re PR driver/46944 (gcc should accept -fuse-linker-plugin only if linker handles -plugin)

	PR lto/46944
	* configure.ac (gcc_cv_gld_major_version, gcc_cv_gld_minor):
	Handle in-tree gold.
	(ld_vers): Extract binutils version for gold.
	(gcc_cv_ld_hidden): Handle gold here.
	(gcc_cv_lto_plugin): Determine level of linker plugin support.
	* configure: Regenerate.
	* config.in: Regenerate.
	* gcc.c: Only use LTO plugin if HAVE_LTO_PLUGIN > 0, reject
	-fuse-linker-plugin otherwise.
	(LINK_PLUGIN_SPEC): Define.  Extract from LINK_COMMAND_SPEC.
	(LINK_COMMAND_SPEC): Use it.
	(main): Only look for LTOPLUGINSONAME if HAVE_LTO_PLUGIN > 0.

From-SVN: r171039

1 files changed, 41 insertions, 18 deletions

diff --git a/gcc/configure b/gcc/configure
index e5e6164..a2f78c3 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -21096,7 +21096,8 @@ esac
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking what linker to use" >&5
 $as_echo_n "checking what linker to use... " >&6; }
-if test "$gcc_cv_ld" = ../ld/ld-new$build_exeext; then
+if test "$gcc_cv_ld" = ../ld/ld-new$build_exeext \
+   || test "$gcc_cv_ld" = ../gold/ld-new$build_exeext; then
 	# Single tree build which includes ld.  We want to prefer it
 	# over whatever linker top-level may have detected, since
 	# we'll use what we're building after installation anyway.
@@ -21108,6 +21109,8 @@ $as_echo "newly built ld" >&6; }
 	    || grep 'EMUL = .*linux' ../ld/Makefile \
 	    || grep 'EMUL = .*lynx' ../ld/Makefile) > /dev/null; then
 	  in_tree_ld_is_elf=yes
+	elif test "$ld_is_gold" = yes; then
+	  in_tree_ld_is_elf=yes
 	fi
 	for f in $gcc_cv_ld_bfd_srcdir/configure $gcc_cv_ld_gld_srcdir/configure $gcc_cv_ld_gld_srcdir/configure.in $gcc_cv_ld_gld_srcdir/Makefile.in
 	do
@@ -21716,11 +21719,23 @@ fi
 
 if test $in_tree_ld != yes ; then
   ld_ver=`$gcc_cv_ld --version 2>/dev/null | sed 1q`
-  if test x"$ld_is_gold" = xyes; then
-    gcc_cv_ld_hidden=yes
-  elif echo "$ld_ver" | grep GNU > /dev/null; then
-    ld_vers=`echo $ld_ver | sed -n \
-	-e 's,^.*[	 ]\([0-9][0-9]*\.[0-9][0-9]*.*\)$,\1,p'`
+  if echo "$ld_ver" | grep GNU > /dev/null; then
+    if test x"$ld_is_gold" = xyes; then
+      # GNU gold --version looks like this:
+      #
+      # GNU gold (GNU Binutils 2.21.51.20110225) 1.11
+      #
+      # We extract the binutils version which is more familiar and specific
+      # than the gold version.
+      ld_vers=`echo $ld_ver | sed -n \
+	  -e 's,^[^)]*[	 ]\([0-9][0-9]*\.[0-9][0-9]*[^)]*\)) .*$,\1,p'`
+    else
+      # GNU ld --version looks like this:
+      #
+      # GNU ld (GNU Binutils) 2.21.51.20110225
+      ld_vers=`echo $ld_ver | sed -n \
+	  -e 's,^.*[	 ]\([0-9][0-9]*\.[0-9][0-9]*.*\)$,\1,p'`
+    fi
     ld_date=`echo $ld_ver | sed -n 's,^.*\([2-9][0-9][0-9][0-9]\)[-]*\([01][0-9]\)[-]*\([0-3][0-9]\).*$,\1\2\3,p'`
     ld_vers_major=`expr "$ld_vers" : '\([0-9]*\)'`
     ld_vers_minor=`expr "$ld_vers" : '[0-9]*\.\([0-9]*\)'`
@@ -21762,7 +21777,9 @@ else
   fi
 else
   gcc_cv_ld_hidden=yes
-  if echo "$ld_ver" | grep GNU > /dev/null; then
+  if test x"$ld_is_gold" = xyes; then
+    :
+  elif echo "$ld_ver" | grep GNU > /dev/null; then
     if test 0"$ld_date" -lt 20020404; then
       if test -n "$ld_date"; then
 	# If there was date string, but was earlier than 2002-04-04, fail
@@ -23115,24 +23132,30 @@ fi
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking linker plugin support" >&5
 $as_echo_n "checking linker plugin support... " >&6; }
-gcc_cv_lto_plugin=no
+gcc_cv_lto_plugin=0
 if test -f liblto_plugin.la; then
   if test $in_tree_ld = yes -a x"$ORIGINAL_PLUGIN_LD_FOR_TARGET=" = x"$gcc_cv_ld"; then
-    if test x"$ld_is_gold" = xyes; then
-      gcc_cv_lto_plugin=yes
-    elif test "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -ge 21 -o "$gcc_cv_gld_major_version" -gt 2; then \
-      gcc_cv_lto_plugin=yes
+    if test "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -ge 21 -o "$gcc_cv_gld_major_version" -gt 2; then
+      gcc_cv_lto_plugin=2
+    elif test "$ld_is_gold" = yes -a "$gcc_cv_gld_major_version" -eq 2 -a "$gcc_cv_gld_minor_version" -eq 20; then
+      gcc_cv_lto_plugin=1
+
+    fi
+  elif echo "$ld_ver" | grep GNU > /dev/null; then
+    # Require GNU ld or gold 2.21+ for plugin support by default.
+    if test "$ld_vers_major" -eq 2 -a "$ld_vers_minor" -ge 21; then
+      gcc_cv_lto_plugin=2
+    # Allow -fuse-linker-plugin to enable plugin support in GNU gold 2.20.
+    elif test "$ld_is_gold" = yes -a "$ld_vers_major" -eq 2 -a "$ld_vers_minor" -eq 20; then
+      gcc_cv_lto_plugin=1
     fi
-  # Check if the linker supports --plugin-opt option
-  elif $ORIGINAL_PLUGIN_LD_FOR_TARGET --help 2>/dev/null | grep plugin-opt > /dev/null; then
-    gcc_cv_lto_plugin=yes
   fi
 fi
-if test x"$gcc_cv_lto_plugin" = xyes; then
 
-$as_echo "#define HAVE_LTO_PLUGIN 1" >>confdefs.h
+cat >>confdefs.h <<_ACEOF
+#define HAVE_LTO_PLUGIN $gcc_cv_lto_plugin
+_ACEOF
 
-fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_lto_plugin" >&5
 $as_echo "$gcc_cv_lto_plugin" >&6; }