[Bug tree-optimization/16690] New: Segfault in verify_dominators

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

gcc version 3.5-tree-ssa-lno 20040719 (merged 20040718)

% cat /tmp/min1.c         
struct GList {
    struct GList *next;
};

void composite(struct GList *tmp, struct GList *frames,
               int need_recomposite, int composited)
{
    if (need_recomposite) {
        while (tmp) {
            if (composited)
                break;
            tmp = tmp->next;
        }
        if (tmp == 0)
            tmp = frames;
        while (tmp)
            tmp = tmp->next;
    }
}

% gdb ./gcc/cc1  
GNU gdb 6.1-debian
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "alpha-linux"...Using host libthread_db library
"/lib/libthread_db.so.1".

(gdb) r -O /tmp/min1.c         
Starting program: /src/gcc-lno-2004.07.19/build/gcc/cc1 -O /tmp/min1.c
 composite

Program received signal SIGSEGV, Segmentation fault.
0x000000012018fc10 in verify_dominators (dir=CDI_DOMINATORS)
    at ../../gcc/dominance.c:822
822               error ("dominator of %d should be %d, not %d",
(gdb) bt
#0  0x000000012018fc10 in verify_dominators (dir=CDI_DOMINATORS)
    at ../../gcc/dominance.c:822
#1  0x0000000120082410 in tree_verify_flow_info () at ../../gcc/tree-cfg.c:3813
#2  0x000000012035fed8 in verify_flow_info () at ../../gcc/cfghooks.c:210
#3  0x000000012007d028 in cleanup_tree_cfg () at ../../gcc/tree-cfg.c:748
#4  0x0000000120186cb4 in copy_loop_headers ()
    at ../../gcc/tree-ssa-loop-ch.c:219
#5  0x0000000120093524 in execute_pass_list (pass=0x1204f5970)
    at ../../gcc/tree-optimize.c:464
#6  0x0000000120093584 in execute_pass_list (pass=0x1204f49a8)
    at ../../gcc/tree-optimize.c:490
#7  0x0000000120093788 in tree_rest_of_compilation (fndecl=0x2000030c380, 
    nested_p=0 '\0') at ../../gcc/tree-optimize.c:565
#8  0x000000012001f4dc in c_expand_body (fndecl=0x2000030c380)
    at ../../gcc/c-decl.c:6365
#9  0x0000000120388878 in cgraph_expand_function (node=0x2000030cb60)
    at ../../gcc/cgraphunit.c:797
#10 0x0000000120388a1c in cgraph_assemble_pending_functions ()
    at ../../gcc/cgraphunit.c:296
#11 0x00000001203891c4 in cgraph_finalize_function (decl=0x2000030c380, 
    nested=0 '\0') at ../../gcc/cgraphunit.c:377
#12 0x000000012001f730 in c_finalize (fndecl=0x2000030c380)
    at ../../gcc/c-decl.c:6235
#13 0x000000012001fb50 in finish_function () at ../../gcc/c-decl.c:6337
#14 0x0000000120003cb8 in yyparse () at c-parse.y:366
#15 0x0000000120009a8c in c_parse_file () at c-parse.y:2932
#16 0x0000000120058648 in c_common_parse_file (set_yydebug=Variable set_yydebug"
is not available.
)
    at ../../gcc/c-opts.c:1086
#17 0x000000012032fd18 in toplev_main (argc=Variable "argc" is not available.
) at ../../gcc/toplev.c:981
#18 0x00000001200702a8 in main (argc=Variable "argc" is not available.
) at ../../gcc/main.c:35

-- 
           Summary: Segfault in verify_dominators
           Product: gcc
           Version: lno
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: falk at debian dot org
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: alphaev68-unknown-linux-gnu
  GCC host triplet: alphaev68-unknown-linux-gnu
GCC target triplet: alphaev68-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16690