#define MOZ_NON_TEMPORARY_CLASS __attribute__((annotate("moz_non_temporary_class"))) #define MOZ_STACK_CLASS __attribute__((annotate("moz_stack_class"))) class MOZ_NON_TEMPORARY_CLASS MOZ_STACK_CLASS TestClass {}; TestClass foo; // expected-error {{variable of type 'TestClass' only valid on the stack}} expected-note {{value incorrectly allocated in a global variable}} TestClass f() { TestClass bar; return bar; } void gobbleref(const TestClass&) { } void g() { gobbleref(f()); // expected-error {{variable of type 'TestClass' is not valid in a temporary}} expected-note {{value incorrectly allocated in a temporary}} }