[Bug tree-optimization/50767] New: [4.7 Regression] ICE: in refs_may_alias_p_1, at tree-ssa-alias.c:1004 with -O2 -fno-tree-copy-prop -fno-tree-dominator-opts

[zsojka at seznam dot cz]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50767

             Bug #: 50767
           Summary: [4.7 Regression] ICE: in refs_may_alias_p_1, at
                    tree-ssa-alias.c:1004 with -O2 -fno-tree-copy-prop
                    -fno-tree-dominator-opts
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zsojka@seznam.cz
              Host: x86_64-pc-linux-gnu
            Target: x86_64-pc-linux-gnu


Created attachment 25531
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25531
reduced testcase

Compiler output:
$ gcc -O2 -fno-tree-copy-prop -fno-tree-dominator-opts testcase.c 
testcase.c: In function 'foo':
testcase.c:11:6: internal compiler error: in refs_may_alias_p_1, at
tree-ssa-alias.c:1004
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

(gdb) bt
#0  fancy_abort (file=0x128b668 "/mnt/svn/gcc-trunk/gcc/tree-ssa-alias.c",
line=1004, function=0x128b950 "refs_may_alias_p_1")
    at /mnt/svn/gcc-trunk/gcc/diagnostic.c:892
#1  0x0000000000a7ce7a in refs_may_alias_p_1 (ref1=0x7fffffffd5c0,
ref2=0x7fffffffd5f0, tbaa_p=true) at
/mnt/svn/gcc-trunk/gcc/tree-ssa-alias.c:991
#2  0x0000000000a7f477 in refs_may_alias_p (ref1=Unhandled dwarf expression
opcode 0xf3
) at /mnt/svn/gcc-trunk/gcc/tree-ssa-alias.c:1110
#3  0x0000000000b292b4 in find_replaceable_in_bb (map=Unhandled dwarf
expression opcode 0xf3
) at /mnt/svn/gcc-trunk/gcc/tree-ssa-ter.c:651
#4  find_replaceable_exprs (map=Unhandled dwarf expression opcode 0xf3
) at /mnt/svn/gcc-trunk/gcc/tree-ssa-ter.c:718
#5  0x0000000000a3ddbe in remove_ssa_form (sa=0x179f5e0) at
/mnt/svn/gcc-trunk/gcc/tree-outof-ssa.c:923
#6  rewrite_out_of_ssa (sa=0x179f5e0) at
/mnt/svn/gcc-trunk/gcc/tree-outof-ssa.c:1143
#7  0x000000000066c16b in gimple_expand_cfg () at
/mnt/svn/gcc-trunk/gcc/cfgexpand.c:4155
#8  0x00000000008e3c88 in execute_one_pass (pass=0x1792ba0) at
/mnt/svn/gcc-trunk/gcc/passes.c:2064
#9  0x00000000008e3ff5 in execute_pass_list (pass=0x1792ba0) at
/mnt/svn/gcc-trunk/gcc/passes.c:2119
#10 0x0000000000a3b03e in tree_rest_of_compilation (fndecl=0x7ffff5688c00) at
/mnt/svn/gcc-trunk/gcc/tree-optimize.c:420
#11 0x0000000000692e16 in cgraph_expand_function (node=0x7ffff7ed06c0) at
/mnt/svn/gcc-trunk/gcc/cgraphunit.c:1805
#12 0x0000000000694d5c in cgraph_expand_all_functions () at
/mnt/svn/gcc-trunk/gcc/cgraphunit.c:1864
#13 cgraph_optimize () at /mnt/svn/gcc-trunk/gcc/cgraphunit.c:2141
#14 0x000000000069514a in cgraph_finalize_compilation_unit () at
/mnt/svn/gcc-trunk/gcc/cgraphunit.c:1312
#15 0x0000000000577e53 in c_write_global_declarations () at
/mnt/svn/gcc-trunk/gcc/c-decl.c:9940
#16 0x00000000009d9154 in compile_file (argc=15, argv=0x7fffffffda68) at
/mnt/svn/gcc-trunk/gcc/toplev.c:581
#17 do_compile (argc=15, argv=0x7fffffffda68) at
/mnt/svn/gcc-trunk/gcc/toplev.c:1925
#18 toplev_main (argc=15, argv=0x7fffffffda68) at
/mnt/svn/gcc-trunk/gcc/toplev.c:2001
#19 0x00007ffff6178d2d in __libc_start_main () from /lib64/libc.so.6
#20 0x000000000055b8b9 in _start ()

Tested revisions:
r180072 - crash
r179959 - crash
r178498 - OK