1 // Force x86-64 because some of our heuristics are actually based
2 // on integer sizes.
3
4 // RUN: %clang_cc1 -triple x86_64-apple-darwin -fsyntax-only -pedantic -verify -Wsign-compare -Wtautological-constant-in-range-compare -std=c++11 %s
5 // RUN: %clang_cc1 -triple x86_64-apple-darwin -fsyntax-only -pedantic -verify -Wsign-compare -Wtype-limits -std=c++11 %s
6
test0(long a,unsigned long b)7 int test0(long a, unsigned long b) {
8 enum EnumA {A};
9 enum EnumB {B};
10 enum EnumC {C = 0x10000};
11 return
12 // (a,b)
13 (a == (unsigned long) b) + // expected-warning {{comparison of integers of different signs}}
14 (a == (unsigned int) b) +
15 (a == (unsigned short) b) +
16 (a == (unsigned char) b) +
17 ((long) a == b) + // expected-warning {{comparison of integers of different signs}}
18 ((int) a == b) + // expected-warning {{comparison of integers of different signs}}
19 ((short) a == b) + // expected-warning {{comparison of integers of different signs}}
20 ((signed char) a == b) + // expected-warning {{comparison of integers of different signs}}
21 ((long) a == (unsigned long) b) + // expected-warning {{comparison of integers of different signs}}
22 ((int) a == (unsigned int) b) + // expected-warning {{comparison of integers of different signs}}
23 ((short) a == (unsigned short) b) +
24 ((signed char) a == (unsigned char) b) +
25 (a < (unsigned long) b) + // expected-warning {{comparison of integers of different signs}}
26 (a < (unsigned int) b) +
27 (a < (unsigned short) b) +
28 (a < (unsigned char) b) +
29 ((long) a < b) + // expected-warning {{comparison of integers of different signs}}
30 ((int) a < b) + // expected-warning {{comparison of integers of different signs}}
31 ((short) a < b) + // expected-warning {{comparison of integers of different signs}}
32 ((signed char) a < b) + // expected-warning {{comparison of integers of different signs}}
33 ((long) a < (unsigned long) b) + // expected-warning {{comparison of integers of different signs}}
34 ((int) a < (unsigned int) b) + // expected-warning {{comparison of integers of different signs}}
35 ((short) a < (unsigned short) b) +
36 ((signed char) a < (unsigned char) b) +
37
38 // (A,b)
39 (A == (unsigned long) b) +
40 (A == (unsigned int) b) +
41 (A == (unsigned short) b) +
42 (A == (unsigned char) b) +
43 ((long) A == b) +
44 ((int) A == b) +
45 ((short) A == b) +
46 ((signed char) A == b) +
47 ((long) A == (unsigned long) b) +
48 ((int) A == (unsigned int) b) +
49 ((short) A == (unsigned short) b) +
50 ((signed char) A == (unsigned char) b) +
51 (A < (unsigned long) b) +
52 (A < (unsigned int) b) +
53 (A < (unsigned short) b) +
54 (A < (unsigned char) b) +
55 ((long) A < b) +
56 ((int) A < b) +
57 ((short) A < b) +
58 ((signed char) A < b) +
59 ((long) A < (unsigned long) b) +
60 ((int) A < (unsigned int) b) +
61 ((short) A < (unsigned short) b) +
62 ((signed char) A < (unsigned char) b) +
63
64 // (a,B)
65 (a == (unsigned long) B) +
66 (a == (unsigned int) B) +
67 (a == (unsigned short) B) +
68 (a == (unsigned char) B) +
69 ((long) a == B) +
70 ((int) a == B) +
71 ((short) a == B) +
72 ((signed char) a == B) +
73 ((long) a == (unsigned long) B) +
74 ((int) a == (unsigned int) B) +
75 ((short) a == (unsigned short) B) +
76 ((signed char) a == (unsigned char) B) +
77 (a < (unsigned long) B) + // expected-warning {{comparison of unsigned expression < 0 is always false}}
78 (a < (unsigned int) B) +
79 (a < (unsigned short) B) +
80 (a < (unsigned char) B) +
81 ((long) a < B) +
82 ((int) a < B) +
83 ((short) a < B) +
84 ((signed char) a < B) +
85 ((long) a < (unsigned long) B) + // expected-warning {{comparison of unsigned expression < 0 is always false}}
