[Bug c++/61833] New: [4.9] ICE in fold_comparison

["ppluzhnikov at google dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61833

            Bug ID: 61833
           Summary: [4.9] ICE in fold_comparison
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ppluzhnikov at google dot com

Created attachment 33134
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33134&action=edit
test case

Google ref: b/16030670

Originally reported against gcc-4.8.

Attached test case causes gcc-4_9-branch (r212536) to ICE like this (but only
with -O2):

gcc-svn-4_9-r212536/bin/g++ -c -std=c++11 t.ii -O2
t.ii: In function âvoid ToSpec()â:
t.ii:158:1: internal compiler error: Segmentation fault
 ToSpec ()
 ^
0xb947ff crash_signal
    ../../gcc/toplev.c:337
0x952096 fold_comparison
    ../../gcc/fold-const.c:9074
0x95b8a7 fold_binary_loc(unsigned int, tree_code, tree_node*, tree_node*,
tree_node*)
    ../../gcc/fold-const.c:12953
0xbca30d cleanup_control_expr_graph
    ../../gcc/tree-cfgcleanup.c:112
0xbca30d cleanup_control_flow_bb
    ../../gcc/tree-cfgcleanup.c:187
0xbca30d cleanup_tree_cfg_bb
    ../../gcc/tree-cfgcleanup.c:630
0xbcbd48 cleanup_tree_cfg_1
    ../../gcc/tree-cfgcleanup.c:675
0xbcbd48 cleanup_tree_cfg_noloop
    ../../gcc/tree-cfgcleanup.c:731
0xbcbd48 cleanup_tree_cfg()
    ../../gcc/tree-cfgcleanup.c:786
0xaea194 execute_function_todo
    ../../gcc/passes.c:1811
0xaeaa83 execute_todo
    ../../gcc/passes.c:1887
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.

Trunk rejects the reduced test case with "definition of std::initializer_list
does not match #include <initializer_list>" due to fixes for PR61723.

Trunk @r212277 does not ICE.