # Tests for parsing and evaluating all kinds of expressions.
 #
@@ -122,6 +122,6 @@ UNCLOSED:=	${:U:localtime
 _!=	echo '.info $${VALUE}' > varparse-errors.tmp
 VALUE=	${INDIRECT}
 INDIRECT=	${:Z}
-# The "${.OBJDIR}/" is necessary to skip the directory cache.
+# The "${.OBJDIR}/" is necessary to bypass the directory cache.
 .include "${.OBJDIR}/varparse-errors.tmp"
 _!=	rm -f varparse-errors.tmp
diff --git a/var.c b/var.c
index 68668243cc5f..55d20bd324ac 100644
--- a/var.c
+++ b/var.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: var.c,v 1.1159 2025/04/04 18:57:01 rillig Exp $	*/
+/*	$NetBSD: var.c,v 1.1168 2025/06/13 18:31:08 rillig Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1993
@@ -143,7 +143,7 @@
 #endif
 
 /*	"@(#)var.c	8.3 (Berkeley) 3/19/94" */
-MAKE_RCSID("$NetBSD: var.c,v 1.1159 2025/04/04 18:57:01 rillig Exp $");
+MAKE_RCSID("$NetBSD: var.c,v 1.1168 2025/06/13 18:31:08 rillig Exp $");
 
 /*
  * Variables are defined using one of the VAR=value assignments.  Their
@@ -271,6 +271,7 @@ typedef struct SepBuf {
 } SepBuf;
 
 typedef enum {
+	VSK_MAKEFLAGS,
 	VSK_TARGET,
 	VSK_COMMAND,
 	VSK_VARNAME,
@@ -378,7 +379,13 @@ EvalStack_Push(EvalStackElementKind kind, const char *str, const FStr *value)
 	evalStack.len++;
 }
 
-static void
+void
+EvalStack_PushMakeflags(const char *makeflags)
+{
+	EvalStack_Push(VSK_MAKEFLAGS, makeflags, NULL);
+}
+
+void
 EvalStack_Pop(void)
 {
 	assert(evalStack.len > 0);
@@ -386,12 +393,13 @@ EvalStack_Pop(void)
 }
 
 bool
-EvalStack_PrintDetails(void)
+EvalStack_Details(Buffer *buf)
 {
 	size_t i;
 
 	for (i = evalStack.len; i > 0; i--) {
 		static const char descr[][42] = {
+			"while evaluating MAKEFLAGS",
 			"in target",
 			"in command",
 			"while evaluating variable",
@@ -408,9 +416,15 @@ EvalStack_PrintDetails(void)
 		    && (kind == VSK_VARNAME || kind == VSK_EXPR)
 		    ? elem->value->str : NULL;
 
-		debug_printf("\t%s \"%s%s%s\"\n", descr[kind], elem->str,
-		    value != NULL ? "\" with value \"" : "",
-		    value != NULL ? value : "");
+		Buf_AddStr(buf, "\t");
+		Buf_AddStr(buf, descr[kind]);
+		Buf_AddStr(buf, " \"");
+		Buf_AddStr(buf, elem->str);
+		if (value != NULL) {
+			Buf_AddStr(buf, "\" with value \"");
+			Buf_AddStr(buf, value);
+		}
+		Buf_AddStr(buf, "\"\n");
 	}
 	return evalStack.len > 0;
 }
@@ -466,7 +480,7 @@ CanonicalVarname(Substring name)
 }
 
 static Var *
-GNode_FindVar(GNode *scope, Substring varname, unsigned int hash)
+GNode_FindVar(GNode *scope, Substring varname, unsigned hash)
 {
 	return HashTable_FindValueBySubstringHash(&scope->vars, varname, hash);
 }
@@ -488,7 +502,7 @@ static Var *
 VarFindSubstring(Substring name, GNode *scope, bool elsewhere)
 {
 	Var *var;
-	unsigned int nameHash;
+	unsigned nameHash;
 
 	/* Replace '.TARGET' with '@', likewise for other local variables. */
 	name = CanonicalVarname(name);
@@ -1600,7 +1614,7 @@ static void
 RegexReplaceBackref(char ref, SepBuf *buf, const char *wp,
 		    const regmatch_t *m, size_t nsub)
 {
-	unsigned int n = (unsigned)ref - '0';
+	unsigned n = (unsigned)ref - '0';
 
 	if (n >= nsub)
 		Parse_Error(PARSE_FATAL, "No subexpression \\%u", n);
@@ -2868,7 +2882,7 @@ ModifyWord_Mtime(Substring word, SepBuf *buf, void *data)
 	if (stat(word.start, &st) < 0) {
 		if (args->error) {
 			Parse_Error(PARSE_FATAL,
-			    "Cannot determine mtime for '%s': %s",
+			    "Cannot determine mtime for \"%s\": %s",
 			    word.start, strerror(errno));
 			args->rc = AMR_CLEANUP;
 			return;
@@ -3481,7 +3495,7 @@ ApplyModifier_IfElse(const char **pp, ModChain *ch)
 
 	VarEvalMode then_emode = VARE_PARSE;
 	VarEvalMode else_emode = VARE_PARSE;
-	int parseErrorsBefore = parseErrors, parseErrorsAfter = parseErrors;
+	int parseErrorsBefore = parseErrors;
 
