[Bug c/36596] New: occasional segfault in bitmap_elt_clear_from

["marcus at jet dot franken dot de" <gcc-bugzilla at gcc dot gnu dot org>]

only since some days I get a segfault with this backtrace:

gdb cc1
r -fpreprocessed agfa_cl20.i -dumpbase agfa_cl20.i -mtune=generic -auxbase
agfa_cl20 -g -O2 -Wall -Wmissing-declarations -version -fstack-protector -fPIC
-o /tmp/ccqJyq0F.sQuit
....
Program received signal SIGSEGV, Segmentation fault.
bitmap_elt_clear_from (head=0x10eb670, elt=0x111d360) at
/home/marcus/projects/gcc.trunk/gcc/bitmap.c:260
260       prev = elt->prev;
(gdb) bt
#0  bitmap_elt_clear_from (head=0x10eb670, elt=0x111d360) at
/home/marcus/projects/gcc.trunk/gcc/bitmap.c:260
#1  0x000000000049f766 in bitmap_obstack_free (map=0x10eb670) at
/home/marcus/projects/gcc.trunk/gcc/bitmap.c:296
#2  0x00000000007fa62c in bitmap_set_free (set=0x10e7bd8) at
/home/marcus/projects/gcc.trunk/gcc/tree-ssa-pre.c:621
#3  0x00000000007fa99d in fini_pre () at
/home/marcus/projects/gcc.trunk/gcc/tree-ssa-pre.c:2029
#4  0x0000000000806e68 in execute_pre (do_fre=0 '\0') at
/home/marcus/projects/gcc.trunk/gcc/tree-ssa-pre.c:4062
#5  0x000000000080733b in do_pre () at
/home/marcus/projects/gcc.trunk/gcc/tree-ssa-pre.c:4072
#6  0x000000000065de4a in execute_one_pass (pass=0xfcdd60) at
/home/marcus/projects/gcc.trunk/gcc/passes.c:1292
#7  0x000000000065e085 in execute_pass_list (pass=0xfcdd60) at
/home/marcus/projects/gcc.trunk/gcc/passes.c:1342
#8  0x000000000065e09d in execute_pass_list (pass=0xfcc920) at
/home/marcus/projects/gcc.trunk/gcc/passes.c:1343
#9  0x000000000074cd16 in tree_rest_of_compilation (fndecl=0x2b60b418d000)
    at /home/marcus/projects/gcc.trunk/gcc/tree-optimize.c:425
#10 0x00000000008fbe12 in cgraph_expand_function (node=0x2b60b403df00)
    at /home/marcus/projects/gcc.trunk/gcc/cgraphunit.c:1158
#11 0x00000000008fe884 in cgraph_optimize () at
/home/marcus/projects/gcc.trunk/gcc/cgraphunit.c:1221
#12 0x0000000000416b82 in c_write_global_declarations () at
/home/marcus/projects/gcc.trunk/gcc/c-decl.c:8066
#13 0x00000000006e3117 in toplev_main (argc=<value optimized out>, argv=<value
optimized out>)
    at /home/marcus/projects/gcc.trunk/gcc/toplev.c:976
#14 0x00002b60b3a3cb54 in __libc_start_main () from /lib64/libc.so.6
#15 0x00000000004040f9 in _start ()


-- 
           Summary: occasional segfault in bitmap_elt_clear_from
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: marcus at jet dot franken dot de
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36596