https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107222
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Ever confirmed|0 |1 Last reconfirmed| |2022-10-11 Status|UNCONFIRMED |NEW Keywords| |ABI, wrong-code --- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Here is one which shows the issue at link time. This should link and run. One testcase: ``` struct A { int i; }; union Y { A a; }; constexpr Y make_y(const A a) { return {a}; } template<auto> struct q { }; template<auto V> constexpr q<V> make_q() { return {}; } template<auto> void print(); template<> void print<q<(Y){.a={1}}>{}>() { } int main() { constexpr q x = make_q<make_y({1})>(); constexpr q x1 = make_q<(Y){.a={1}}>(); print<x>(); print<x1>(); } ``` Another one: ``` struct A { int i; }; union Y { A a; }; constexpr Y make_y(const A a) { return {a}; } template<auto> struct q { }; template<auto V> constexpr q<V> make_q() { return {}; } void print(q<(Y){.a={1}}> a) { } void print(...); int main() { constexpr q x = make_q<make_y({1})>(); constexpr q x1 = make_q<(Y){.a={1}}>(); print(x); print(x1); } ``` clang mangles both x and x1 the same ...