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[PATCH] Fix linking C executables/shared libraries which use __attribute__((cleanup ()))

Hi!

Alan recently implemented support for conditional linking of shared
libraries.  The follwoing patch is the GCC side of the needed changes.
Without it for example gcc 3.4+ compiled NPTL C programs using
pthread_cleanup_{push,pop} will not handle cancellation properly.
This patch just changes the default behaviour, when neither -static-libgcc
nor -shared-libgcc is specified.  The program or shared library will be
linked against libgcc_s if EH is used and just against libgcc.a if not.
Ok to commit?
For 3.4/3.3 as well (bootstrapped/regtested in 3.4 on x86_64-redhat-linux
so far)?

2004-03-27  Alan Modra  <amodra@bigpond.net.au>
	    Jakub Jelinek  <jakub@redhat.com>

	* gcc.c (init_gcc_specs): If HAVE_LD_AS_NEEDED, link with
	-lgcc --as-needed -lgcc_s --no-as-needed by default.
	* configure.ac (HAVE_LD_AS_NEEDED): Check for ld --as-needed.
	* configure: Rebuilt.
	* config.in: Rebuilt.

--- gcc/gcc.c.jj	2004-03-08 18:49:01.000000000 +0100
+++ gcc/gcc.c	2004-03-27 10:20:10.651163833 +0100
@@ -1531,6 +1531,12 @@ init_gcc_specs (struct obstack *obstack,
 
   buf = concat ("%{static|static-libgcc:", static_name, " ", eh_name,
 		"}%{!static:%{!static-libgcc:",
+#ifdef HAVE_LD_AS_NEEDED
+		"%{!shared-libgcc:", static_name,
+		" --as-needed ", shared_name, " --no-as-needed}"
+		"%{shared-libgcc:", shared_name, "%{!shared: ", static_name,
+		"}",
+#else
 		"%{!shared:%{!shared-libgcc:", static_name, " ",
 		eh_name, "}%{shared-libgcc:", shared_name, " ",
 		static_name, "}}%{shared:",
@@ -1540,6 +1546,7 @@ init_gcc_specs (struct obstack *obstack,
 #else
 		shared_name,
 #endif
+#endif
 		"}}}", NULL);
 
   obstack_grow (obstack, buf, strlen (buf));
--- gcc/configure.ac.jj	2004-03-08 18:49:00.000000000 +0100
+++ gcc/configure.ac	2004-03-27 09:53:42.912708012 +0100
@@ -2627,6 +2627,25 @@ if test x"$gcc_cv_ld_pie" = xyes; then
 fi
 AC_MSG_RESULT($gcc_cv_ld_pie)
 
+AC_MSG_CHECKING(linker --as-needed support)
+gcc_cv_ld_as_needed=no
+if test $in_tree_ld = yes ; then
+  if test "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -ge 16 -o "$gcc_cv_gld_major_version" -gt 2 \
+     && test $in_tree_ld_is_elf = yes; then
+    gcc_cv_ld_as_needed=yes
+  fi
+elif test x$gcc_cv_ld != x; then
+	# Check if linker supports --as-needed and --no-as-needed options
+	if $gcc_cv_ld --help 2>/dev/null | grep as-needed > /dev/null; then
+		gcc_cv_ld_as_needed=yes
+	fi
+fi
+if test x"$gcc_cv_ld_as_needed" = xyes; then
+	AC_DEFINE(HAVE_LD_AS_NEEDED, 1,
+[Define if your linker supports --as-needed and --no-as-needed options.])
+fi
+AC_MSG_RESULT($gcc_cv_ld_as_needed)
+
 if test x$with_sysroot = x && test x$host = x$target \
    && test "$prefix" != "/usr" && test "x$prefix" != "x$local_prefix" ; then
   AC_DEFINE_UNQUOTED(PREFIX_INCLUDE_DIR, "$prefix/include",
--- gcc/configure.jj	2004-03-16 16:24:42.000000000 +0100
+++ gcc/configure	2004-03-27 09:56:51.886841295 +0100
@@ -11311,6 +11311,30 @@ fi
 echo "$as_me:$LINENO: result: $gcc_cv_ld_pie" >&5
 echo "${ECHO_T}$gcc_cv_ld_pie" >&6
 
+echo "$as_me:$LINENO: checking linker --as-needed support" >&5
+echo $ECHO_N "checking linker --as-needed support... $ECHO_C" >&6
+gcc_cv_ld_as_needed=no
+if test $in_tree_ld = yes ; then
+  if test "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -ge 16 -o "$gcc_cv_gld_major_version" -gt 2 \
+     && test $in_tree_ld_is_elf = yes; then
+    gcc_cv_ld_as_needed=yes
+  fi
+elif test x$gcc_cv_ld != x; then
+	# Check if linker supports --as-needed and --no-as-needed options
+	if $gcc_cv_ld --help 2>/dev/null | grep as-needed > /dev/null; then
+		gcc_cv_ld_as_needed=yes
+	fi
+fi
+if test x"$gcc_cv_ld_as_needed" = xyes; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_LD_AS_NEEDED 1
+_ACEOF
+
+fi
+echo "$as_me:$LINENO: result: $gcc_cv_ld_as_needed" >&5
+echo "${ECHO_T}$gcc_cv_ld_as_needed" >&6
+
 if test x$with_sysroot = x && test x$host = x$target \
    && test "$prefix" != "/usr" && test "x$prefix" != "x$local_prefix" ; then
 
--- gcc/config.in.jj	2004-03-16 16:24:41.000000000 +0100
+++ gcc/config.in	2004-03-27 09:55:54.922050155 +0100
@@ -306,6 +306,9 @@
 /* Define to 1 if you have the <ldfcn.h> header file. */
 #undef HAVE_LDFCN_H
 
+/* Define if your linker supports --as-needed and --no-as-needed options. */
+#undef HAVE_LD_AS_NEEDED
+
 /* Define if your linker supports --eh-frame-hdr option. */
 #undef HAVE_LD_EH_FRAME_HDR
 

	Jakub
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