https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122875
--- Comment #1 from eczbek.void at gmail dot com --- This might also be related: https://godbolt.org/z/xxsrz1ozY ``` template<int> constexpr bool x = true; template<int> concept test = [:substitute(^^x, {}):]; ``` ``` <source>:7:37: internal compiler error: in cp_parser_splice_expression, at cp/parser.cc:6166 7 | concept test = [:substitute(^^x, {}):]; | ^~ 0x2933b28 diagnostics::context::diagnostic_impl(rich_location*, diagnostics::metadata const*, diagnostics::option_id, char const*, __va_list_tag (*) [1], diagnostics::kind) ???:0 0x292891b internal_error(char const*, ...) ???:0 0xb1491a fancy_abort(char const*, int, char const*) ???:0 0xd52a73 c_parse_file() ???:0 0xed9bf9 c_common_parse_file() ???:0 ```
