[Bug c++/80059] New: [7 Regression] ICE with invalid noexcept for __transaction_atomic

[reichelt at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80059

            Bug ID: 80059
           Summary: [7 Regression] ICE with invalid noexcept for
                    __transaction_atomic
           Product: gcc
           Version: 7.0.1
            Status: UNCONFIRMED
          Keywords: ice-on-invalid-code, trans-mem
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: reichelt at gcc dot gnu.org
  Target Milestone: ---

The following invalid code snippet (compiled with -fgnu-tm) triggers
an ICE on trunk:

=================================================
template<typename> int foo(bool b)
{
  return __transaction_atomic noexcept(b) (0);
}

void bar()
{
  foo<int>(true);
}
=================================================

bug.cc: In function 'int foo(bool)':
bug.cc:3:45: internal compiler error: unexpected expression 'b' of kind
implicit_conv_expr
   return __transaction_atomic noexcept(b) (0);
                                             ^
0x83f890 cxx_eval_constant_expression
        ../../gcc/gcc/cp/constexpr.c:4575
0x842ece cxx_eval_outermost_constant_expr
        ../../gcc/gcc/cp/constexpr.c:4633
0x776f2a build_must_not_throw_expr(tree_node*, tree_node*)
        ../../gcc/gcc/cp/except.c:274
0x7ac6ff build_transaction_expr(unsigned int, tree_node*, int, tree_node*)
        ../../gcc/gcc/cp/semantics.c:8747
0x72628f cp_parser_transaction_expression
        ../../gcc/gcc/cp/parser.c:37871
0x72628f cp_parser_unary_expression
        ../../gcc/gcc/cp/parser.c:7895
0x726c93 cp_parser_cast_expression
        ../../gcc/gcc/cp/parser.c:8780
0x7273e7 cp_parser_binary_expression
        ../../gcc/gcc/cp/parser.c:8881
0x727cb4 cp_parser_assignment_expression
        ../../gcc/gcc/cp/parser.c:9168
0x72b9c8 cp_parser_expression
        ../../gcc/gcc/cp/parser.c:9337
0x719f9a cp_parser_jump_statement
        ../../gcc/gcc/cp/parser.c:12147
0x719f9a cp_parser_statement
        ../../gcc/gcc/cp/parser.c:10581
0x71a84d cp_parser_statement_seq_opt
        ../../gcc/gcc/cp/parser.c:11027
0x71a91f cp_parser_compound_statement
        ../../gcc/gcc/cp/parser.c:10981
0x71aab3 cp_parser_function_body
        ../../gcc/gcc/cp/parser.c:21428
0x71aab3 cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc/gcc/cp/parser.c:21466
0x71b331 cp_parser_function_definition_after_declarator
        ../../gcc/gcc/cp/parser.c:26253
0x71c01d cp_parser_function_definition_from_specifiers_and_declarator
        ../../gcc/gcc/cp/parser.c:26165
0x71c01d cp_parser_init_declarator
        ../../gcc/gcc/cp/parser.c:19155
0x71c5ca cp_parser_single_declaration
        ../../gcc/gcc/cp/parser.c:26711
Please submit a full bug report, [etc.]

This is a recent regression introduced between 2017-03-02 and 2017-03-06.