There is a problem in data dependence analysis that breaks bootstrap with -ftree-vectorize (or any other flag that causes find_data_references_in_loop to be called):
stage1/xgcc -Bstage1/ -B/usr/local/i686-pc-linux-gnu/bin/ -c -g -O2 -msse2 -ftree-vectorize -DIN_GCC -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Wold-style-definition -Wmissing-format-attribute -Werror -fno-common -DHAVE_CONFIG_H -I. -I. -I../../gcc/gcc -I../../gcc/gcc/. -I../../gcc/gcc/../include -I../../gcc/gcc/../libcpp/include -I../../gcc/gcc/../libdecnumber -I../libdecnumber ../../gcc/gcc/recog.c -o recog.o ../../gcc/gcc/recog.c: In function âconstrain_operandsâ: ../../gcc/gcc/recog.c:2273: 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. #0 0x0830b9ba in fold_convert (type=0x0, arg=0x402f57f8) at fold-const.c:1991 #1 0x0861768f in chrec_convert_1 (type=0x0, chrec=0x402f57f8, at_stmt=0x409361b0, use_overflow_semantics=1 '\001') at tree-chrec.c:1268 #2 0x0861738d in chrec_convert (type=0x0, chrec=0x402f57f8, at_stmt=0x409361b0) at tree-chrec.c:1225 #3 0x0862a6ce in create_data_ref (memref=0x40929d98, stmt=0x409361b0, is_read=1 '\001') at tree-data-ref.c:1960 #4 0x08632bc8 in find_data_references_in_loop (loop=0x88b5998, datarefs=0x89e988c) at tree-data-ref.c:4050 #5 0x086338e1 in compute_data_dependences_for_loop (loop=0x88b5998, compute_self_and_read_read_dependences=0 '\0', datarefs=0x89e988c, dependence_relations=0x89e9890) at tree-data-ref.c:4189 #6 0x081c38c2 in vect_analyze_data_refs (loop_vinfo=0x89e9868) at tree-vect-analyze.c:1336 #7 0x081c571d in vect_analyze_loop (loop=0x88b5998) at tree-vect-analyze.c:1999 #8 0x081c0672 in vectorize_loops (loops=0x88f9f18) at tree-vectorizer.c:2040 #9 0x081ac9fb in tree_vectorize () at tree-ssa-loop.c:193 ... (gdb) fr 3 #3 0x0862a6ce in create_data_ref (memref=0x40929d98, stmt=0x409361b0, is_read=1 '\001') at tree-data-ref.c:1960 1960 init_cond = chrec_convert (chrec_type (access_fn), init_cond, stmt); (gdb) call debug_generic_stmt (access_fn) scev_not_known; -- Summary: Bootstrap failure with -msse2 -ftree-vectorize Product: gcc Version: 4.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: bootstrap AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: rakdver at gcc dot gnu dot org GCC host triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27782
