Douglas Gregor | f8b6e15 | 2011-10-10 17:38:18 +0000 | [diff] [blame] | 1 | // RUN: %clang_cc1 -fsyntax-only -fcxx-exceptions -verify -Wno-unused -Wunused-comparison %s |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 2 | |
| 3 | struct A { |
| 4 | bool operator==(const A&); |
| 5 | bool operator!=(const A&); |
Stephen Hines | 651f13c | 2014-04-23 16:59:28 -0700 | [diff] [blame] | 6 | bool operator<(const A&); |
| 7 | bool operator>(const A&); |
| 8 | bool operator<=(const A&); |
| 9 | bool operator>=(const A&); |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 10 | A operator|=(const A&); |
| 11 | operator bool(); |
| 12 | }; |
| 13 | |
| 14 | void test() { |
| 15 | int x, *p; |
| 16 | A a, b; |
| 17 | |
| 18 | x == 7; // expected-warning {{equality comparison result unused}} \ |
| 19 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 20 | x != 7; // expected-warning {{inequality comparison result unused}} \ |
| 21 | // expected-note {{use '|=' to turn this inequality comparison into an or-assignment}} |
Stephen Hines | 651f13c | 2014-04-23 16:59:28 -0700 | [diff] [blame] | 22 | x < 7; // expected-warning {{relational comparison result unused}} |
| 23 | x > 7; // expected-warning {{relational comparison result unused}} |
| 24 | x <= 7; // expected-warning {{relational comparison result unused}} |
| 25 | x >= 7; // expected-warning {{relational comparison result unused}} |
| 26 | |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 27 | 7 == x; // expected-warning {{equality comparison result unused}} |
| 28 | p == p; // expected-warning {{equality comparison result unused}} \ |
| 29 | // expected-note {{use '=' to turn this equality comparison into an assignment}} \ |
| 30 | // expected-warning {{self-comparison always evaluates to true}} |
Chandler Carruth | 9b10683 | 2011-08-17 09:49:44 +0000 | [diff] [blame] | 31 | a == a; // expected-warning {{equality comparison result unused}} \ |
| 32 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 33 | a == b; // expected-warning {{equality comparison result unused}} \ |
| 34 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 35 | a != b; // expected-warning {{inequality comparison result unused}} \ |
| 36 | // expected-note {{use '|=' to turn this inequality comparison into an or-assignment}} |
Stephen Hines | 651f13c | 2014-04-23 16:59:28 -0700 | [diff] [blame] | 37 | a < b; // expected-warning {{relational comparison result unused}} |
| 38 | a > b; // expected-warning {{relational comparison result unused}} |
| 39 | a <= b; // expected-warning {{relational comparison result unused}} |
| 40 | a >= b; // expected-warning {{relational comparison result unused}} |
| 41 | |
Chandler Carruth | 9b10683 | 2011-08-17 09:49:44 +0000 | [diff] [blame] | 42 | A() == b; // expected-warning {{equality comparison result unused}} |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 43 | if (42) x == 7; // expected-warning {{equality comparison result unused}} \ |
| 44 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 45 | else if (42) x == 7; // expected-warning {{equality comparison result unused}} \ |
| 46 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 47 | else x == 7; // expected-warning {{equality comparison result unused}} \ |
| 48 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 49 | do x == 7; // expected-warning {{equality comparison result unused}} \ |
| 50 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 51 | while (false); |
| 52 | while (false) x == 7; // expected-warning {{equality comparison result unused}} \ |
| 53 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 54 | for (x == 7; // expected-warning {{equality comparison result unused}} \ |
| 55 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 56 | x == 7; // No warning -- result is used |
| 57 | x == 7) // expected-warning {{equality comparison result unused}} \ |
| 58 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 59 | x == 7; // expected-warning {{equality comparison result unused}} \ |
| 60 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
Chandler Carruth | 5440bfa | 2011-08-18 02:04:29 +0000 | [diff] [blame] | 61 | switch (42) default: x == 7; // expected-warning {{equality comparison result unused}} \ |
| 62 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 63 | switch (42) case 42: x == 7; // expected-warning {{equality comparison result unused}} \ |
| 64 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 65 | switch (42) { |
| 66 | case 1: |
| 67 | case 2: |
| 68 | default: |
| 69 | case 3: |
| 70 | case 4: |
Chandler Carruth | 5440bfa | 2011-08-18 02:04:29 +0000 | [diff] [blame] | 71 | x == 7; // expected-warning {{equality comparison result unused}} \ |
| 72 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 73 | } |
| 74 | |
| 75 | (void)(x == 7); |
| 76 | (void)(p == p); // expected-warning {{self-comparison always evaluates to true}} |
| 77 | { bool b = x == 7; } |
| 78 | |
| 79 | { bool b = ({ x == 7; // expected-warning {{equality comparison result unused}} \ |
| 80 | // expected-note {{use '=' to turn this equality comparison into an assignment}} |
| 81 | x == 7; }); } // no warning on the second, its result is used! |
| 82 | |
| 83 | #define EQ(x,y) (x) == (y) |
| 84 | EQ(x, 5); |
| 85 | #undef EQ |
Stephen Hines | 176edba | 2014-12-01 14:53:08 -0800 | [diff] [blame] | 86 | |
| 87 | (void)sizeof(1 < 2, true); // No warning; unevaluated context. |
Chandler Carruth | ec8058f | 2011-08-17 09:34:37 +0000 | [diff] [blame] | 88 | } |
Douglas Gregor | f8b6e15 | 2011-10-10 17:38:18 +0000 | [diff] [blame] | 89 | |
| 90 | namespace PR10291 { |
| 91 | template<typename T> |
| 92 | class X |
| 93 | { |
| 94 | public: |
| 95 | |
| 96 | X() : i(0) { } |
| 97 | |
| 98 | void foo() |
| 99 | { |
| 100 | throw |
| 101 | i == 0u ? |
| 102 | 5 : 6; |
| 103 | } |
| 104 | |
| 105 | private: |
| 106 | int i; |
| 107 | }; |
| 108 | |
| 109 | X<int> x; |
| 110 | } |
Stephen Hines | 6bcf27b | 2014-05-29 04:14:42 -0700 | [diff] [blame] | 111 | |
| 112 | namespace PR19724 { |
| 113 | class stream { |
| 114 | } cout, cin; |
| 115 | |
| 116 | stream &operator<(stream &s, int); |
| 117 | bool operator<(stream &s, stream &s2); |
| 118 | |
| 119 | void test() { |
| 120 | cout < 5; // no warning, operator returns a reference |
| 121 | cout < cin; // expected-warning {{relational comparison result unused}} |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | namespace PR19791 { |
| 126 | struct S { |
| 127 | void operator!=(int); |
| 128 | int operator==(int); |
| 129 | }; |
| 130 | |
| 131 | void test() { |
| 132 | S s; |
| 133 | s != 1; |
| 134 | s == 1; // expected-warning{{equality comparison result unused}} |
| 135 | // expected-note@-1{{use '=' to turn this equality comparison into an assignment}} |
| 136 | } |
| 137 | } |