[Bug c++/79298] New: ICE on invalid C++ code on x86_64-linux-gnu: Segmentation fault

[su at cs dot ucdavis.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79298

            Bug ID: 79298
           Summary: ICE on invalid C++ code on x86_64-linux-gnu:
                    Segmentation fault
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: su at cs dot ucdavis.edu
  Target Milestone: ---

This seems to be a recent regression. 


$ g++-trunk -v  
Using built-in specs.
COLLECT_GCC=g++-trunk
COLLECT_LTO_WRAPPER=/usr/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/7.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto
--prefix=/usr/local/gcc-trunk --disable-bootstrap
Thread model: posix
gcc version 7.0.1 20170130 (experimental) [trunk revision 245020] (GCC) 
$ 
$ g++-trunk -c tmp.cpp
tmp.cpp: In function ‘int foo()’:
tmp.cpp:6:13: error: ‘y’ is not a member of ‘M’
   return M::y;
             ^
tmp.cpp:6:13: internal compiler error: Segmentation fault
0xe13a2f crash_signal
        ../../gcc-source-trunk/gcc/toplev.c:333
0x89192b consider_binding_level
        ../../gcc-source-trunk/gcc/cp/name-lookup.c:4788
0x897a81 suggest_alternative_in_explicit_scope(unsigned int, tree_node*,
tree_node*)
        ../../gcc-source-trunk/gcc/cp/name-lookup.c:4529
0x7871b4 qualified_name_lookup_error(tree_node*, tree_node*, tree_node*,
unsigned int)
        ../../gcc-source-trunk/gcc/cp/error.c:3780
0x843ef8 finish_id_expression(tree_node*, tree_node*, tree_node*, cp_id_kind*,
bool, bool, bool*, bool, bool, bool, bool, char const**, unsigned int)
        ../../gcc-source-trunk/gcc/cp/semantics.c:3461
0x7b0373 cp_parser_primary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:5335
0x7b314e cp_parser_postfix_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:6782
0x7ae3cc cp_parser_unary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8101
0x7bb627 cp_parser_cast_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8778
0x7bbc35 cp_parser_binary_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:8880
0x7bc520 cp_parser_assignment_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9168
0x7befe9 cp_parser_expression
        ../../gcc-source-trunk/gcc/cp/parser.c:9335
0x7d16a3 cp_parser_jump_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:12145
0x7d16a3 cp_parser_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10579
0x7d21cc cp_parser_statement_seq_opt
        ../../gcc-source-trunk/gcc/cp/parser.c:11025
0x7d22bf cp_parser_compound_statement
        ../../gcc-source-trunk/gcc/cp/parser.c:10979
0x7cccaf cp_parser_function_body
        ../../gcc-source-trunk/gcc/cp/parser.c:21431
0x7cccaf cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc-source-trunk/gcc/cp/parser.c:21467
0x7cd591 cp_parser_function_definition_after_declarator
        ../../gcc-source-trunk/gcc/cp/parser.c:26235
0x7ce7c9 cp_parser_function_definition_from_specifiers_and_declarator
        ../../gcc-source-trunk/gcc/cp/parser.c:26147
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
$ 


-----------------------------


namespace N { int x; }
namespace M = N; 

int foo () 
{
  return M::y;
}