1 // RUN: %clang_analyze_cc1 -analyzer-checker=core,unix.cstring,unix.Malloc,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify -analyzer-config eagerly-assume=false %s
2 // RUN: %clang_analyze_cc1 -DUSE_BUILTINS -analyzer-checker=core,unix.cstring,unix.Malloc,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify -analyzer-config eagerly-assume=false %s
3 // RUN: %clang_analyze_cc1 -DVARIANT -analyzer-checker=core,unix.cstring,unix.Malloc,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify -analyzer-config eagerly-assume=false %s
4 // RUN: %clang_analyze_cc1 -DUSE_BUILTINS -DVARIANT -analyzer-checker=alpha.security.taint,core,unix.cstring,unix.Malloc,alpha.unix.cstring,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify -analyzer-config eagerly-assume=false %s
5 // RUN: %clang_analyze_cc1 -DSUPPRESS_OUT_OF_BOUND -analyzer-checker=core,unix.cstring,unix.Malloc,alpha.unix.cstring.BufferOverlap,alpha.unix.cstring.NotNullTerminated,debug.ExprInspection -analyzer-store=region -Wno-null-dereference -verify -analyzer-config eagerly-assume=false %s
6 
7 //===----------------------------------------------------------------------===
8 // Declarations
9 //===----------------------------------------------------------------------===
10 
11 // Some functions are so similar to each other that they follow the same code
12 // path, such as memcpy and __memcpy_chk, or memcmp and bcmp. If VARIANT is
13 // defined, make sure to use the variants instead to make sure they are still
14 // checked by the analyzer.
15 
16 // Some functions are implemented as builtins. These should be #defined as
17 // BUILTIN(f), which will prepend "__builtin_" if USE_BUILTINS is defined.
18 
19 // Functions that have variants and are also available as builtins should be
20 // declared carefully! See memcpy() for an example.
21 
22 #ifdef USE_BUILTINS
23 # define BUILTIN(f) __builtin_ ## f
24 #else /* USE_BUILTINS */
25 # define BUILTIN(f) f
26 #endif /* USE_BUILTINS */
27 
28 #define NULL 0
29 typedef typeof(sizeof(int)) size_t;
30 
31 void clang_analyzer_eval(int);
32 
33 int scanf(const char *restrict format, ...);
34 void *malloc(size_t);
35 void free(void *);
36 
37 //===----------------------------------------------------------------------===
38 // strlen()
39 //===----------------------------------------------------------------------===
40 
41 #define strlen BUILTIN(strlen)
42 size_t strlen(const char *s);
43 
44 void strlen_constant0() {
45   clang_analyzer_eval(strlen("123") == 3); // expected-warning{{TRUE}}
46 }
47 
48 void strlen_constant1() {
49   const char *a = "123";
50   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}}
51 }
52 
53 void strlen_constant2(char x) {
54   char a[] = "123";
55   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{TRUE}}
56 
57   a[0] = x;
58   clang_analyzer_eval(strlen(a) == 3); // expected-warning{{UNKNOWN}}
59 }
60 
61 size_t strlen_null() {
62   return strlen(0); // expected-warning{{Null pointer argument in call to string length function}}
63 }
64 
65 size_t strlen_fn() {
66   return strlen((char*)&strlen_fn); // expected-warning{{Argument to string length function is the address of the function 'strlen_fn', which is not a null-terminated string}}
67 }
68 
69 size_t strlen_nonloc() {
70 label:
71   return strlen((char*)&&label); // expected-warning{{Argument to string length function is the address of the label 'label', which is not a null-terminated string}}
72 }
73 
74 void strlen_subregion() {
75   struct two_strings { char a[2], b[2]; };
76   extern void use_two_strings(struct two_strings *);
77 
78   struct two_strings z;
79   use_two_strings(&z);
80 
81   size_t a = strlen(z.a);
82   z.b[0] = 5;
83   size_t b = strlen(z.a);
84   if (a == 0)
85     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
86 
87   use_two_strings(&z);
88 
89   size_t c = strlen(z.a);
90   if (a == 0)
91     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
92 }
93 
94 extern void use_string(char *);
95 void strlen_argument(char *x) {
96   size_t a = strlen(x);
97   size_t b = strlen(x);
98   if (a == 0)
99     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
100 
101   use_string(x);
102 
103   size_t c = strlen(x);
104   if (a == 0)
105     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
106 }
107 
108 extern char global_str[];
109 void strlen_global() {
110   size_t a = strlen(global_str);
111   size_t b = strlen(global_str);
112   if (a == 0) {
113     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
114     // Make sure clang_analyzer_eval does not invalidate globals.
