[Bug bootstrap/20305] New: Miscompilation of libcpp/macro.c at -O1 and higher

["jakub at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

It seems that gcc-4_0-branch GCC (both 20050228 and 20050303) miscompiles
libcpp/macro.c if compiled at -O1 and higher.  stage1 compiler built that
way dies with:
/usr/include/bits/stdio.h: In function printf':
/usr/include/bits/stdio.h:36: error: syntax error before _restrict__'
/usr/include/bits/stdio.h: In function etchar':
/usr/include/bits/stdio.h:43: error: syntax error before _restrict__'
/usr/include/bits/stdio.h: In function etchar_unlocked':
/usr/include/bits/stdio.h:59: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://bugzilla.redhat.com/bugzilla> for instructions.

when compiling crtstuff.c.  If libcpp/macro.c is built at -O0 or built with
GCC 3.3.4 rather than gcc-4_0-branch, it works just fine.

I'll try to locate the problematic routine and distill a testcase.

-- 
           Summary: Miscompilation of libcpp/macro.c at -O1 and higher
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jakub at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org
GCC target triplet: s390x-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20305