141 lines
		
	
	
		
			8.1 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			141 lines
		
	
	
		
			8.1 KiB
		
	
	
	
		
			C++
		
	
	
	
| // RUN: %clang_cc1 -fsyntax-only -verify %s
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| // RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-undefined-compare %s
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| // RUN: %clang_cc1 -fsyntax-only -verify -Wno-tautological-compare -Wtautological-undefined-compare %s
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| // RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-compare %s
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| 
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| void test1(int &x) {
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|   if (x == 1) { }
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|   if (&x == 0) { }
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|   // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|   if (&x != 0) { }
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|   // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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| }
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| 
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| class test2 {
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|   test2() : x(y) {}
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| 
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|   void foo() {
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|     if (this == 0) { }
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|     // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (this != 0) { }
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|     // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|   }
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| 
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|   void bar() {
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|     if (x == 1) { }
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|     if (&x == 0) { }
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&x != 0) { }
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|   }
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| 
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|   int &x;
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|   int y;
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| };
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| 
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| namespace function_return_reference {
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|   int& get_int();
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|   // expected-note@-1 4{{'get_int' returns a reference}}
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|   class B {
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|   public:
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|     static int &stat();
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|     // expected-note@-1 4{{'stat' returns a reference}}
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|     int &get();
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|     // expected-note@-1 8{{'get' returns a reference}}
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|   };
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| 
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|   void test() {
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|     if (&get_int() == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&(get_int()) == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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| 
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|     if (&get_int() != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     if (&(get_int()) != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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| 
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|     if (&B::stat() == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&(B::stat()) == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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| 
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|     if (&B::stat() != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     if (&(B::stat()) != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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| 
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|     B b;
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|     if (&b.get() == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&(b.get()) == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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| 
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|     if (&b.get() != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     if (&(b.get()) != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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| 
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|     B* b_ptr = &b;
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|     if (&b_ptr->get() == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&(b_ptr->get()) == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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| 
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|     if (&b_ptr->get() != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     if (&(b_ptr->get()) != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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| 
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|     int& (B::*m_ptr)() = &B::get;
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|     if (&(b.*m_ptr)() == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&((b.*m_ptr)()) == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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| 
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|     if (&(b.*m_ptr)() != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     if (&((b.*m_ptr)()) != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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| 
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|     int& (*f_ptr)() = &get_int;
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|     if (&(*f_ptr)() == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     if (&((*f_ptr)()) == 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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| 
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|     if (&(*f_ptr)() != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     if (&((*f_ptr)()) != 0) {}
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|   }
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| }
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| 
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| namespace macros {
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|   #define assert(x) if (x) {}
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| 
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|   void test(int &x) {
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|     assert(&x != 0);
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     assert(&x == 0);
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     assert(&x != 0 && "Expecting valid reference");
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|     assert(&x == 0 && "Expecting invalid reference");
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|     // expected-warning@-1{{reference cannot be bound to dereferenced null pointer in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|   }
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| 
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|   class S {
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|     void test() {
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|       assert(this != 0);
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|       // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|       assert(this == 0);
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|       // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|       assert(this != 0 && "Expecting valid reference");
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|       // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true}}
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|       assert(this == 0 && "Expecting invalid reference");
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|       // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false}}
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|     }
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|   };
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| }
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