Richard Guenther<rguenther@suse.de> writes:
On Fri, 18 Mar 2011, Rainer Orth wrote:
Richard Guenther<richard.guenther@gmail.com> writes:
It seemed to have disabled linker-plugin support for old binutils
with --with-plugin-ld=/usr/local/bin/gold, explicit -fuse-linker-plugin says
it is not supported. The system linker does not have plugin support
(nor gold). /usr/local has gold from binutils 2.20.50.xxx. So it seems that
# 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
only allows explicit -fuse-linker-plugin for recent gold but based on checking
the system linker version (instead of that of --with-plugin-ld). I'd say
allow explicit -fuse-linker-plugin always if --with-plugin-ld is specified.
Agreed. I'll have a look and refrain from installing on 4.6 until this
is resolved. I wasn't even aware of --with-plugin-ld, which isn't
documented in install.texi ;-( This stuff seems insanely complicated to
me, though: which user is supposed to deal with such complications?
It's sort of historic ... with plugin support for GNU ld we can probably
drop this flag for 4.7 (eventually I'd even like to enforce the use
of the plugin all the time or disable LTO, just for the sake of reducing
the testing and bugreporting matrix ...).
I just noticed the above with the LTO setup of our SPEC testers
which are using somewhat old system tools.
Here's the patch I came up with. It is on top of the previous one, so
if we want to backport to 4.6 later, both are necessary.
It also fixes a typo in the in_tree_ld case, which can never have worked.
Tested by i386-pc-solaris2.11 bootstraps with either Sun ld or gld 2.21,
and by configuring with Sun ld --with-plugin-ld=gld-2.21 and obvserving
HAVE_LTO_PLUGIN being set to 1.
Ok for mainline now and 4.6 after some soak time?
Thanks.
Rainer
2011-03-19 Rainer Orth<ro@CeBiTec.Uni-Bielefeld.DE>
* configure.ac (gcc_cv_lto_plugin): Fix typo.
Allow -fuse-linker-plugin for non-default plugin linker.
* configure: Regenerate.
diff -r 916a52719d80 gcc/configure.ac
--- a/gcc/configure.ac Sat Mar 19 08:54:19 2011 +0100
+++ b/gcc/configure.ac Sun Mar 20 13:37:38 2011 +0100
@@ -3192,14 +3192,14 @@
AC_MSG_CHECKING(linker plugin support)
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 $in_tree_ld = yes -a x"$ORIGINAL_PLUGIN_LD_FOR_TARGET" = x"$gcc_cv_ld"; then
if test "$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
+ elif test x"$ORIGINAL_PLUGIN_LD_FOR_TARGET" = x"$gcc_cv_ld"&& 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 "$ld_vers_minor" -ge 21; then
gcc_cv_lto_plugin=2
@@ -3207,6 +3207,10 @@
elif test "$ld_is_gold" = yes -a "$ld_vers_major" -eq 2 -a "$ld_vers_minor" -eq 20; then
gcc_cv_lto_plugin=1
fi
+ elif test x"$ORIGINAL_PLUGIN_LD_FOR_TARGET" != x"$gcc_cv_ld"; then
+ # Allow -fuse-linker-plugin if plugin linker differs from
+ # default/specified linker.
+ gcc_cv_lto_plugin=1
fi
fi
AC_DEFINE_UNQUOTED(HAVE_LTO_PLUGIN, $gcc_cv_lto_plugin,