1 // RUN: %clang_cc1 -triple x86_64-apple-darwin -fsyntax-only -pedantic -verify -Wsign-compare %s -Wno-unreachable-code
2 
3 int test(char *C) { // nothing here should warn.
4   return C != ((void*)0);
5   return C != (void*)0;
6   return C != 0;
7   return C != 1;  // expected-warning {{comparison between pointer and integer ('char *' and 'int')}}
8 }
9 
10 int ints(long a, unsigned long b) {
11   enum EnumA {A};
12   enum EnumB {B};
13   enum EnumC {C = 0x10000};
14   return
15          // (a,b)
16          (a == (unsigned long) b) +  // expected-warning {{comparison of integers of different signs}}
17          (a == (unsigned int) b) +
18          (a == (unsigned short) b) +
19          (a == (unsigned char) b) +
20          ((long) a == b) +  // expected-warning {{comparison of integers of different signs}}
21          ((int) a == b) +  // expected-warning {{comparison of integers of different signs}}
22          ((short) a == b) +  // expected-warning {{comparison of integers of different signs}}
23          ((signed char) a == b) +  // expected-warning {{comparison of integers of different signs}}
24          ((long) a == (unsigned long) b) +  // expected-warning {{comparison of integers of different signs}}
25          ((int) a == (unsigned int) b) +  // expected-warning {{comparison of integers of different signs}}
26          ((short) a == (unsigned short) b) +
27          ((signed char) a == (unsigned char) b) +
28          (a < (unsigned long) b) +  // expected-warning {{comparison of integers of different signs}}
29          (a < (unsigned int) b) +
30          (a < (unsigned short) b) +
31          (a < (unsigned char) b) +
32          ((long) a < b) +  // expected-warning {{comparison of integers of different signs}}
33          ((int) a < b) +  // expected-warning {{comparison of integers of different signs}}
34          ((short) a < b) +  // expected-warning {{comparison of integers of different signs}}
35          ((signed char) a < b) +  // expected-warning {{comparison of integers of different signs}}
36          ((long) a < (unsigned long) b) +  // expected-warning {{comparison of integers of different signs}}
37          ((int) a < (unsigned int) b) +  // expected-warning {{comparison of integers of different signs}}
38          ((short) a < (unsigned short) b) +
39          ((signed char) a < (unsigned char) b) +
40 
41          // (A,b)
42          (A == (unsigned long) b) +
43          (A == (unsigned int) b) +
44          (A == (unsigned short) b) +
45          (A == (unsigned char) b) +
46          ((long) A == b) +
47          ((int) A == b) +
48          ((short) A == b) +
49          ((signed char) A == b) +
50          ((long) A == (unsigned long) b) +
51          ((int) A == (unsigned int) b) +
52          ((short) A == (unsigned short) b) +
53          ((signed char) A == (unsigned char) b) +
54          (A < (unsigned long) b) +
55          (A < (unsigned int) b) +
56          (A < (unsigned short) b) +
57          (A < (unsigned char) b) +
58          ((long) A < b) +
59          ((int) A < b) +
60          ((short) A < b) +
61          ((signed char) A < b) +
62          ((long) A < (unsigned long) b) +
63          ((int) A < (unsigned int) b) +
64          ((short) A < (unsigned short) b) +
65          ((signed char) A < (unsigned char) b) +
66 
67          // (a,B)
68          (a == (unsigned long) B) +
69          (a == (unsigned int) B) +
70          (a == (unsigned short) B) +
71          (a == (unsigned char) B) +
72          ((long) a == B) +
73          ((int) a == B) +
74          ((short) a == B) +
75          ((signed char) a == B) +
76          ((long) a == (unsigned long) B) +
77          ((int) a == (unsigned int) B) +
78          ((short) a == (unsigned short) B) +
79          ((signed char) a == (unsigned char) B) +
80          (a < (unsigned long) B) +  // expected-warning {{comparison of integers of different signs}}
81          (a < (unsigned int) B) +
82          (a < (unsigned short) B) +
83          (a < (unsigned char) B) +
84          ((long) a < B) +
85          ((int) a < B) +
86          ((short) a < B) +
87          ((signed char) a < B) +
88          ((long) a < (unsigned long) B) +  // expected-warning {{comparison of integers of different signs}}
89          ((int) a < (unsigned int) B) +  // expected-warning {{comparison of integers of different signs}}
90          ((short) a < (unsigned short) B) +
91          ((signed char) a < (unsigned char) B) +
92 
93          // (C,b)
94          (C == (unsigned long) b) +
95          (C == (unsigned int) b) +
96          (C == (unsigned short) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned short' is always false}}
97          (C == (unsigned char) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned char' is always false}}
98          ((long) C == b) +
99          ((int) C == b) +
100          ((short) C == b) +
101          ((signed char) C == b) +
102          ((long) C == (unsigned long) b) +
103          ((int) C == (unsigned int) b) +
104          ((short) C == (unsigned short) b) +
105          ((signed char) C == (unsigned char) b) +
106          (C < (unsigned long) b) +
107          (C < (unsigned int) b) +
