The attached testcase (sorry, no time to reduce its size) causes current mainline to segfault:
>gcc -v -O2 -c bug.i Reading specs from /afs/mpa/data/martin/ugcc/lib/gcc/i686-pc-linux-gnu/4.0.0/specs Configured with: /scratch/gcc/configure --quiet --prefix=/afs/mpa/data/martin/ugcc --enable-languages=c++,f95 --with-gmp=/afs/mpa/data/martin/mygmp Thread model: posix gcc version 4.0.0 20040929 (experimental) /afs/mpa/data/martin/ugcc/libexec/gcc/i686-pc-linux-gnu/4.0.0/cc1 -fpreprocessed bug.i -quiet -dumpbase bug.i -mtune=pentiumpro -auxbase bug -O2 -version -o /tmp/ccW802VQ.s GNU C version 4.0.0 20040929 (experimental) (i686-pc-linux-gnu) compiled by GNU C version 4.0.0 20040929 (experimental). GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096 eval.l: In function 'fflex': eval.l:518: internal compiler error: Segmentation fault Please submit a full bug report, with preprocessed source if appropriate. See <URL:http://gcc.gnu.org/bugs.html> for instructions. -- Summary: [4.0.0 regression] [ICE on legal code] gcc segfaults with -O2 Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: martin at mpa-garching dot mpg dot de CC: gcc-bugs at gcc dot gnu dot org,martin at mpa-garching dot mpg dot de GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17723