https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105222
--- Comment #1 from 康桓瑋 <hewillk at gmail dot com> --- gcc rejects this valid syntax with source>:2:32: error: expected ':' before '{' token 2 | auto b = requires { true ? [] {} : [] {}; }; | ^~ | : <source>:2:33: error: expected primary-expression before '{' token 2 | auto b = requires { true ? [] {} : [] {}; }; | ^ <source>:2:35: error: expected ';' before ':' token 2 | auto b = requires { true ? [] {} : [] {}; }; | ^~ | ; https://godbolt.org/z/4c3PPb5Pb