108          (C < (unsigned short) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned short' is always false}}
109          (C < (unsigned char) b) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'unsigned char' is always false}}
110          ((long) C < b) +
111          ((int) C < b) +
112          ((short) C < b) +
113          ((signed char) C < b) +
114          ((long) C < (unsigned long) b) +
115          ((int) C < (unsigned int) b) +
116          ((short) C < (unsigned short) b) +
117          ((signed char) C < (unsigned char) b) +
118 
119          // (a,C)
120          (a == (unsigned long) C) +
121          (a == (unsigned int) C) +
122          (a == (unsigned short) C) +
123          (a == (unsigned char) C) +
124          ((long) a == C) +
125          ((int) a == C) +
126          ((short) a == C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'short' is always false}}
127          ((signed char) a == C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'signed char' is always false}}
128          ((long) a == (unsigned long) C) +
129          ((int) a == (unsigned int) C) +
130          ((short) a == (unsigned short) C) +
131          ((signed char) a == (unsigned char) C) +
132          (a < (unsigned long) C) +  // expected-warning {{comparison of integers of different signs}}
133          (a < (unsigned int) C) +
134          (a < (unsigned short) C) +
135          (a < (unsigned char) C) +
136          ((long) a < C) +
137          ((int) a < C) +
138          ((short) a < C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'short' is always true}}
139          ((signed char) a < C) + // expected-warning {{comparison of constant 'C' (65536) with expression of type 'signed char' is always true}}
140          ((long) a < (unsigned long) C) +  // expected-warning {{comparison of integers of different signs}}
141          ((int) a < (unsigned int) C) +  // expected-warning {{comparison of integers of different signs}}
142          ((short) a < (unsigned short) C) +
143          ((signed char) a < (unsigned char) C) +
144 
145          // (0x80000,b)
146          (0x80000 == (unsigned long) b) +
147          (0x80000 == (unsigned int) b) +
148          (0x80000 == (unsigned short) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned short' is always false}}
149          (0x80000 == (unsigned char) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned char' is always false}}
150          ((long) 0x80000 == b) +
151          ((int) 0x80000 == b) +
152          ((short) 0x80000 == b) +
153          ((signed char) 0x80000 == b) +
154          ((long) 0x80000 == (unsigned long) b) +
155          ((int) 0x80000 == (unsigned int) b) +
156          ((short) 0x80000 == (unsigned short) b) +
157          ((signed char) 0x80000 == (unsigned char) b) +
158          (0x80000 < (unsigned long) b) +
159          (0x80000 < (unsigned int) b) +
160          (0x80000 < (unsigned short) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned short' is always false}}
161          (0x80000 < (unsigned char) b) + // expected-warning {{comparison of constant 524288 with expression of type 'unsigned char' is always false}}
162          ((long) 0x80000 < b) +
163          ((int) 0x80000 < b) +
164          ((short) 0x80000 < b) +
165          ((signed char) 0x80000 < b) +
166          ((long) 0x80000 < (unsigned long) b) +
167          ((int) 0x80000 < (unsigned int) b) +
168          ((short) 0x80000 < (unsigned short) b) +
169          ((signed char) 0x80000 < (unsigned char) b) +
170 
171          // (a,0x80000)
172          (a == (unsigned long) 0x80000) +
173          (a == (unsigned int) 0x80000) +
174          (a == (unsigned short) 0x80000) +
175          (a == (unsigned char) 0x80000) +
176          ((long) a == 0x80000) +
177          ((int) a == 0x80000) +
178          ((short) a == 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'short' is always false}}
179          ((signed char) a == 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'signed char' is always false}}
180          ((long) a == (unsigned long) 0x80000) +
181          ((int) a == (unsigned int) 0x80000) +
182          ((short) a == (unsigned short) 0x80000) +
183          ((signed char) a == (unsigned char) 0x80000) +
184          (a < (unsigned long) 0x80000) +  // expected-warning {{comparison of integers of different signs}}
185          (a < (unsigned int) 0x80000) +
186          (a < (unsigned short) 0x80000) +
187          (a < (unsigned char) 0x80000) +
188          ((long) a < 0x80000) +
189          ((int) a < 0x80000) +
190          ((short) a < 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'short' is always true}}
191          ((signed char) a < 0x80000) + // expected-warning {{comparison of constant 524288 with expression of type 'signed char' is always true}}
192          ((long) a < (unsigned long) 0x80000) +  // expected-warning {{comparison of integers of different signs}}
193          ((int) a < (unsigned int) 0x80000) +  // expected-warning {{comparison of integers of different signs}}
194          ((short) a < (unsigned short) 0x80000) +
195          ((signed char) a < (unsigned char) 0x80000) +
196 
197          // We should be able to avoid warning about this.
