1 // RUN: %clang %s -fsyntax-only -Wignored-qualifiers -Wreturn-type -Xclang -verify -fblocks -Wno-unreachable-code -Wno-unused-value 2 3 // clang emits the following warning by default. 4 // With GCC, -pedantic, -Wreturn-type or -Wall are required to produce the 5 // following warning. 6 int t14() { 7 return; // expected-warning {{non-void function 't14' should return a value}} 8 } 9 10 void t15() { 11 return 1; // expected-warning {{void function 't15' should not return a value}} 12 } 13 14 int unknown(); 15 16 void test0() { 17 } 18 19 int test1() { 20 } // expected-warning {{control reaches end of non-void function}} 21 22 int test2() { 23 a: goto a; 24 } 25 26 int test3() { 27 goto a; 28 a: ; 29 } // expected-warning {{control reaches end of non-void function}} 30 31 32 void halt() { 33 a: goto a; 34 } 35 36 void halt2() __attribute__((noreturn)); 37 38 int test4() { 39 halt2(); 40 } 41 42 int test5() { 43 halt2(), (void)1; 44 } 45 46 int test6() { 47 1, halt2(); 48 } 49 50 int j; 51 int unknown_nohalt() { 52 return j; 53 } 54 55 int test7() { 56 unknown(); 57 } // expected-warning {{control reaches end of non-void function}} 58 59 int test8() { 60 (void)(1 + unknown()); 61 } // expected-warning {{control reaches end of non-void function}} 62 63 int halt3() __attribute__((noreturn)); 64 65 int test9() { 66 (void)(halt3() + unknown()); 67 } 68 69 int test10() { 70 (void)(unknown() || halt3()); 71 } // expected-warning {{control may reach end of non-void function}} 72 73 int test11() { 74 (void)(unknown() && halt3()); 75 } // expected-warning {{control may reach end of non-void function}} 76 77 int test12() { 78 (void)(halt3() || unknown()); 79 } 80 81 int test13() { 82 (void)(halt3() && unknown()); 83 } 84 85 int test14() { 86 (void)(1 || unknown()); 87 } // expected-warning {{control reaches end of non-void function}} 88 89 int test15() { 90 (void)(0 || unknown()); 91 } // expected-warning {{control reaches end of non-void function}} 92 93 int test16() { 94 (void)(0 && unknown()); 95 } // expected-warning {{control reaches end of non-void function}} 96 97 int test17() { 98 (void)(1 && unknown()); 99 } // expected-warning {{control reaches end of non-void function}} 100 101 int test18() { 102 (void)(unknown_nohalt() && halt3()); 103 } // expected-warning {{control may reach end of non-void function}} 104 105 int test19() { 106 (void)(unknown_nohalt() && unknown()); 107 } // expected-warning {{control reaches end of non-void function}} 108 109 int test20() { 110 int i; 111 if (i) 112 return 0; 113 else if (0) 114 return 2; 115 } // expected-warning {{control may reach end of non-void function}} 116 117 int test21() { 118 int i; 119 if (i) 120 return 0; 121 else if (1) 122 return 2; 123 } 124 125 int test22() { 126 int i; 127 switch (i) default: ; 128 } // expected-warning {{control reaches end of non-void function}} 129 130 int test23() { 131 int i; 132 switch (i) { 133 case 0: 134 return 0; 135 case 2: 136 return 2; 137 } 138 } // expected-warning {{control may reach end of non-void function}} 139 140 int test24() { 141 int i; 142 switch (i) { 143 case 0: 144 return 0; 145 case 2: 146 return 2; 147 default: 148 return -1; 149 } 150 } 151 152 int test25() { 153 1 ? halt3() : unknown(); 154 } 155 156 int test26() { 157 0 ? halt3() : unknown(); 158 } // expected-warning {{control reaches end of non-void function}} 159 160 int j; 161 void (*fptr)() __attribute__((noreturn)); 162 int test27() { 163 switch (j) { 164 case 1: 165 do { } while (1); 166 break; 167 case 2: 168 for (;;) ; 169 break; 170 case 3: 171 for (;1;) ; 172 for (;0;) { 173 goto done; 174 } 175 return 1; 176 case 4: 177 while (0) { goto done; } 178 return 1; 179 case 5: 180 while (1) { return 1; } 181 break; 182 case 6: 183 fptr(); 184 break; 185 default: 186 return 1; 187 } 188 done: ; 189 } 190 191 // PR4624 192 void test28() __attribute__((noreturn)); 193 void test28(x) { while (1) { } } 194 195 void exit(int); 196 int test29() { 197 exit(1); 198 } 199 200 #include <setjmp.h> 201 jmp_buf test30_j; 202 int test30() { 203 if (j) 204 longjmp(test30_j, 1); 205 else 206 #if defined(_WIN32) || defined(_WIN64) || defined(__CYGWIN__) 207 longjmp(test30_j, 2); 208 #else 209 _longjmp(test30_j, 1); 210 #endif 211 } 212 213 typedef void test31_t(int status); 214 void test31(test31_t *callback __attribute__((noreturn))); 215 216 void test32() { 217 ^ (void) { while (1) { } }(); 218 ^ (void) { if (j) while (1) { } }(); 219 while (1) { } 220 } 221 222 void test33() { 223 if (j) while (1) { } 224 } 225 226 // Test that 'static inline' functions are only analyzed for CFG-based warnings 227 // when they are used. 228 static inline int si_has_missing_return() {} // expected-warning{{control reaches end of non-void function}} 229 static inline int si_has_missing_return_2() {}; // expected-warning{{control reaches end of non-void function}} 230 static inline int si_forward(); 231 static inline int si_has_missing_return_3(int x) { 232 if (x) 233 return si_has_missing_return_3(x+1); 234 } // expected-warning{{control may reach end of non-void function}} 235 236 int test_static_inline(int x) { 237 si_forward(); 238 return x ? si_has_missing_return_2() : si_has_missing_return_3(x); 239 } 240 static inline int si_forward() {} // expected-warning{{control reaches end of non-void function}} 241 242 // Test warnings on ignored qualifiers on return types. 243 const int ignored_c_quals(); // expected-warning{{'const' type qualifier on return type has no effect}} 244 const volatile int ignored_cv_quals(); // expected-warning{{'const volatile' type qualifiers on return type have no effect}} 245 char* const volatile restrict ignored_cvr_quals(); // expected-warning{{'const volatile restrict' type qualifiers on return type have no effect}} 246 247 // Test that for switch(enum) that if the switch statement covers all the cases 248 // that we don't consider that for -Wreturn-type. 249 enum Cases { C1, C2, C3, C4 }; 250 int test_enum_cases(enum Cases C) { 251 switch (C) { 252 case C1: return 1; 253 case C2: return 2; 254 case C4: return 3; 255 case C3: return 4; 256 } 257 } // no-warning 258
