1 // RUN: %clang_cc1 -Wreturn-type -fsyntax-only -std=c++11 -verify %s 2 3 class A { 4 public: 5 A(const A&); 6 }; 7 8 struct S { 9 int i; 10 double d; 11 12 virtual void B() {} 13 }; 14 15 union U { 16 struct { 17 int i; 18 virtual void B() {} // Can only do this in C++11 19 } t; 20 }; 21 22 struct S2 { 23 int i; 24 double d; 25 }; 26 27 extern "C" U f3( void ); // expected-warning {{'f3' has C-linkage specified, but returns user-defined type 'U' which is incompatible with C}} 28 extern "C" S f0(void); // expected-warning {{'f0' has C-linkage specified, but returns user-defined type 'S' which is incompatible with C}} 29 extern "C" A f4( void ); // expected-warning {{'f4' has C-linkage specified, but returns user-defined type 'A' which is incompatible with C}} 30 31 // These should all be fine 32 extern "C" S2 f5( void ); 33 extern "C" void f2( A x ); 34 extern "C" void f6( S s ); 35 extern "C" void f7( U u ); 36 extern "C" double f8(void); 37 extern "C" long long f11( void ); 38 extern "C" A *f10( void ); 39 40 extern "C" struct mypodstruct f12(); // expected-warning {{'f12' has C-linkage specified, but returns incomplete type 'struct mypodstruct' which could be incompatible with C}} 41