https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62077
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #61 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #60)
> Workaround confirmed for GCC 5 (--enable-stage1-checking=release).
So, what about just use the workaround automatically for the default
--enable-stage1-checking (of course, if somebody uses something explicitly, he
is on his own)?
Like:
--- configure.ac.jj 2015-03-27 18:32:41.000000000 +0100
+++ configure.ac 2015-04-17 13:01:30.117314053 +0200
@@ -3482,7 +3482,19 @@ AC_ARG_ENABLE(stage1-checking,
[choose additional checking for stage1 of the compiler])],
[stage1_checking=--enable-checking=${enable_stage1_checking}],
[if test "x$enable_checking" = xno || test "x$enable_checking" = x; then
- stage1_checking=--enable-checking=yes,types
+ # For --disable-checking or implicit --enable-checking=release, avoid
+ # setting --enable-checking=gc in the default stage1 checking for LTO
+ # bootstraps. See PR62077.
+ stage1_checking=--enable-checking=release,misc,gimple,rtlflag,tree,types
+ case $BUILD_CONFIG in
+ *lto*)
+ if test "x$enable_checking" = x && \
+ test -d ${srcdir}/gcc && \
+ test x"`cat ${srcdir}/gcc/DEV-PHASE`" = xexperimental; then
+ stage1_checking=--enable-checking=yes,types
+ fi;;
+ *) stage1_checking=--enable-checking=yes,types;;
+ esac
else
stage1_checking=--enable-checking=$enable_checking,types
fi])
I've so far successfully bootstrapped GCC 5 branch with
../configure --prefix=/tmp/blah --with-gnu-as --with-gnu-ld
--enable-languages=all,go --disable-multilib --disable-nls --with-arch=haswell
--with-tune=haswell --with-build-config=bootstrap-lto
--enable-stage1-checking=release,misc,gimple,rtlflag,tree,types
so it indeed is the gc checking that breaks the LTO bootstrap comparison.
release,misc,gimple,rtlflag,tree,types I believe enables everything yes,types
enables, except for gc checking.
