lang/ghc: Add RTS linker patch for the external interpreter.

1 files changed, 87 insertions, 0 deletions

diff --git a/lang/ghc/files/patch-rts-linker b/lang/ghc/files/patch-rts-linker
new file mode 100644
index 000000000000..feb736f72176
--- /dev/null
+++ b/lang/ghc/files/patch-rts-linker
@@ -0,0 +1,87 @@
+diff --git a/rts/Linker.c b/rts/Linker.c
+index 72533ae52af48184fb76171fb93a73c04d025f2f..09cf5fa0593743f9b9f44603e2290cea9132ed89 100644
+--- rts/Linker.c
++++ rts/Linker.c
+@@ -78,6 +78,33 @@
+ #if defined(dragonfly_HOST_OS)
+ #include <sys/tls.h>
+ #endif
++
++/*
++ * Note [iconv and FreeBSD]
++ * ~~~~~~~~~~~~~~~~~~~~~~~~
++ *
++ * On FreeBSD libc.so provides an implementation of the iconv_* family of
++ * functions. However, due to their implementation, these symbols cannot be
++ * resolved via dlsym(); rather, they can only be resolved using the
++ * explicitly-versioned dlvsym().
++ *
++ * This is problematic for the RTS linker since we may be asked to load
++ * an object that depends upon iconv. To handle this we include a set of
++ * fallback cases for these functions, allowing us to resolve them to the
++ * symbols provided by the libc against which the RTS is linked.
++ *
++ * See #20354.
++ */
++
++#if defined(freebsd_HOST_OS)
++extern void iconvctl();
++extern void iconv_open_into();
++extern void iconv_open();
++extern void iconv_close();
++extern void iconv_canonicalize();
++extern void iconv();
++#endif
++
+ /*
+    Note [runtime-linker-support]
+    -----------------------------
+@@ -655,6 +682,10 @@ internal_dlsym(const char *symbol) {
+     }
+     RELEASE_LOCK(&dl_mutex);
+ 
++    IF_DEBUG(linker, debugBelch("internal_dlsym: looking for symbol '%s' in special cases\n", symbol));
++#   define SPECIAL_SYMBOL(sym) \
++      if (strcmp(symbol, #sym) == 0) return (void*)&sym;
++
+ #   if defined(HAVE_SYS_STAT_H) && defined(linux_HOST_OS) && defined(__GLIBC__)
+     // HACK: GLIBC implements these functions with a great deal of trickery where
+     //       they are either inlined at compile time to their corresponding
+@@ -664,18 +695,28 @@ internal_dlsym(const char *symbol) {
+     //       We borrow the approach that the LLVM JIT uses to resolve these
+     //       symbols. See http://llvm.org/PR274 and #7072 for more info.
+ 
+-    IF_DEBUG(linker, debugBelch("internal_dlsym: looking for symbol '%s' in GLIBC special cases\n", symbol));
++    SPECIAL_SYMBOL(stat);
++    SPECIAL_SYMBOL(fstat);
++    SPECIAL_SYMBOL(lstat);
++    SPECIAL_SYMBOL(stat64);
++    SPECIAL_SYMBOL(fstat64);
++    SPECIAL_SYMBOL(lstat64);
++    SPECIAL_SYMBOL(atexit);
++    SPECIAL_SYMBOL(mknod);
++#   endif
+ 
+-    if (strcmp(symbol, "stat") == 0) return (void*)&stat;
+-    if (strcmp(symbol, "fstat") == 0) return (void*)&fstat;
+-    if (strcmp(symbol, "lstat") == 0) return (void*)&lstat;
+-    if (strcmp(symbol, "stat64") == 0) return (void*)&stat64;
+-    if (strcmp(symbol, "fstat64") == 0) return (void*)&fstat64;
+-    if (strcmp(symbol, "lstat64") == 0) return (void*)&lstat64;
+-    if (strcmp(symbol, "atexit") == 0) return (void*)&atexit;
+-    if (strcmp(symbol, "mknod") == 0) return (void*)&mknod;
++    // See Note [iconv and FreeBSD]
++#   if defined(freebsd_HOST_OS)
++    SPECIAL_SYMBOL(iconvctl);
++    SPECIAL_SYMBOL(iconv_open_into);
++    SPECIAL_SYMBOL(iconv_open);
++    SPECIAL_SYMBOL(iconv_close);
++    SPECIAL_SYMBOL(iconv_canonicalize);
++    SPECIAL_SYMBOL(iconv);
+ #   endif
+ 
++#undef SPECIAL_SYMBOL
++
+     // we failed to find the symbol
+     return NULL;
+ }