115     clang_analyzer_eval(strlen(global_str) == 0); // expected-warning{{TRUE}}
116   }
117 
118   // Call a function with unknown effects, which should invalidate globals.
119   use_string(0);
120 
121   size_t c = strlen(global_str);
122   if (a == 0)
123     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
124 }
125 
126 void strlen_indirect(char *x) {
127   size_t a = strlen(x);
128   char *p = x;
129   char **p2 = &p;
130   size_t b = strlen(x);
131   if (a == 0)
132     clang_analyzer_eval(b == 0); // expected-warning{{TRUE}}
133 
134   extern void use_string_ptr(char*const*);
135   use_string_ptr(p2);
136 
137   size_t c = strlen(x);
138   if (a == 0)
139     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
140 }
141 
142 void strlen_indirect2(char *x) {
143   size_t a = strlen(x);
144   char *p = x;
145   char **p2 = &p;
146   extern void use_string_ptr2(char**);
147   use_string_ptr2(p2);
148 
149   size_t c = strlen(x);
150   if (a == 0)
151     clang_analyzer_eval(c == 0); // expected-warning{{UNKNOWN}}
152 }
153 
154 void strlen_liveness(const char *x) {
155   if (strlen(x) < 5)
156     return;
157   clang_analyzer_eval(strlen(x) < 5); // expected-warning{{FALSE}}
158 }
159 
160 
161 size_t strlenWrapper(const char *str) {
162   return strlen(str);
163 }
164 
165 extern void invalidate(char *s);
166 
167 void testStrlenCallee() {
168   char str[42];
169   invalidate(str);
170   size_t lenBefore = strlenWrapper(str);
171   invalidate(str);
172   size_t lenAfter = strlenWrapper(str);
173   clang_analyzer_eval(lenBefore == lenAfter); // expected-warning{{UNKNOWN}}
174 }
175 
176 
177 //===----------------------------------------------------------------------===
178 // strnlen()
179 //===----------------------------------------------------------------------===
180 
181 size_t strnlen(const char *s, size_t maxlen);
182 
183 void strnlen_constant0() {
184   clang_analyzer_eval(strnlen("123", 10) == 3); // expected-warning{{TRUE}}
185 }
186 
187 void strnlen_constant1() {
188   const char *a = "123";
189   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}}
190 }
191 
192 void strnlen_constant2(char x) {
193   char a[] = "123";
194   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{TRUE}}
195   a[0] = x;
196   clang_analyzer_eval(strnlen(a, 10) == 3); // expected-warning{{UNKNOWN}}
197 }
198 
199 void strnlen_constant4() {
200   clang_analyzer_eval(strnlen("123456", 3) == 3); // expected-warning{{TRUE}}
201 }
202 
203 void strnlen_constant5() {
204   const char *a = "123456";
205   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}}
206 }
207 
208 void strnlen_constant6(char x) {
209   char a[] = "123456";
210   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{TRUE}}
211   a[0] = x;
212   clang_analyzer_eval(strnlen(a, 3) == 3); // expected-warning{{UNKNOWN}}
213 }
214 
215 size_t strnlen_null() {
216   return strnlen(0, 3); // expected-warning{{Null pointer argument in call to string length function}}
217 }
218 
219 size_t strnlen_fn() {
220   return strnlen((char*)&strlen_fn, 3); // expected-warning{{Argument to string length function is the address of the function 'strlen_fn', which is not a null-terminated string}}
221 }
222 
223 size_t strnlen_nonloc() {
224 label:
225   return strnlen((char*)&&label, 3); // expected-warning{{Argument to string length function is the address of the label 'label', which is not a null-terminated string}}
226 }
227 
228 void strnlen_zero() {
229   clang_analyzer_eval(strnlen("abc", 0) == 0); // expected-warning{{TRUE}}
230   clang_analyzer_eval(strnlen(NULL, 0) == 0); // expected-warning{{TRUE}}
231 }
232 
233 size_t strnlen_compound_literal() {
234   // This used to crash because we don't model the string lengths of
235   // compound literals.
236   return strnlen((char[]) { 'a', 'b', 0 }, 1);
237 }
238 
239 size_t strnlen_unknown_limit(float f) {
240   // This used to crash because we don't model the integer values of floats.
