[Bug bootstrap/27782] New: Bootstrap failure with -msse2 -ftree-vectorize

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

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