198          (b != (a < 4 ? 1 : 2)) +
199 
200          10
201     ;
202 }
203 
204 int equal(char *a, const char *b) {
205     return a == b;
206 }
207 
208 int arrays(char (*a)[5], char(*b)[10], char(*c)[5]) {
209   int d = (a == c);
210   return a == b; // expected-warning {{comparison of distinct pointer types}}
211 }
212 
213 int pointers(int *a) {
214   return a > 0; // expected-warning {{ordered comparison between pointer and zero ('int *' and 'int') is an extension}}
215   return a > 42; // expected-warning {{ordered comparison between pointer and integer ('int *' and 'int')}}
216   return a > (void *)0; // expected-warning {{comparison of distinct pointer types}}
217 }
218 
219 int function_pointers(int (*a)(int), int (*b)(int), void (*c)(int)) {
220   return a > b; // expected-warning {{ordered comparison of function pointers}}
221   return function_pointers > function_pointers; // expected-warning {{self-comparison always evaluates to false}} expected-warning{{ordered comparison of function pointers}}
222   return a > c; // expected-warning {{comparison of distinct pointer types}}
223   return a == (void *) 0;
224   return a == (void *) 1; // expected-warning {{equality comparison between function pointer and void pointer}}
225 }
226 
227 int void_pointers(void* foo) {
228   return foo == (void*) 0;
229   return foo == (void*) 1;
230 }
231 
232 
233 int test1(int i) {
234   enum en { zero };
235   return i > zero;
236 }
237 
238 // PR5937
239 int test2(int i32) {
240   struct foo {
241     unsigned int u8 : 8;
242     unsigned long long u31 : 31;
243     unsigned long long u32 : 32;
244     unsigned long long u63 : 63;
245     unsigned long long u64 : 64;
246   } *x;
247 
248   if (x->u8 == i32) { // comparison in int32, exact
249     return 0;
250   } else if (x->u31 == i32) { // comparison in int32, exact
251     return 1;
252   } else if (x->u32 == i32) { // expected-warning {{comparison of integers of different signs}}
253     return 2;
254   } else if (x->u63 == i32) { // comparison in uint64, exact because ==
255     return 3;
256   } else if (x->u64 == i32) { // expected-warning {{comparison of integers of different signs}}
257     return 4;
258   } else {
259     return 5;
260   }
261 }
262 
263 // PR5887
264 void test3() {
265   unsigned short x, y;
266   unsigned int z;
267   if ((x > y ? x : y) > z)
268     (void) 0;
269 }
270 
271 // PR5961
272 extern char *ptr4;
273 void test4() {
274   long value;
275   if (value < (unsigned long) &ptr4) // expected-warning {{comparison of integers of different signs}}
276     return;
277 }
278 
279 // PR4807
280 int test5(unsigned int x) {
281   return (x < 0) // expected-warning {{comparison of unsigned expression < 0 is always false}}
282     && (0 > x)   // expected-warning {{comparison of 0 > unsigned expression is always false}}
283     && (x >= 0)  // expected-warning {{comparison of unsigned expression >= 0 is always true}}
284     && (0 <= x); // expected-warning {{comparison of 0 <= unsigned expression is always true}}
285 }
286 
287 int test6(unsigned i, unsigned power) {
288   unsigned x = (i < (1 << power) ? i : 0);
289   return x != 3 ? 1 << power : i;
290 }
291 
292 // <rdar://problem/8414119> enum >= (enum)0 comparison should not generate any warnings
293 enum rdar8414119_Vals { X, Y, Z };
294 #define ZERO 0
295 #define CHECK(x) (x >= X)
296 void rdar8414119_foo(enum rdar8414119_Vals v) {
297   if (CHECK(v)) // no-warning
298    return;
299   if (v >= X) // no-warning
300    return;
301 }
302 int rdar8414119_bar(unsigned x) {
303   return x >= ZERO; // no-warning
304 }
305 #undef ZERO
306 #undef CHECK
307 
308 int rdar8511238() {
309   enum A { A_foo, A_bar };
310   enum A a;
311   if (a < 0) // expected-warning {{comparison of unsigned enum expression < 0 is always false}}
312     return 0;
313   return 20;
314 }
315 
316 // PR10336
317 int test9(int sv, unsigned uv, long slv) {
318   return sv == (uv ^= slv); // expected-warning {{comparison of integers of different signs: 'int' and 'unsigned int'}}
319 }
320 
321 void test10(void) {
322   int si;
323   unsigned int ui;
324   long sl;
325 
326   _Bool b;
327   b = (si == (ui = sl)); // expected-warning {{comparison of integers of different signs: 'int' and 'unsigned int'}}
328   b = (si == (ui = sl&15));
329 }
330 
331 // PR11572
332 struct test11S { unsigned x : 30; };
333 int test11(unsigned y, struct test11S *p) {
334   return y > (p->x >> 24); // no-warning
335 }
336 
337 typedef char one_char[1];
338 typedef char two_chars[2];
339 
340 void test12(unsigned a) {
341   if (0 && -1 > a) { }
342 }
343