86 ((int) a < (unsigned int) B) + // expected-warning {{comparison of unsigned expression < 0 is always false}}
87 ((short) a < (unsigned short) B) +
88 ((signed char) a < (unsigned char) B) +
89
90 // (C,b)
91 (C == (unsigned long) b) +
92 (C == (unsigned int) b) +
93 (C == (unsigned short) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned short' is always false}}
94 (C == (unsigned char) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned char' is always false}}
95 ((long) C == b) +
96 ((int) C == b) +
97 ((short) C == b) +
98 ((signed char) C == b) +
99 ((long) C == (unsigned long) b) +
100 ((int) C == (unsigned int) b) +
101 ((short) C == (unsigned short) b) +
102 ((signed char) C == (unsigned char) b) +
103 (C < (unsigned long) b) +
104 (C < (unsigned int) b) +
105 (C < (unsigned short) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned short' is always false}}
106 (C < (unsigned char) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned char' is always false}}
107 ((long) C < b) +
108 ((int) C < b) +
109 ((short) C < b) +
110 ((signed char) C < b) +
111 ((long) C < (unsigned long) b) +
112 ((int) C < (unsigned int) b) +
113 ((short) C < (unsigned short) b) +
114 ((signed char) C < (unsigned char) b) +
115
116 // (a,C)
117 (a == (unsigned long) C) +
118 (a == (unsigned int) C) +
119 (a == (unsigned short) C) +
120 (a == (unsigned char) C) +
121 ((long) a == C) +
122 ((int) a == C) +
123 ((short) a == C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'short' is always false}}
124 ((signed char) a == C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'signed char' is always false}}
125 ((long) a == (unsigned long) C) +
126 ((int) a == (unsigned int) C) +
127 ((short) a == (unsigned short) C) +
128 ((signed char) a == (unsigned char) C) +
129 (a < (unsigned long) C) + // expected-warning {{comparison of integers of different signs}}
130 (a < (unsigned int) C) +
131 (a < (unsigned short) C) +
132 (a < (unsigned char) C) +
133 ((long) a < C) +
134 ((int) a < C) +
135 ((short) a < C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'short' is always true}}
136 ((signed char) a < C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'signed char' is always true}}
137 ((long) a < (unsigned long) C) + // expected-warning {{comparison of integers of different signs}}
138 ((int) a < (unsigned int) C) + // expected-warning {{comparison of integers of different signs}}
139 ((short) a < (unsigned short) C) +
140 ((signed char) a < (unsigned char) C) +
141
142 // (0x80000,b)
143 (0x80000 == (unsigned long) b) +
144 (0x80000 == (unsigned int) b) +
145 (0x80000 == (unsigned short) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned short' is always false}}
146 (0x80000 == (unsigned char) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned char' is always false}}
147 ((long) 0x80000 == b) +
148 ((int) 0x80000 == b) +
149 ((short) 0x80000 == b) +
150 ((signed char) 0x80000 == b) +
151 ((long) 0x80000 == (unsigned long) b) +
152 ((int) 0x80000 == (unsigned int) b) +
153 ((short) 0x80000 == (unsigned short) b) +
154 ((signed char) 0x80000 == (unsigned char) b) +
155 (0x80000 < (unsigned long) b) +
156 (0x80000 < (unsigned int) b) +
157 (0x80000 < (unsigned short) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned short' is always false}}
158 (0x80000 < (unsigned char) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned char' is always false}}
159 ((long) 0x80000 < b) +
160 ((int) 0x80000 < b) +
161 ((short) 0x80000 < b) +
162 ((signed char) 0x80000 < b) +
163 ((long) 0x80000 < (unsigned long) b) +
164 ((int) 0x80000 < (unsigned int) b) +
165 ((short) 0x80000 < (unsigned short) b) +
