97 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			97 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| // RUN: %clang_cc1 -fsyntax-only -verify -std=c++11 %s
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| 
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| int f() __attribute__((warn_unused_result));
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| 
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| struct S {
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|   void t() const;
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| };
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| S g1() __attribute__((warn_unused_result));
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| S *g2() __attribute__((warn_unused_result));
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| S &g3() __attribute__((warn_unused_result));
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| 
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| void test() {
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|   f(); // expected-warning {{ignoring return value}}
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|   g1(); // expected-warning {{ignoring return value}}
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|   g2(); // expected-warning {{ignoring return value}}
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|   g3(); // expected-warning {{ignoring return value}}
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| 
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|   (void)f();
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|   (void)g1();
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|   (void)g2();
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|   (void)g3();
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| 
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|   if (f() == 0) return;
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| 
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|   g1().t();
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|   g2()->t();
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|   g3().t();
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| 
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|   int i = f();
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|   S s1 = g1();
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|   S *s2 = g2();
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|   S &s3 = g3();
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|   const S &s4 = g1();
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| }
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| 
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| struct X {
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|  int foo() __attribute__((warn_unused_result));
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| };
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| 
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| void bah() {
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|   X x, *x2;
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|   x.foo(); // expected-warning {{ignoring return value}}
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|   x2->foo(); // expected-warning {{ignoring return value}}
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| }
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| 
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| namespace warn_unused_CXX11 {
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| struct [[clang::warn_unused_result]] Status {
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|   bool ok() const;
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|   Status& operator=(const Status& x);
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|   inline void Update(const Status& new_status) {
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|     if (ok()) {
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|       *this = new_status; //no-warning
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|     }
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|   }
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| };
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| Status DoSomething();
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| Status& DoSomethingElse();
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| Status* DoAnotherThing();
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| Status** DoYetAnotherThing();
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| void lazy() {
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|   Status s = DoSomething();
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|   if (!s.ok()) return;
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|   Status &rs = DoSomethingElse();
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|   if (!rs.ok()) return;
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|   Status *ps = DoAnotherThing();
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|   if (!ps->ok()) return;
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|   Status **pps = DoYetAnotherThing();
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|   if (!(*pps)->ok()) return;
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| 
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|   (void)DoSomething();
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|   (void)DoSomethingElse();
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|   (void)DoAnotherThing();
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|   (void)DoYetAnotherThing();
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| 
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|   DoSomething(); // expected-warning {{ignoring return value}}
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|   DoSomethingElse(); // expected-warning {{ignoring return value}}
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|   DoAnotherThing(); // expected-warning {{ignoring return value}}
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|   DoYetAnotherThing();
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| }
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| }
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| 
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| namespace PR17587 {
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| struct [[clang::warn_unused_result]] Status;
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| 
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| struct Foo {
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|   Status Bar();
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| };
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| 
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| struct Status {};
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| 
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| void Bar() {
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|   Foo f;
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|   f.Bar(); // expected-warning {{ignoring return value}}
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| };
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| 
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| }
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