241   return strnlen("abc", (int)f);
242 }
243 
244 void strnlen_is_not_strlen(char *x) {
245   clang_analyzer_eval(strnlen(x, 10) == strlen(x)); // expected-warning{{UNKNOWN}}
246 }
247 
248 void strnlen_at_limit(char *x) {
249   size_t len = strnlen(x, 10);
250   clang_analyzer_eval(len <= 10); // expected-warning{{TRUE}}
251   clang_analyzer_eval(len == 10); // expected-warning{{UNKNOWN}}
252   clang_analyzer_eval(len < 10); // expected-warning{{UNKNOWN}}
253 }
254 
255 void strnlen_at_actual(size_t limit) {
256   size_t len = strnlen("abc", limit);
257   clang_analyzer_eval(len <= 3); // expected-warning{{TRUE}}
258   // This is due to eager assertion in strnlen.
259   if (limit == 0) {
260     clang_analyzer_eval(len == 0); // expected-warning{{TRUE}}
261   } else {
262     clang_analyzer_eval(len == 3); // expected-warning{{UNKNOWN}}
263     clang_analyzer_eval(len < 3); // expected-warning{{UNKNOWN}}
264   }
265 }
266 
267 //===----------------------------------------------------------------------===
268 // strcpy()
269 //===----------------------------------------------------------------------===
270 
271 #ifdef VARIANT
272 
273 #define __strcpy_chk BUILTIN(__strcpy_chk)
274 char *__strcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen);
275 
276 #define strcpy(a,b) __strcpy_chk(a,b,(size_t)-1)
277 
278 #else /* VARIANT */
279 
280 #define strcpy BUILTIN(strcpy)
281 char *strcpy(char *restrict s1, const char *restrict s2);
282 
283 #endif /* VARIANT */
284 
285 
286 void strcpy_null_dst(char *x) {
287   strcpy(NULL, x); // expected-warning{{Null pointer argument in call to string copy function}}
288 }
289 
290 void strcpy_null_src(char *x) {
291   strcpy(x, NULL); // expected-warning{{Null pointer argument in call to string copy function}}
292 }
293 
294 void strcpy_fn(char *x) {
295   strcpy(x, (char*)&strcpy_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}}
296 }
297 
298 void strcpy_fn_const(char *x) {
299   strcpy(x, (const char*)&strcpy_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}}
300 }
301 
302 extern int globalInt;
303 void strcpy_effects(char *x, char *y) {
304   char a = x[0];
305   if (globalInt != 42)
306     return;
307 
308   clang_analyzer_eval(strcpy(x, y) == x); // expected-warning{{TRUE}}
309   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}}
310   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
311   clang_analyzer_eval(globalInt == 42); // expected-warning{{TRUE}}
312 }
313 
314 #ifndef SUPPRESS_OUT_OF_BOUND
315 void strcpy_overflow(char *y) {
316   char x[4];
317   if (strlen(y) == 4)
318     strcpy(x, y); // expected-warning{{String copy function overflows destination buffer}}
319 }
320 #endif
321 
322 void strcpy_no_overflow(char *y) {
323   char x[4];
324   if (strlen(y) == 3)
325     strcpy(x, y); // no-warning
326 }
327 
328 //===----------------------------------------------------------------------===
329 // stpcpy()
330 //===----------------------------------------------------------------------===
331 
332 #ifdef VARIANT
333 
334 #define __stpcpy_chk BUILTIN(__stpcpy_chk)
335 char *__stpcpy_chk(char *restrict s1, const char *restrict s2, size_t destlen);
336 
337 #define stpcpy(a,b) __stpcpy_chk(a,b,(size_t)-1)
338 
339 #else /* VARIANT */
340 
341 #define stpcpy BUILTIN(stpcpy)
342 char *stpcpy(char *restrict s1, const char *restrict s2);
343 
344 #endif /* VARIANT */
345 
346 
347 void stpcpy_effect(char *x, char *y) {
348   char a = x[0];
349 
350   clang_analyzer_eval(stpcpy(x, y) == &x[strlen(y)]); // expected-warning{{TRUE}}
351   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{TRUE}}
352   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
353 }
354 
355 #ifndef SUPPRESS_OUT_OF_BOUND
356 void stpcpy_overflow(char *y) {
357   char x[4];
358   if (strlen(y) == 4)
359     stpcpy(x, y); // expected-warning{{String copy function overflows destination buffer}}
360 }
361 #endif
362 
363 void stpcpy_no_overflow(char *y) {
364   char x[4];
365   if (strlen(y) == 3)
366     stpcpy(x, y); // no-warning
367 }
368 
369 //===----------------------------------------------------------------------===
370 // strcat()
371 //===----------------------------------------------------------------------===
372 
373 #ifdef VARIANT
374 
375 #define __strcat_chk BUILTIN(__strcat_chk)
376 char *__strcat_chk(char *restrict s1, const char *restrict s2, size_t destlen);
