1f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith// RUN: %clang_cc1 -std=c++11 -verify %s 2f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith 3f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith// expected-no-diagnostics 4f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithusing size_t = decltype(sizeof(0)); 5f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith 6f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithtemplate<typename T, typename U> 7f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithconstexpr T max(T t, U u) { return t > u ? t : u; } 8f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith 9f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithtemplate<typename T, typename ...Ts> 10f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithconstexpr auto max(T t, Ts ...ts) -> decltype(max(t, max(ts...))) { 11f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith return max(t, max(ts...)); 12f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith} 13f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith 14f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithtemplate<typename...T> struct my_union { 15f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith alignas(T...) char buffer[max(sizeof(T)...)]; 16f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith}; 17f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith 18f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithstruct alignas(8) A { char c; }; 19f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithstruct alignas(4) B { short s; }; 20f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithstruct C { char a[16]; }; 21f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smith 22f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithstatic_assert(sizeof(my_union<A, B, C>) == 16, ""); 23f6565a9f7318b1ca6ea9510003dde7b89696daabRichard Smithstatic_assert(alignof(my_union<A, B, C>) == 8, ""); 24