https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99546
--- Comment #4 from 康桓瑋 <hewillk at gmail dot com> --- same form, but this will trigger ICE: ==== struct S{ constexpr static auto s = requires { []; }; }; ==== <source>:1:8: internal compiler error: tree check: expected class 'type', have 'exceptional' (error_mark) in override_type_for_decl_p, at dwarf2out.c:23786 1 | struct S{ | ^ 0x1cfa229 internal_error(char const*, ...) ???:0 0x67b5e5 tree_class_check_failed(tree_node const*, tree_code_class, char const*, int, char const*) ???:0 0xf3666f rest_of_type_compilation(tree_node*, int) ???:0 0x70c969 finish_struct_1(tree_node*) ???:0 0x70e754 finish_struct(tree_node*, tree_node*) ???:0 0x8e121d c_parse_file() ???:0 0xa5f812 c_common_parse_file() ???:0 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions.