https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65970
Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2015-08-29
CC| |trippels at gcc dot gnu.org
Ever confirmed|0 |1
--- Comment #1 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Confirmed. Loops in:
3014 static tree
3015 cxx_eval_loop_expr (const constexpr_ctx *ctx, tree t,
3016 bool *non_constant_p, bool *overflow_p,
3017 tree *jump_target)
3018 {
3019 tree body = TREE_OPERAND (t, 0);
3020 while (true)
3021 {
3022 cxx_eval_statement_list (ctx, body,
3023 non_constant_p, overflow_p, jump_target);
3024 if (returns (jump_target) || breaks (jump_target) ||
*non_constant_p)
3025 break;
3026 }
3027 if (breaks (jump_target))
3028 *jump_target = NULL_TREE;
3029 return NULL_TREE;
3030 }
A variant ICEs:
markus@x4 tmp % cat const.ii
constexpr int foo() {
while (true)
;
return 0;
}
int i = foo();
markus@x4 tmp % g++ -std=c++14 -c const.ii
const.ii:7:12: in constexpr expansion of ‘foo()’
const.ii:7:13: internal compiler error: tree check: expected statement_list,
have nop_expr in tsi_start, at tree-iterator.h:42
int i = foo();
^
0xeef92c tree_check_failed(tree_node const*, char const*, int, char const*,
...)
../../gcc/gcc/tree.c:9499
0x59db9a tree_check(tree_node*, char const*, int, char const*, tree_code)
../../gcc/gcc/tree.h:2858
0x59db9a tsi_start
../../gcc/gcc/tree-iterator.h:42
0x7f085f tsi_start
../../gcc/gcc/cp/constexpr.c:2949
0x7f085f cxx_eval_statement_list
../../gcc/gcc/cp/constexpr.c:2980
0x7eacb6 cxx_eval_loop_expr
../../gcc/gcc/cp/constexpr.c:3023
0x7eacb6 cxx_eval_constant_expression
../../gcc/gcc/cp/constexpr.c:3646
0x7f06e6 cxx_eval_statement_list
../../gcc/gcc/cp/constexpr.c:2996
0x7eb3a4 cxx_eval_constant_expression
../../gcc/gcc/cp/constexpr.c:3580
0x7ea3ba cxx_eval_call_expression
../../gcc/gcc/cp/constexpr.c:1379
0x7eb191 cxx_eval_constant_expression
../../gcc/gcc/cp/constexpr.c:3205
0x7f0991 cxx_eval_outermost_constant_expr
../../gcc/gcc/cp/constexpr.c:3740
0x7f2b3f maybe_constant_init(tree_node*, tree_node*)
../../gcc/gcc/cp/constexpr.c:3943
0x67f5dc store_init_value(tree_node*, tree_node*, vec<tree_node*, va_gc,
vl_embed>**, int)
../../gcc/gcc/cp/typeck2.c:826
0x5e83df check_initializer
../../gcc/gcc/cp/decl.c:6089
0x607884 cp_finish_decl(tree_node*, tree_node*, bool, tree_node*, int)
../../gcc/gcc/cp/decl.c:6714
0x704895 cp_parser_init_declarator
../../gcc/gcc/cp/parser.c:17846
0x707155 cp_parser_simple_declaration
../../gcc/gcc/cp/parser.c:11681
0x7008f3 cp_parser_block_declaration
../../gcc/gcc/cp/parser.c:11555
0x70c737 cp_parser_declaration
../../gcc/gcc/cp/parser.c:11452
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.
markus@x4 tmp % clang++ -Wall -Wextra -std=c++14 -c const.ii
const.ii:1:15: error: constexpr function never produces a constant expression
[-Winvalid-constexpr]
constexpr int foo() {
^
const.ii:3:5: note: constexpr evaluation hit maximum step limit; possible
infinite loop?
;
^
1 error generated.
