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// PR c++/96575 // { dg-do compile { target c++17 } } struct S { }; constexpr auto g = [] (S s) { if (__builtin_is_constant_evaluated()) return s; }; template <class T> constexpr auto f (T cb) { return [=] { auto ret = cb({}); return ret; }(); } constexpr auto x = f(g);