clang/test/Sema/return-non-void.c

// RUN: %clang_cc1 -Wreturn-type -std=c99 -fsyntax-only -verify=c99 %s
// RUN: %clang_cc1 -Wreturn-type -std=c90 -fsyntax-only -verify=c90 %s

int foo(void) { return; } // c99-error {{non-void function 'foo' should return a value}}
                          // c90-error@-1 {{non-void function 'foo' should return a value}}