166 ((signed char) 0x80000 < (unsigned char) b) +
167
168 // (a,0x80000)
169 (a == (unsigned long) 0x80000) +
170 (a == (unsigned int) 0x80000) +
171 (a == (unsigned short) 0x80000) +
172 (a == (unsigned char) 0x80000) +
173 ((long) a == 0x80000) +
174 ((int) a == 0x80000) +
175 ((short) a == 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'short' is always false}}
176 ((signed char) a == 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'signed char' is always false}}
177 ((long) a == (unsigned long) 0x80000) +
178 ((int) a == (unsigned int) 0x80000) +
179 ((short) a == (unsigned short) 0x80000) +
180 ((signed char) a == (unsigned char) 0x80000) +
181 (a < (unsigned long) 0x80000) + // expected-warning {{comparison of integers of different signs}}
182 (a < (unsigned int) 0x80000) +
183 (a < (unsigned short) 0x80000) +
184 (a < (unsigned char) 0x80000) +
185 ((long) a < 0x80000) +
186 ((int) a < 0x80000) +
187 ((short) a < 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'short' is always true}}
188 ((signed char) a < 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'signed char' is always true}}
189 ((long) a < (unsigned long) 0x80000) + // expected-warning {{comparison of integers of different signs}}
190 ((int) a < (unsigned int) 0x80000) + // expected-warning {{comparison of integers of different signs}}
191 ((short) a < (unsigned short) 0x80000) +
192 ((signed char) a < (unsigned char) 0x80000) +
193
194 10
195 ;
196 }
197
test1(int i)198 int test1(int i) {
199 enum en { zero };
200 return i > zero;
201 }
202
203 enum E { e };
test2(int i,void * vp)204 void test2(int i, void *vp) {
205 if (&i == vp) { } // ok
206 if (test1 == vp) { } // expected-warning{{equality comparison between function pointer and void pointer}}
207 if (test1 == e) { } // expected-error{{comparison between pointer and integer}}
208 if (vp < 0) { } // expected-error {{comparison between pointer and zero}}
209 if (test1 < e) { } // expected-error{{comparison between pointer and integer}}
210 }
211
212 // PR7536
213 static const unsigned int kMax = 0;
pr7536()214 int pr7536() {
215 return (kMax > 0);
216 }
217
218 // -Wsign-compare should not warn when ?: operands have different signedness.
219 // This will be caught by -Wsign-conversion
test3()220 void test3() {
221 unsigned long a;
222 signed long b;
223 (void) (true ? a : b);
224 (void) (true ? (unsigned int)a : (signed int)b);
225 (void) (true ? b : a);
226 (void) (true ? (unsigned char)b : (signed char)a);
227 }
228
229 // Test comparison of short to unsigned. If tautological compare does not
230 // trigger, then the signed comparison warning will.
test4(short s)231 void test4(short s) {
232 // A is max short plus 1. All zero and positive shorts are smaller than it.
233 // All negative shorts are cast towards the max unsigned range. Relation
234 // comparisons are possible, but equality comparisons are tautological.
235 const unsigned A = 32768;
236 void (s < A); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
237 void (s > A); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
238 void (s <= A); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
239 void (s >= A); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
240
241 void (s == A); // expected-warning{{comparison of constant 32768 with expression of type 'short' is always false}}
242 void (s != A); // expected-warning{{comparison of constant 32768 with expression of type 'short' is always true}}
243
244 // When negative one is converted to an unsigned value, it becomes the max
245 // unsigned. Likewise, a negative one short can also be converted to max
246 // unsigned.
