[Bug c++/57102] [4.9 Regression] ICE: SIGSEGV in fndecl_declared_return_type with -fcompare-debug

["ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57102

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-05-04
     Ever Confirmed|0                           |1

--- Comment #1 from Uros Bizjak <ubizjak at gmail dot com> 2013-05-04 18:48:32 UTC ---
Confirmed, the segfault can be triggered with:

~/gcc-build/gcc/cc1plus -O2 -std=gnu++11 -fno-inline -fdump-final-insns=aaa

The important part is "-fdump-final-insns=...".

...
Performing interprocedural optimizations
 <*free_lang_data> <visibility> <early_local_cleanups> <*free_inline_summary>
<whole-program> <profile_estimate> <cp> <inline> <pure-const>
<static-var>Assembling functions:
 constexpr _Tp&& std::forward(typename std::remove_reference<_Tp>::type&) [with
_Tp = <lambda()>; typename std::remove_reference<_Tp>::type = <lambda()>]
constexpr typename std::remove_reference<_Tp>::type&& std::move(_Tp&&) [with
_Tp = <lambda()>&; typename std::remove_reference<_Tp>::type = <lambda()>]
std::_Sp_counted_ptr_inplace<_Tp, _Alloc, _Lp>::_Impl::_Impl(_Alloc) [with _Tp
= std::__future_base::_Task_state<<lambda()>, __gnu_test::SimpleAllocator<int>,
int()>; _Alloc = __gnu_test::SimpleAllocator<int>; __gnu_cxx::_Lock_policy _Lp
= (__gnu_cxx::_Lock_policy)2u] std::function<_Res(_ArgTypes
...)>::function(_Functor) [with _Functor =
std::reference_wrapper<std::_Bind_simple<std::reference_wrapper<<lambda()> >()>
>; <template-parameter-2-2> = void; _Res = int; _ArgTypes = {}]
final.ii:765:61: internal compiler error: Segmentation fault
 packaged_task<int()> p(allocator_arg, a, []() { return 1; });
                                                             ^
0xa94bff crash_signal
        ../../gcc-svn/trunk/gcc/toplev.c:333
0x54160b fndecl_declared_return_type(tree_node*)
        ../../gcc-svn/trunk/gcc/cp/decl.c:14388
0x5f620c dump_function_decl
        ../../gcc-svn/trunk/gcc/cp/error.c:1416
0x5f7b40 decl_as_string(tree_node*, int)
        ../../gcc-svn/trunk/gcc/cp/error.c:2642
0x69f562 cxx_printable_name_internal
        ../../gcc-svn/trunk/gcc/cp/tree.c:1953
0xa95312 announce_function(tree_node*)
        ../../gcc-svn/trunk/gcc/toplev.c:229
0x7c26f6 expand_function
        ../../gcc-svn/trunk/gcc/cgraphunit.c:1610
0x7c44d6 expand_all_functions
        ../../gcc-svn/trunk/gcc/cgraphunit.c:1744
0x7c44d6 compile()
        ../../gcc-svn/trunk/gcc/cgraphunit.c:2042
0x7c4b79 finalize_compilation_unit()
        ../../gcc-svn/trunk/gcc/cgraphunit.c:2119
0x5ea280 cp_write_global_declarations()
        ../../gcc-svn/trunk/gcc/cp/decl2.c:4330
Please submit a full bug report,

It looks that compilation fails during IPO, trying to dump fndecl.

gdb says:

Program received signal SIGSEGV, Segmentation fault.
0x000000000054160b in fndecl_declared_return_type (fn=0x7ffff165ad00) at
../../gcc-svn/trunk/gcc/cp/decl.c:14388
14388               ->x_auto_return_pattern);

(gdb) bt
#0  0x000000000054160b in fndecl_declared_return_type (fn=0x7ffff165ad00) at
../../gcc-svn/trunk/gcc/cp/decl.c:14388
#1  0x00000000005f620d in dump_function_decl (t=0x7ffff165ad00, flags=4) at
../../gcc-svn/trunk/gcc/cp/error.c:1416
#2  0x00000000005f7b41 in decl_as_string (decl=0x7ffff165ad00, flags=4) at
../../gcc-svn/trunk/gcc/cp/error.c:2642
#3  0x000000000069f563 in cxx_printable_name_internal (decl=0x7ffff165ad00,
v=2, translate=<optimized out>) at ../../gcc-svn/trunk/gcc/cp/tree.c:1953
#4  0x0000000000b2a8f9 in dump_function_header (dump_file=0x17cb5a0,
fdecl=0x7ffff165ad00, flags=0) at
../../gcc-svn/trunk/gcc/tree-pretty-print.c:3138
#5  0x000000000087f4b1 in rest_of_clean_state () at
../../gcc-svn/trunk/gcc/final.c:4455
#6  0x00000000009f846f in execute_one_pass (pass=pass@entry=0x1639380
<pass_clean_state>) at ../../gcc-svn/trunk/gcc/passes.c:2337

(gdb) list
14383   fndecl_declared_return_type (tree fn)
14384   {
14385     fn = STRIP_TEMPLATE (fn);
14386     if (FNDECL_USED_AUTO (fn))
14387       return (DECL_STRUCT_FUNCTION (fn)->language
14388               ->x_auto_return_pattern);
14389     else
14390       return TREE_TYPE (TREE_TYPE (fn));
14391   }
14392