| Richard Trieu | f743275 | 2014-06-06 21:39:26 +0000 | [diff] [blame] | 1 | // RUN: %clang_cc1 -fsyntax-only -verify %s |
| 2 | // RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-undefined-compare %s |
| 3 | // RUN: %clang_cc1 -fsyntax-only -verify -Wno-tautological-compare -Wtautological-undefined-compare %s |
| 4 | // RUN: %clang_cc1 -fsyntax-only -verify -Wtautological-compare %s |
| 5 | |
| 6 | void test1(int &x) { |
| 7 | if (x == 1) { } |
| 8 | if (&x == 0) { } |
| 9 | // 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}} |
| 10 | if (&x != 0) { } |
| 11 | // 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}} |
| 12 | } |
| 13 | |
| 14 | class test2 { |
| 15 | test2() : x(y) {} |
| 16 | |
| 17 | void foo() { |
| 18 | if (this == 0) { } |
| 19 | // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false}} |
| 20 | if (this != 0) { } |
| 21 | // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true}} |
| 22 | } |
| 23 | |
| 24 | void bar() { |
| 25 | if (x == 1) { } |
| 26 | if (&x == 0) { } |
| 27 | // 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}} |
| 28 | if (&x != 0) { } |
| 29 | // 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}} |
| 30 | } |
| 31 | |
| 32 | int &x; |
| 33 | int y; |
| 34 | }; |
| Richard Trieu | c1888e0 | 2014-06-28 23:25:37 +0000 | [diff] [blame] | 35 | |
| 36 | namespace function_return_reference { |
| 37 | int& get_int(); |
| 38 | // expected-note@-1 4{{'get_int' returns a reference}} |
| 39 | class B { |
| 40 | public: |
| 41 | static int &stat(); |
| 42 | // expected-note@-1 4{{'stat' returns a reference}} |
| 43 | int &get(); |
| 44 | // expected-note@-1 8{{'get' returns a reference}} |
| 45 | }; |
| 46 | |
| 47 | void test() { |
| 48 | if (&get_int() == 0) {} |
| 49 | // 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}} |
| 50 | if (&(get_int()) == 0) {} |
| 51 | // 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}} |
| 52 | |
| 53 | if (&get_int() != 0) {} |
| 54 | // 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}} |
| 55 | if (&(get_int()) != 0) {} |
| 56 | // 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}} |
| 57 | |
| 58 | if (&B::stat() == 0) {} |
| 59 | // 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}} |
| 60 | if (&(B::stat()) == 0) {} |
| 61 | // 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}} |
| 62 | |
| 63 | if (&B::stat() != 0) {} |
| 64 | // 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}} |
| 65 | if (&(B::stat()) != 0) {} |
| 66 | // 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}} |
| 67 | |
| 68 | B b; |
| 69 | if (&b.get() == 0) {} |
| 70 | // 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}} |
| 71 | if (&(b.get()) == 0) {} |
| 72 | // 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}} |
| 73 | |
| 74 | if (&b.get() != 0) {} |
| 75 | // 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}} |
| 76 | if (&(b.get()) != 0) {} |
| 77 | // 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}} |
| 78 | |
| 79 | B* b_ptr = &b; |
| 80 | if (&b_ptr->get() == 0) {} |
| 81 | // 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}} |
| 82 | if (&(b_ptr->get()) == 0) {} |
| 83 | // 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}} |
| 84 | |
| 85 | if (&b_ptr->get() != 0) {} |
| 86 | // 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}} |
| 87 | if (&(b_ptr->get()) != 0) {} |
| 88 | // 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}} |
| 89 | |
| 90 | int& (B::*m_ptr)() = &B::get; |
| 91 | if (&(b.*m_ptr)() == 0) {} |
| 92 | // 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}} |
| 93 | if (&((b.*m_ptr)()) == 0) {} |
| 94 | // 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}} |
| 95 | |
| 96 | if (&(b.*m_ptr)() != 0) {} |
| 97 | // 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}} |
| 98 | if (&((b.*m_ptr)()) != 0) {} |
| 99 | // 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}} |
| 100 | |
| 101 | int& (*f_ptr)() = &get_int; |
| 102 | if (&(*f_ptr)() == 0) {} |
| 103 | // 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}} |
| 104 | if (&((*f_ptr)()) == 0) {} |
| 105 | // 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}} |
| 106 | |
| 107 | if (&(*f_ptr)() != 0) {} |
| 108 | // 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}} |
| 109 | if (&((*f_ptr)()) != 0) {} |
| 110 | // 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}} |
| 111 | } |
| 112 | } |
| Richard Trieu | 4cbff5c | 2014-08-08 22:41:43 +0000 | [diff] [blame] | 113 | |
| 114 | namespace macros { |
| 115 | #define assert(x) if (x) {} |
| 116 | |
| 117 | void test(int &x) { |
| 118 | assert(&x != 0); |
| 119 | // 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}} |
| 120 | assert(&x == 0); |
| 121 | // 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}} |
| 122 | assert(&x != 0 && "Expecting valid reference"); |
| 123 | // 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}} |
| 124 | assert(&x == 0 && "Expecting invalid reference"); |
| 125 | // 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}} |
| 126 | } |
| 127 | |
| 128 | class S { |
| 129 | void test() { |
| 130 | assert(this != 0); |
| 131 | // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true}} |
| 132 | assert(this == 0); |
| 133 | // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false}} |
| 134 | assert(this != 0 && "Expecting valid reference"); |
| 135 | // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true}} |
| 136 | assert(this == 0 && "Expecting invalid reference"); |
| 137 | // expected-warning@-1{{'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false}} |
| 138 | } |
| 139 | }; |
| 140 | } |