[Bug c++/84444] New: ICE with __builtin_launder and cast

["reichelt at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84444

            Bug ID: 84444
           Summary: ICE with __builtin_launder and cast
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: reichelt at gcc dot gnu.org
  Target Milestone: ---

The following (valid?) code snippet (compiled with "-O") triggers an ICE
since GCC 7.1.0:

=================================================
struct A {};

__SIZE_TYPE__ foo(A* p)
{
  return (__SIZE_TYPE__)__builtin_launder(p);
}
=================================================

bug.cc: In function 'long unsigned int foo(A*)':
bug.cc:5:44: internal compiler error: Segmentation fault
   return (__SIZE_TYPE__)__builtin_launder(p);
                                            ^
0xeb0f4f crash_signal
        ../../gcc/gcc/toplev.c:325
0xa7fc1a builtin_mathfn_code(tree_node const*)
        ../../gcc/gcc/builtins.c:7840
0xaf0342 convert_to_integer_1
        ../../gcc/gcc/convert.c:553
0x8702ef ocp_convert(tree_node*, tree_node*, int, int, int)
        ../../gcc/gcc/cp/cvt.c:822
0x9e2987 cp_build_c_cast(tree_node*, tree_node*, int)
        ../../gcc/gcc/cp/typeck.c:7802
0x9e2ada build_c_cast(unsigned int, tree_node*, cp_expr)
        ../../gcc/gcc/cp/typeck.c:7706
0x911421 cp_parser_cast_expression
        ../../gcc/gcc/cp/parser.c:9075
0x91198a cp_parser_binary_expression
        ../../gcc/gcc/cp/parser.c:9187
0x913164 cp_parser_assignment_expression
        ../../gcc/gcc/cp/parser.c:9476
0x913878 cp_parser_expression
        ../../gcc/gcc/cp/parser.c:9645
0x91c01b cp_parser_jump_statement
        ../../gcc/gcc/cp/parser.c:12396
0x91c01b cp_parser_statement
        ../../gcc/gcc/cp/parser.c:10810
0x91cdc0 cp_parser_statement_seq_opt
        ../../gcc/gcc/cp/parser.c:11255
0x91ce97 cp_parser_compound_statement
        ../../gcc/gcc/cp/parser.c:11209
0x933610 cp_parser_function_body
        ../../gcc/gcc/cp/parser.c:21750
0x933610 cp_parser_ctor_initializer_opt_and_function_body
        ../../gcc/gcc/cp/parser.c:21787
0x933ec0 cp_parser_function_definition_after_declarator
        ../../gcc/gcc/cp/parser.c:26688
0x934bd7 cp_parser_function_definition_from_specifiers_and_declarator
        ../../gcc/gcc/cp/parser.c:26604
0x934bd7 cp_parser_init_declarator
        ../../gcc/gcc/cp/parser.c:19476
0x93bc78 cp_parser_simple_declaration
        ../../gcc/gcc/cp/parser.c:13038
Please submit a full bug report, [etc.]