summaryrefslogtreecommitdiff
path: root/clang/test/Sema/return.c
blob: 77bd3f688ed9e2d90231690c896571af6bebcaa0 (about) (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
// RUN: %clang %s -fsyntax-only -Wignored-qualifiers -Wno-error=return-type -Xclang -verify -fblocks -Wno-unreachable-code -Wno-unused-value

// clang emits the following warning by default.
// With GCC, -pedantic, -Wreturn-type or -Wall are required to produce the 
// following warning.
int t14() {
  return; // expected-warning {{non-void function 't14' should return a value}}
}

void t15() {
  return 1; // expected-warning {{void function 't15' should not return a value}}
}

int unknown();

void test0() {
}

int test1() {
} // expected-warning {{control reaches end of non-void function}}

int test2() {
  a: goto a;
}

int test3() {
  goto a;
  a: ;
} // expected-warning {{control reaches end of non-void function}}


void halt() {
  a: goto a;
}

void halt2() __attribute__((noreturn));

int test4() {
  halt2();
}

int test5() {
  halt2(), (void)1;
}

int test6() {
  1, halt2();
}

int j;
int unknown_nohalt() {
  return j;
}

int test7() {
  unknown();
} // expected-warning {{control reaches end of non-void function}}

int test8() {
  (void)(1 + unknown());
} // expected-warning {{control reaches end of non-void function}}

int halt3() __attribute__((noreturn));

int test9() {
  (void)(halt3() + unknown());
}

int test10() {
  (void)(unknown() || halt3());
} // expected-warning {{control may reach end of non-void function}}

int test11() {
  (void)(unknown() && halt3());
} // expected-warning {{control may reach end of non-void function}}

int test12() {
  (void)(halt3() || unknown());
}

int test13() {
  (void)(halt3() && unknown());
}

int test14() {
  (void)(1 || unknown());
} // expected-warning {{control reaches end of non-void function}}

int test15() {
  (void)(0 || unknown());
} // expected-warning {{control reaches end of non-void function}}

int test16() {
  (void)(0 && unknown());
} // expected-warning {{control reaches end of non-void function}}

int test17() {
  (void)(1 && unknown());
} // expected-warning {{control reaches end of non-void function}}

int test18() {
  (void)(unknown_nohalt() && halt3());
} // expected-warning {{control may reach end of non-void function}}

int test19() {
  (void)(unknown_nohalt() && unknown());
} // expected-warning {{control reaches end of non-void function}}

int test20() {
  int i;
  if (i)
    return 0;
  else if (0)
    return 2;
} // expected-warning {{control may reach end of non-void function}}

int test21() {
  int i;
  if (i)
    return 0;
  else if (1)
    return 2;
}

int test22() {
  int i;
  switch (i) default: ;
} // expected-warning {{control reaches end of non-void function}}

int test23() {
  int i;
  switch (i) {
  case 0:
    return 0;
  case 2:
    return 2;
  }
} // expected-warning {{control may reach end of non-void function}}

int test24() {
  int i;
  switch (i) {
    case 0:
    return 0;
  case 2:
    return 2;
  default:
    return -1;
  }
}

int test25() {
  1 ? halt3() : unknown();
}

int test26() {
  0 ? halt3() : unknown();
} // expected-warning {{control reaches end of non-void function}}

int j;
void (*fptr)() __attribute__((noreturn));
int test27() {
  switch (j) {
  case 1:
    do { } while (1);
    break;
  case 2:
    for (;;) ;
    break;
  case 3:
    for (;1;) ;
    for (;0;) {
      goto done;
    }
    return 1;
  case 4:    
    while (0) { goto done; }
    return 1;
  case 5:
    while (1) { return 1; }
    break;
  case 6:
    fptr();
    break;
  default:
    return 1;
  }
  done: ;
}

// PR4624
void test28() __attribute__((noreturn));
void test28(x) { while (1) { } }

void exit(int);
int test29() {
  exit(1);
}

#include <setjmp.h>
jmp_buf test30_j;
int test30() {
  if (j)
    longjmp(test30_j, 1);
  else
#if defined(_WIN32) || defined(_WIN64) || defined(__CYGWIN__)
    longjmp(test30_j, 2);
#else
    _longjmp(test30_j, 1);
#endif
}

typedef void test31_t(int status);
void test31(test31_t *callback __attribute__((noreturn)));

void test32() {
  ^ (void) { while (1) { } }();
  ^ (void) { if (j) while (1) { } }();
  while (1) { }
}

void test33() {
  if (j) while (1) { }
}

// Test that 'static inline' functions are only analyzed for CFG-based warnings
// when they are used.
static inline int si_has_missing_return() {} // expected-warning{{control reaches end of non-void function}}
static inline int si_has_missing_return_2() {}; // expected-warning{{control reaches end of non-void function}}
static inline int si_forward();
static inline int si_has_missing_return_3(int x) {
  if (x)
   return si_has_missing_return_3(x+1);
} // expected-warning{{control may reach end of non-void function}}

int test_static_inline(int x) {
  si_forward();
  return x ? si_has_missing_return_2() : si_has_missing_return_3(x);
}
static inline int si_forward() {} // expected-warning{{control reaches end of non-void function}}

// Test warnings on ignored qualifiers on return types.
const int ignored_c_quals(); // expected-warning{{'const' type qualifier on return type has no effect}}
const volatile int ignored_cv_quals(); // expected-warning{{'const volatile' type qualifiers on return type have no effect}}
char* const volatile restrict ignored_cvr_quals(); // expected-warning{{'const volatile restrict' type qualifiers on return type have no effect}}

// Test that for switch(enum) that if the switch statement covers all the cases
// that we don't consider that for -Wreturn-type.
enum Cases { C1, C2, C3, C4 };
int test_enum_cases(enum Cases C) {
  switch (C) {
  case C1: return 1;
  case C2: return 2;
  case C4: return 3;
  case C3: return 4;
  }
} // no-warning

// PR12318 - Don't give a may reach end of non-void function warning.
int test34(int x) {
  if (x == 1) {
    return 3;
  } else if ( x == 2 || 1) {
    return 5;
  }
}