377 
378 #define strcat(a,b) __strcat_chk(a,b,(size_t)-1)
379 
380 #else /* VARIANT */
381 
382 #define strcat BUILTIN(strcat)
383 char *strcat(char *restrict s1, const char *restrict s2);
384 
385 #endif /* VARIANT */
386 
387 
388 void strcat_null_dst(char *x) {
389   strcat(NULL, x); // expected-warning{{Null pointer argument in call to string copy function}}
390 }
391 
392 void strcat_null_src(char *x) {
393   strcat(x, NULL); // expected-warning{{Null pointer argument in call to string copy function}}
394 }
395 
396 void strcat_fn(char *x) {
397   strcat(x, (char*)&strcat_fn); // expected-warning{{Argument to string copy function is the address of the function 'strcat_fn', which is not a null-terminated string}}
398 }
399 
400 void strcat_effects(char *y) {
401   char x[8] = "123";
402   size_t orig_len = strlen(x);
403   char a = x[0];
404 
405   if (strlen(y) != 4)
406     return;
407 
408   clang_analyzer_eval(strcat(x, y) == x); // expected-warning{{TRUE}}
409   clang_analyzer_eval((int)strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}}
410 }
411 
412 #ifndef SUPPRESS_OUT_OF_BOUND
413 void strcat_overflow_0(char *y) {
414   char x[4] = "12";
415   if (strlen(y) == 4)
416     strcat(x, y); // expected-warning{{String copy function overflows destination buffer}}
417 }
418 
419 void strcat_overflow_1(char *y) {
420   char x[4] = "12";
421   if (strlen(y) == 3)
422     strcat(x, y); // expected-warning{{String copy function overflows destination buffer}}
423 }
424 
425 void strcat_overflow_2(char *y) {
426   char x[4] = "12";
427   if (strlen(y) == 2)
428     strcat(x, y); // expected-warning{{String copy function overflows destination buffer}}
429 }
430 #endif
431 
432 void strcat_no_overflow(char *y) {
433   char x[5] = "12";
434   if (strlen(y) == 2)
435     strcat(x, y); // no-warning
436 }
437 
438 void strcat_symbolic_dst_length(char *dst) {
439 	strcat(dst, "1234");
440   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
441 }
442 
443 void strcat_symbolic_dst_length_taint(char *dst) {
444   scanf("%s", dst); // Taint data.
445   strcat(dst, "1234");
446   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
447 }
448 
449 void strcat_unknown_src_length(char *src, int offset) {
450 	char dst[8] = "1234";
451 	strcat(dst, &src[offset]);
452   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
453 }
454 
455 // There is no strcat_unknown_dst_length because if we can't get a symbolic
456 // length for the "before" strlen, we won't be able to set one for "after".
457 
458 void strcat_too_big(char *dst, char *src) {
459   // We assume this can never actually happen, so we don't get a warning.
460 	if (strlen(dst) != (((size_t)0) - 2))
461 		return;
462 	if (strlen(src) != 2)
463 		return;
464 	strcat(dst, src);
465 }
466 
467 
468 //===----------------------------------------------------------------------===
469 // strncpy()
470 //===----------------------------------------------------------------------===
471 
472 #ifdef VARIANT
473 
474 #define __strncpy_chk BUILTIN(__strncpy_chk)
475 char *__strncpy_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen);
476 
477 #define strncpy(a,b,n) __strncpy_chk(a,b,n,(size_t)-1)
478 
479 #else /* VARIANT */
480 
481 #define strncpy BUILTIN(strncpy)
482 char *strncpy(char *restrict s1, const char *restrict s2, size_t n);
483 
484 #endif /* VARIANT */
485 
486 
487 void strncpy_null_dst(char *x) {
488   strncpy(NULL, x, 5); // expected-warning{{Null pointer argument in call to string copy function}}
489 }
490 
491 void strncpy_null_src(char *x) {
492   strncpy(x, NULL, 5); // expected-warning{{Null pointer argument in call to string copy function}}
493 }
494 
495 void strncpy_fn(char *x) {
496   strncpy(x, (char*)&strcpy_fn, 5); // expected-warning{{Argument to string copy function is the address of the function 'strcpy_fn', which is not a null-terminated string}}
497 }
498 
499 void strncpy_effects(char *x, char *y) {
500   char a = x[0];
501 
502   clang_analyzer_eval(strncpy(x, y, 5) == x); // expected-warning{{TRUE}}
503   clang_analyzer_eval(strlen(x) == strlen(y)); // expected-warning{{UNKNOWN}}
504   clang_analyzer_eval(a == x[0]); // expected-warning{{UNKNOWN}}
505 }
506 
507 #ifndef SUPPRESS_OUT_OF_BOUND
508 // Enabling the malloc checker enables some of the buffer-checking portions
509 // of the C-string checker.
