When I built gcc 4.3 revision 121818 with

# make bootstrap BOOT_CFLAGS="-O2 -g -pipe"

thes stage 3 compiler was miscompiled:

checking for suffix of object files... configure: error: cannot compute suffix
of object files: cannot compile
See `config.log' for more details.
make[4]: *** [configure-stage3-target-libgcc] Error 1
make[4]: Leaving directory `/export/build/gnu/gcc-test/build-x86_64-linux'
make[3]: *** [stage3-bubble] Error 2
make[3]: Leaving directory `/export/build/gnu/gcc-test/build-x86_64-linux'
make[2]: *** [bootstrap] Error 2

bash-3.1$ cat x.i
int
main ()
{
  return 0;
}
bash-3.1$ ./xgcc -B./ -S x.i -m32
x.i: In function ‘main’:
x.i:5: error: unrecognizable insn:
(insn 26 25 27 (parallel [
            (set (reg/f:SI 7 sp)
                (and:SI (reg/f:SI 7 sp)
                    (const_int -16 [0xfffffffffffffff0])))
            (clobber (reg:CC 17 flags))
        ]) -1 (nil)
    (nil))
x.i:5: internal compiler error: in insn_default_length, at insn-attrtab.c:1238
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.


-- 
           Summary: BOOT_CFLAGS="-O2 -g -mtune=nocona" miscompiled thes
                    stage 3 compiler
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: hjl at lucon dot org
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30770