[Bug middle-end/50640] [4.7 Regression] FAIL: gfortran.dg/select_type_12.f03 -O (internal compiler error)

["dominiq at lps dot ens.fr" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50640

--- Comment #1 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-10-06 21:38:36 UTC ---
Backtrace

Program received signal SIGSEGV, Segmentation fault.
mark_all_vars_used_1 (tp=<value optimized out>, walk_subtrees=<value optimized
out>, data=<value optimized out>)
    at ../../work/gcc/tree-flow-inline.h:562
562      ann->used = true;
(gdb) bt
#0  mark_all_vars_used_1 (tp=<value optimized out>, walk_subtrees=<value
optimized out>, data=<value optimized out>)
    at ../../work/gcc/tree-flow-inline.h:562
#1  0x00000001009ca496 in walk_tree_1 (tp=<value optimized out>, func=<value
optimized out>, data=<value optimized out>, pset=<value optimized out>, 
    lh=<value optimized out>) at ../../work/gcc/tree.c:10448
#2  0x00000001009cab23 in walk_tree_1 (tp=<value optimized out>, func=<value
optimized out>, data=<value optimized out>, pset=<value optimized out>, 
    lh=<value optimized out>) at ../../work/gcc/tree.c:10526
#3  0x000000010089c1f5 in remove_unused_locals () at
../../work/gcc/tree-ssa-live.c:595
#4  0x00000001006d4afe in execute_function_todo (data=<value optimized out>) at
../../work/gcc/passes.c:1695
#5  0x00000001006d540e in execute_todo (flags=49156) at
../../work/gcc/passes.c:1741
#6  0x00000001006d898a in execute_one_pass (pass=0x100ddb660) at
../../work/gcc/passes.c:2087
#7  0x00000001006d8cdd in execute_pass_list (pass=0x100ddb660) at
../../work/gcc/passes.c:2119
#8  0x00000001006d7d59 in do_per_function_toporder (callback=0x1006d8cc0
<execute_pass_list(opt_pass*)>, data=0x100ddb960)
    at ../../work/gcc/passes.c:1606
#9  0x00000001006d91cd in execute_ipa_pass_list (pass=0x100ddba80) at
../../work/gcc/passes.c:2437
#10 0x00000001003dfba5 in cgraph_optimize () at
../../work/gcc/cgraphunit.c:2011
#11 0x00000001003e015a in cgraph_finalize_compilation_unit () at
../../work/gcc/cgraphunit.c:1312
#12 0x0000000100668b5d in write_global_declarations () at
../../work/gcc/langhooks.c:303
#13 0x0000000100799a20 in toplev_main (argc=3, argv=0x7fff5fbfd998) at
../../work/gcc/toplev.c:581
#14 0x0000000100001a54 in start ()