 	CondResult cond_rc = CR_TRUE;	/* anything other than CR_ERROR */
 	if (Expr_ShouldEval(expr)) {
@@ -3489,9 +3503,10 @@ ApplyModifier_IfElse(const char **pp, ModChain *ch)
 		cond_rc = Cond_EvalCondition(expr->name);
 		if (cond_rc == CR_TRUE)
 			then_emode = expr->emode;
-		if (cond_rc == CR_FALSE)
+		else if (cond_rc == CR_FALSE)
 			else_emode = expr->emode;
-		parseErrorsAfter = parseErrors;
+		else if (parseErrors == parseErrorsBefore)
+			Parse_Error(PARSE_FATAL, "Bad condition");
 	}
 
 	evalStack.elems[evalStack.len - 1].kind = VSK_COND_THEN;
@@ -3510,9 +3525,6 @@ ApplyModifier_IfElse(const char **pp, ModChain *ch)
 	(*pp)--;		/* Go back to the ch->endc. */
 
 	if (cond_rc == CR_ERROR) {
-		evalStack.elems[evalStack.len - 1].kind = VSK_COND;
-		if (parseErrorsAfter == parseErrorsBefore)
-			Parse_Error(PARSE_FATAL, "Bad condition");
 		LazyBuf_Done(&thenBuf);
 		LazyBuf_Done(&elseBuf);
 		return AMR_CLEANUP;
@@ -3578,9 +3590,9 @@ found_op:
 		/* Take a guess at where the modifier ends. */
 		Parse_Error(PARSE_FATAL,
 		    "Invalid attempt to assign \"%.*s\" to variable \"\" "
-		    "via modifier \"::%.*s\"",
+		    "via modifier \":%.*s\"",
 		    (int)strcspn(value, ":)}"), value,
-		    (int)(value - op), op);
+		    (int)(value - mod), mod);
 		return AMR_CLEANUP;
 	}
 
@@ -3693,15 +3705,9 @@ ApplyModifier_Unique(const char **pp, ModChain *ch)
 
 	if (words.len > 1) {
 		size_t di, si;
-
-		di = 0;
-		for (si = 1; si < words.len; si++) {
-			if (!Substring_Eq(words.words[si], words.words[di])) {
-				di++;
-				if (di != si)
-					words.words[di] = words.words[si];
-			}
-		}
+		for (di = 0, si = 1; si < words.len; si++)
+			if (!Substring_Eq(words.words[di], words.words[si]))
+				words.words[++di] = words.words[si];
 		words.len = di + 1;
 	}
 
@@ -4358,6 +4364,25 @@ EvalUndefined(bool dynamic, const char *start, const char *p,
 		? var_Error : varUndefined);
 }
 
+static void
+CheckVarname(Substring name)
+{
+	const char *p;
+
+	for (p = name.start; p < name.end; p++) {
+		if (ch_isspace(*p))
+			break;
+	}
+	if (p < name.end) {
+		Parse_Error(PARSE_WARNING,
+		    ch_isprint(*p)
+		    ? "Invalid character \"%c\" in variable name \"%.*s\""
+		    : "Invalid character \"\\x%02x\" in variable name \"%.*s\"",
+		    (int)(*p),
+		    (int)Substring_Length(name), name.start);
+	}
+}
+
 /*
  * Parse a long variable name enclosed in braces or parentheses such as $(VAR)
  * or ${VAR}, up to the closing brace or parenthesis, or in the case of
@@ -4435,6 +4460,7 @@ ParseVarnameLong(
 			  (scope == SCOPE_CMDLINE || scope == SCOPE_GLOBAL);
 
 		if (!haveModifier) {
+			CheckVarname(name);
 			p++;	/* skip endc */
 			*out_false_pp = p;
 			*out_false_val = EvalUndefined(dynamic, start, p,
@@ -4674,6 +4700,8 @@ Var_Parse(const char **pp, GNode *scope, VarEvalMode emode)
 		Expr_SetValue(&expr, value);
 	}
 
+	EvalStack_Pop();
+
 	if (v->shortLived) {
 		if (expr.value.str == v->val.data) {
 			/* move ownership */
@@ -4683,7 +4711,6 @@ Var_Parse(const char **pp, GNode *scope, VarEvalMode emode)
 		VarFreeShortLived(v);
 	}
 
-	EvalStack_Pop();
 	return expr.value;
 }
 
@@ -4788,6 +4815,29 @@ Var_SubstInTarget(const char *str, GNode *scope)
 }
 
 void
+Var_ExportStackTrace(const char *target, const char *cmd)
+{
+	char *stackTrace;
+
+	if (GetParentStackTrace() == NULL)
+		return;
+
+	if (target != NULL)
+		EvalStack_Push(VSK_TARGET, target, NULL);
+	if (cmd != NULL)
+		EvalStack_Push(VSK_COMMAND, cmd, NULL);
+
+	stackTrace = GetStackTrace(true);
+	(void)setenv("MAKE_STACK_TRACE", stackTrace, 1);
+	free(stackTrace);
+
+	if (cmd != NULL)
+		EvalStack_Pop();
+	if (target != NULL)
+		EvalStack_Pop();
+}
+
+void
 Var_Expand(FStr *str, GNode *scope, VarEvalMode emode)
 {
 	char *expanded;