warn-assignment-condition.cpp source code [clang_source_code/test/SemaCXX/warn-assignment-condition.cpp]

1	// RUN: %clang_cc1 -fsyntax-only -Wparentheses -verify %s
2
3	struct A {
4	int foo();
5	friend A operator+(const A&, const A&);
6	A operator\|=(const A&);
7	operator bool();
8	};
9
10	void test() {
11	int x, *p;
12	A a, b;
13
14	// With scalars.
15	if (x = 7) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
16	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
17	// expected-note{{place parentheses around the assignment to silence this warning}}
18	if ((x = 7)) {}
19	do {
20	} while (x = 7); // expected-warning {{using the result of an assignment as a condition without parentheses}} \
21	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
22	// expected-note{{place parentheses around the assignment to silence this warning}}
23	do {
24	} while ((x = 7));
25	while (x = 7) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
26	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
27	// expected-note{{place parentheses around the assignment to silence this warning}}
28
29	while ((x = 7)) {}
30	for (; x = 7; ) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
31	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
32	// expected-note{{place parentheses around the assignment to silence this warning}}
33	for (; (x = 7); ) {}
34
35	if (p = p) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
36	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
37	// expected-note{{place parentheses around the assignment to silence this warning}}
38	if ((p = p)) {}
39	do {
40	} while (p = p); // expected-warning {{using the result of an assignment as a condition without parentheses}} \
41	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
42	// expected-note{{place parentheses around the assignment to silence this warning}}
43	do {
44	} while ((p = p));
45	while (p = p) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
46	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
47	// expected-note{{place parentheses around the assignment to silence this warning}}
48	while ((p = p)) {}
49	for (; p = p; ) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
50	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
51	// expected-note{{place parentheses around the assignment to silence this warning}}
52	for (; (p = p); ) {}
53
54	// Initializing variables (shouldn't warn).
55	if (int y = x) {}
56	while (int y = x) {}
57	if (A y = a) {}
58	while (A y = a) {}
59
60	// With temporaries.
61	if (x = (b+b).foo()) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
62	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
63	// expected-note{{place parentheses around the assignment to silence this warning}}
64	if ((x = (b+b).foo())) {}
65	do {
66	} while (x = (b+b).foo()); // expected-warning {{using the result of an assignment as a condition without parentheses}} \
67	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
68	// expected-note{{place parentheses around the assignment to silence this warning}}
69	do {
70	} while ((x = (b+b).foo()));
71	while (x = (b+b).foo()) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
72	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
73	// expected-note{{place parentheses around the assignment to silence this warning}}
74	while ((x = (b+b).foo())) {}
75	for (; x = (b+b).foo(); ) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
76	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
77	// expected-note{{place parentheses around the assignment to silence this warning}}
78	for (; (x = (b+b).foo()); ) {}
79
80	// With a user-defined operator.
81	if (a = b + b) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
82	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
83	// expected-note{{place parentheses around the assignment to silence this warning}}
84	if ((a = b + b)) {}
85	do {
86	} while (a = b + b); // expected-warning {{using the result of an assignment as a condition without parentheses}} \
87	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
88	// expected-note{{place parentheses around the assignment to silence this warning}}
89	do {
90	} while ((a = b + b));
91	while (a = b + b) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
92	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
93	// expected-note{{place parentheses around the assignment to silence this warning}}
94	while ((a = b + b)) {}
95	for (; a = b + b; ) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
96	// expected-note{{use '==' to turn this assignment into an equality comparison}} \
97	// expected-note{{place parentheses around the assignment to silence this warning}}
98	for (; (a = b + b); ) {}
99
100	// Compound assignments.
101	if (x \|= 2) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
102	// expected-note{{use '!=' to turn this compound assignment into an inequality comparison}} \
103	// expected-note{{place parentheses around the assignment to silence this warning}}
104
105	if (a \|= b) {} // expected-warning {{using the result of an assignment as a condition without parentheses}} \
106	// expected-note{{use '!=' to turn this compound assignment into an inequality comparison}} \
107	// expected-note{{place parentheses around the assignment to silence this warning}}
108
109	if ((x == 5)) {} // expected-warning {{equality comparison with extraneous parentheses}} \
110	// expected-note {{use '=' to turn this equality comparison into an assignment}} \
111	// expected-note {{remove extraneous parentheses around the comparison to silence this warning}}
112
113	#pragma clang diagnostic push
114	#pragma clang diagnostic ignored "-Wparentheses-equality"
115	if ((x == 5)) {} // no-warning
116	#pragma clang diagnostic pop
117
118	if ((5 == x)) {}
119
120	#define EQ(x,y) ((x) == (y))
121	if (EQ(x, 5)) {}
122	#undef EQ
123	}
124
125	void (*fn)();
126
127	void test2() {
128	if ((fn == test2)) {} // expected-warning {{equality comparison with extraneous parentheses}} \
129	// expected-note {{use '=' to turn this equality comparison into an assignment}} \
130	// expected-note {{remove extraneous parentheses around the comparison to silence this warning}}
131	if ((test2 == fn)) {}
132	}
133
134	namespace rdar9027658 {
135	template <typename T>
136	void f(T t) {
137	if ((t.g == 3)) { } // expected-warning {{equality comparison with extraneous parentheses}} \
138	// expected-note {{use '=' to turn this equality comparison into an assignment}} \
139	// expected-note {{remove extraneous parentheses around the comparison to silence this warning}}
140	}
141
142	struct S { int g; };
143	void test() {
144	f(S()); // expected-note {{in instantiation}}
145	}
146	}
147

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