http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58583
--- Comment #2 from Volker Reichelt <reichelt at gcc dot gnu.org> --- The second testcase is now also wrongly accepted, due to the fix for PR57887. However, the following testcase still crashes with almost the same stacktrace: =========================== template<int> struct A { int i = (A<0>(), 0); }; =========================== bug.cc: In constructor 'constexpr A<0>::A()': bug.cc:1:22: internal compiler error: in tsubst_copy, at cp/pt.c:12863 template<int> struct A ^ 0x5f62a3 tsubst_copy ../../gcc/gcc/cp/pt.c:12863 0x5d35f2 tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool, bool) ../../gcc/gcc/cp/pt.c:15083 0x6d8523 perform_member_init ../../gcc/gcc/cp/init.c:537 0x6d8523 emit_mem_initializers(tree_node*) ../../gcc/gcc/cp/init.c:1096 0x6e310e synthesize_method(tree_node*) ../../gcc/gcc/cp/method.c:799 0x6532f4 mark_used(tree_node*, int) ../../gcc/gcc/cp/decl2.c:4779 0x580359 build_over_call ../../gcc/gcc/cp/call.c:7119 0x57bd35 build_new_method_call_1 ../../gcc/gcc/cp/call.c:7818 0x57bd35 build_new_method_call(tree_node*, tree_node*, vec<tree_node*, va_gc, vl_embed>**, tree_node*, int, tree_node**, int) ../../gcc/gcc/cp/call.c:7888 0x57ce17 build_special_member_call(tree_node*, tree_node*, vec<tree_node*, va_gc, vl_embed>**, tree_node*, int, int) ../../gcc/gcc/cp/call.c:7444 0x6d5697 build_value_init(tree_node*, int) ../../gcc/gcc/cp/init.c:345 0x61ee49 build_functional_cast(tree_node*, tree_node*, int) ../../gcc/gcc/cp/typeck2.c:1858 0x5d364e tsubst_copy_and_build(tree_node*, tree_node*, int, tree_node*, bool, bool) ../../gcc/gcc/cp/pt.c:14053 0x5d77a5 fold_non_dependent_expr_sfinae(tree_node*, int) ../../gcc/gcc/cp/pt.c:5111 0x5d77e9 build_non_dependent_expr(tree_node*) ../../gcc/gcc/cp/pt.c:21234 0x6a93e7 build_x_compound_expr(unsigned int, tree_node*, tree_node*, int) ../../gcc/gcc/cp/typeck.c:6136 0x6847fb cp_parser_expression ../../gcc/gcc/cp/parser.c:8294 0x67bb3f cp_parser_primary_expression ../../gcc/gcc/cp/parser.c:4279 0x67e5da cp_parser_postfix_expression ../../gcc/gcc/cp/parser.c:5969 0x681698 cp_parser_unary_expression ../../gcc/gcc/cp/parser.c:7170 Please submit a full bug report, [etc.]