API dwarf_attrval_flag() should properly handle an attribute with

(DWARF4) form DW_FORM_flag_present which implicitly indicates the
presence of the attribute. Manual page is updated to reflect this
change.

Note that this was previously fixed in the old libdwarf.

2 files changed, 23 insertions, 7 deletions

diff --git a/contrib/elftoolchain/libdwarf/dwarf_attrval.c b/contrib/elftoolchain/libdwarf/dwarf_attrval.c
index 0f17016ad810..31d19f7b8b21 100644
--- a/contrib/elftoolchain/libdwarf/dwarf_attrval.c
+++ b/contrib/elftoolchain/libdwarf/dwarf_attrval.c
@@ -50,6 +50,7 @@ dwarf_attrval_flag(Dwarf_Die die, Dwarf_Half attr, Dwarf_Bool *valp, Dwarf_Error
 
 	switch (at->at_form) {
 	case DW_FORM_flag:
+	case DW_FORM_flag_present:
 		*valp = (Dwarf_Bool) (!!at->u[0].u64);
 		break;
 	default:
diff --git a/contrib/elftoolchain/libdwarf/dwarf_attrval_signed.3 b/contrib/elftoolchain/libdwarf/dwarf_attrval_signed.3
index 9646990fc2de..5888d08001a4 100644
--- a/contrib/elftoolchain/libdwarf/dwarf_attrval_signed.3
+++ b/contrib/elftoolchain/libdwarf/dwarf_attrval_signed.3
@@ -24,7 +24,7 @@
 .\"
 .\" $Id: dwarf_attrval_signed.3 2072 2011-10-27 03:26:49Z jkoshy $
 .\"
-.Dd January 29, 2011
+.Dd January 18, 2014
 .Os
 .Dt DWARF_ATTRVAL_SIGNED 3
 .Sh NAME
@@ -84,13 +84,28 @@ Function
 .Fn dwarf_attrval_flag
 sets the location pointed to by argument
 .Ar ret
-to 1 if the attribute named by argument
+to either 0 or 1. If the form of the attribute named by argument
 .Ar attr
-has a non-zero value, or to 0 otherwise.
-The form of the attribute named by argument
+is
+.Dv DW_FORM_flag ,
+function
+.Fn dwarf_attrval_flag
+sets the location pointed to by argument
+.Ar ret
+to 1 if the attribute has a non-zero value, or to 0 otherwise.
+If the form of the attribute named by argument
 .Ar attr
-must be
-.Dv DW_FORM_flag .
+is
+.Dv DW_FORM_flag_present , 
+function
+.Fn dwarf_attrval_flag
+unconditionally sets the location pointed to by argument
+.Ar ret
+to 1.
+The form of the attribute must be one of
+.Dv DW_FORM_flag
+or
+.Dv DW_FORM_flag_present .
 .Pp
 Function
 .Fn dwarf_attrval_signed
@@ -122,7 +137,7 @@ attribute named by argument
 The form of the attribute must be one of
 .Dv DW_FORM_string
 or
-.Dv  DW_FORM_strp .
+.Dv DW_FORM_strp .
 .Pp
 Function
 .Fn dwarf_attrval_unsigned