247 const unsigned B = -1;
248 void (s < B); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
249 void (s > B); // expected-warning{{comparison 'short' > 4294967295 is always false}}
250 void (s <= B); // expected-warning{{comparison 'short' <= 4294967295 is always true}}
251 void (s >= B); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
252 void (s == B); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
253 void (s != B); // expected-warning{{comparison of integers of different signs: 'short' and 'const unsigned int'}}
254
255 }
256
test5(bool b)257 void test5(bool b) {
258 (void) (b < -1); // expected-warning{{comparison of constant -1 with expression of type 'bool' is always false}}
259 (void) (b > -1); // expected-warning{{comparison of constant -1 with expression of type 'bool' is always true}}
260 (void) (b == -1); // expected-warning{{comparison of constant -1 with expression of type 'bool' is always false}}
261 (void) (b != -1); // expected-warning{{comparison of constant -1 with expression of type 'bool' is always true}}
262 (void) (b <= -1); // expected-warning{{comparison of constant -1 with expression of type 'bool' is always false}}
263 (void) (b >= -1); // expected-warning{{comparison of constant -1 with expression of type 'bool' is always true}}
264
265 (void) (b < -10); // expected-warning{{comparison of constant -10 with expression of type 'bool' is always false}}
266 (void) (b > -10); // expected-warning{{comparison of constant -10 with expression of type 'bool' is always true}}
267 (void) (b == -10); // expected-warning{{comparison of constant -10 with expression of type 'bool' is always false}}
268 (void) (b != -10); // expected-warning{{comparison of constant -10 with expression of type 'bool' is always true}}
269 (void) (b <= -10); // expected-warning{{comparison of constant -10 with expression of type 'bool' is always false}}
270 (void) (b >= -10); // expected-warning{{comparison of constant -10 with expression of type 'bool' is always true}}
271
272 (void) (b < 2); // expected-warning{{comparison of constant 2 with expression of type 'bool' is always true}}
273 (void) (b > 2); // expected-warning{{comparison of constant 2 with expression of type 'bool' is always false}}
274 (void) (b == 2); // expected-warning{{comparison of constant 2 with expression of type 'bool' is always false}}
275 (void) (b != 2); // expected-warning{{comparison of constant 2 with expression of type 'bool' is always true}}
276 (void) (b <= 2); // expected-warning{{comparison of constant 2 with expression of type 'bool' is always true}}
277 (void) (b >= 2); // expected-warning{{comparison of constant 2 with expression of type 'bool' is always false}}
278
279 (void) (b < 10); // expected-warning{{comparison of constant 10 with expression of type 'bool' is always true}}
280 (void) (b > 10); // expected-warning{{comparison of constant 10 with expression of type 'bool' is always false}}
281 (void) (b == 10); // expected-warning{{comparison of constant 10 with expression of type 'bool' is always false}}
282 (void) (b != 10); // expected-warning{{comparison of constant 10 with expression of type 'bool' is always true}}
283 (void) (b <= 10); // expected-warning{{comparison of constant 10 with expression of type 'bool' is always true}}
284 (void) (b >= 10); // expected-warning{{comparison of constant 10 with expression of type 'bool' is always false}}
285 }
286
test6(signed char sc)287 void test6(signed char sc) {
288 (void)(sc < 200); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always true}}
289 (void)(sc > 200); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always false}}
290 (void)(sc <= 200); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always true}}
291 (void)(sc >= 200); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always false}}
292 (void)(sc == 200); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always false}}
293 (void)(sc != 200); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always true}}
294
295 (void)(200 < sc); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always false}}
296 (void)(200 > sc); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always true}}
297 (void)(200 <= sc); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always false}}
298 (void)(200 >= sc); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always true}}
299 (void)(200 == sc); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always false}}
300 (void)(200 != sc); // expected-warning{{comparison of constant 200 with expression of type 'signed char' is always true}}
301 }
302
303 // Test many signedness combinations.
test7(unsigned long other)304 void test7(unsigned long other) {
305 // Common unsigned, other unsigned, constant unsigned
306 (void)((unsigned)other != (unsigned long)(0x1ffffffff)); // expected-warning{{true}}
307 (void)((unsigned)other != (unsigned long)(0xffffffff));
308 (void)((unsigned long)other != (unsigned)(0x1ffffffff));
309 (void)((unsigned long)other != (unsigned)(0xffffffff));
310
311 // Common unsigned, other signed, constant unsigned
312 (void)((int)other != (unsigned long)(0xffffffffffffffff)); // expected-warning{{different signs}}
313 (void)((int)other != (unsigned long)(0x00000000ffffffff)); // expected-warning{{true}}
314 (void)((int)other != (unsigned long)(0x000000000fffffff));
315 (void)((int)other < (unsigned long)(0x00000000ffffffff)); // expected-warning{{different signs}}
316 (void)((int)other == (unsigned)(0x800000000));
317
318 // Common unsigned, other unsigned, constant signed
319 (void)((unsigned long)other != (int)(0xffffffff)); // expected-warning{{different signs}}
320
321 // Common unsigned, other signed, constant signed
322 // Should not be possible as the common type should also be signed.
