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