323
324 // Common signed, other signed, constant signed
325 (void)((int)other != (long)(0xffffffff)); // expected-warning{{true}}
326 (void)((int)other != (long)(0xffffffff00000000)); // expected-warning{{true}}
327 (void)((int)other != (long)(0xfffffff));
328 (void)((int)other != (long)(0xfffffffff0000000));
329
330 // Common signed, other signed, constant unsigned
331 (void)((int)other != (unsigned char)(0xffff));
332 (void)((int)other != (unsigned char)(0xff));
333
334 // Common signed, other unsigned, constant signed
335 (void)((unsigned char)other != (int)(0xff));
336 (void)((unsigned char)other != (int)(0xffff)); // expected-warning{{true}}
337
338 // Common signed, other unsigned, constant unsigned
339 (void)((unsigned char)other != (unsigned short)(0xff));
340 (void)((unsigned char)other != (unsigned short)(0x100)); // expected-warning{{true}}
341 (void)((unsigned short)other != (unsigned char)(0xff));
342 }
343
test8(int x)344 void test8(int x) {
345 enum E {
346 Negative = -1,
347 Positive = 1
348 };
349
350 (void)((E)x == 1);
351 (void)((E)x == -1);
352 }
353
test9(int x)354 void test9(int x) {
355 enum E : int {
356 Positive = 1
357 };
358 (void)((E)x == 1);
359 }
360
361 namespace templates {
362 template<class T> T max();
363
max()364 template<> constexpr int max<int>() { return 2147483647; };
365
366 template<typename T>
less_than_max(short num,T value)367 bool less_than_max(short num, T value) {
368 const T vmax = max<T>();
369 return (vmax >= num); // no warning
370 }
371
372 template<typename T>
less_than_max(short num)373 bool less_than_max(short num) {
374 // This should trigger one warning on the template pattern, and not a
375 // warning per specialization.
376 return num < max<int>(); // expected-warning{{comparison of constant 2147483647 with expression of type 'short' is always true}}
377 }
378
test10(short num,int x)379 void test10(short num, int x) {
380 less_than_max(num, x);
381 less_than_max<int>(num);
382 less_than_max<long>(num);
383 less_than_max<short>(num);
384 }
385
386 template<typename T>
less_than_zero(T num,T value)387 inline bool less_than_zero(T num, T value) {
388 return num < 0; // no warning
389 }
390
391 template<typename T>
less_than_zero(unsigned num)392 inline bool less_than_zero(unsigned num) {
393 // This should trigger one warning on the template pattern, and not a
394 // warning per specialization.
395 return num < 0; // expected-warning{{comparison of unsigned expression < 0 is always false}}
396 }
397
test11(unsigned num)398 void test11(unsigned num) {
399 less_than_zero(num, num);
400 less_than_zero<int>(num);
401 less_than_zero<long>(num);
402 less_than_zero<short>(num);
403 }
404
compare(unsigned k)405 template<unsigned n> bool compare(unsigned k) { return k >= n; }
406
test12()407 void test12() {
408 compare<0>(42);
409 }
410
411 struct A { static int x; };
412 struct B { static int x; };
413 typedef A otherA;
414
415 template <typename T>
testx()416 void testx() {
417 if (A::x == T::x && // no warning
418 A::x == otherA::x) // expected-warning{{self-comparison always evaluates to true}}
419 return;
420 }
421
test13()422 void test13() {
423 testx<A>();
424 testx<B>();
425 }
426 }
427
428 namespace tautological_enum {
429 enum E { a, b, c } e;
430
431 // FIXME: We should warn about constructing this out-of-range numeration value.
432 const E invalid = (E)-1;
433 // ... but we should not warn about comparing against it.
434 bool x = e == invalid;
435
436 // We should not warn about relational comparisons for enumerators, even if
437 // they're tautological.
438 bool y = e >= a && e <= b;
439 const E first_in_range = a;
440 const E last_in_range = b;
441 bool z = e >= first_in_range && e <= last_in_range;
442 }
443