510 void cstringchecker_bounds_nocrash() {
511   char *p = malloc(2);
512   strncpy(p, "AAA", sizeof("AAA")); // expected-warning {{Size argument is greater than the length of the destination buffer}}
513   free(p);
514 }
515 
516 void strncpy_overflow(char *y) {
517   char x[4];
518   if (strlen(y) == 4)
519     strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}}
520 }
521 
522 void strncpy_no_overflow(char *y) {
523   char x[4];
524   if (strlen(y) == 3)
525     strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}}
526 }
527 
528 void strncpy_no_overflow2(char *y, int n) {
529 	if (n <= 4)
530 		return;
531 
532   char x[4];
533   if (strlen(y) == 3)
534     strncpy(x, y, n); // expected-warning{{Size argument is greater than the length of the destination buffer}}
535 }
536 #endif
537 
538 void strncpy_truncate(char *y) {
539   char x[4];
540   if (strlen(y) == 4)
541     strncpy(x, y, 3); // no-warning
542 }
543 
544 void strncpy_no_truncate(char *y) {
545   char x[4];
546   if (strlen(y) == 3)
547     strncpy(x, y, 3); // no-warning
548 }
549 
550 void strncpy_exactly_matching_buffer(char *y) {
551 	char x[4];
552 	strncpy(x, y, 4); // no-warning
553 
554 	// strncpy does not null-terminate, so we have no idea what the strlen is
555 	// after this.
556   clang_analyzer_eval(strlen(x) > 4); // expected-warning{{UNKNOWN}}
557 }
558 
559 void strncpy_zero(char *src) {
560   char dst[] = "123";
561   strncpy(dst, src, 0); // no-warning
562 }
563 
564 void strncpy_empty() {
565   char dst[] = "123";
566   char src[] = "";
567   strncpy(dst, src, 4); // no-warning
568 }
569 
570 //===----------------------------------------------------------------------===
571 // strncat()
572 //===----------------------------------------------------------------------===
573 
574 #ifdef VARIANT
575 
576 #define __strncat_chk BUILTIN(__strncat_chk)
577 char *__strncat_chk(char *restrict s1, const char *restrict s2, size_t n, size_t destlen);
578 
579 #define strncat(a,b,c) __strncat_chk(a,b,c, (size_t)-1)
580 
581 #else /* VARIANT */
582 
583 #define strncat BUILTIN(strncat)
584 char *strncat(char *restrict s1, const char *restrict s2, size_t n);
585 
586 #endif /* VARIANT */
587 
588 
589 void strncat_null_dst(char *x) {
590   strncat(NULL, x, 4); // expected-warning{{Null pointer argument in call to string copy function}}
591 }
592 
593 void strncat_null_src(char *x) {
594   strncat(x, NULL, 4); // expected-warning{{Null pointer argument in call to string copy function}}
595 }
596 
597 void strncat_fn(char *x) {
598   strncat(x, (char*)&strncat_fn, 4); // expected-warning{{Argument to string copy function is the address of the function 'strncat_fn', which is not a null-terminated string}}
599 }
600 
601 void strncat_effects(char *y) {
602   char x[8] = "123";
603   size_t orig_len = strlen(x);
604   char a = x[0];
605 
606   if (strlen(y) != 4)
607     return;
608 
609   clang_analyzer_eval(strncat(x, y, strlen(y)) == x); // expected-warning{{TRUE}}
610   clang_analyzer_eval(strlen(x) == (orig_len + strlen(y))); // expected-warning{{TRUE}}
611 }
612 
613 #ifndef SUPPRESS_OUT_OF_BOUND
614 void strncat_overflow_0(char *y) {
615   char x[4] = "12";
616   if (strlen(y) == 4)
617     strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}}
618 }
619 
620 void strncat_overflow_1(char *y) {
621   char x[4] = "12";
622   if (strlen(y) == 3)
623     strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}}
624 }
625 
626 void strncat_overflow_2(char *y) {
627   char x[4] = "12";
628   if (strlen(y) == 2)
629     strncat(x, y, strlen(y)); // expected-warning{{Size argument is greater than the free space in the destination buffer}}
630 }
631 
632 void strncat_overflow_3(char *y) {
633   char x[4] = "12";
634   if (strlen(y) == 4)
635     strncat(x, y, 2); // expected-warning{{Size argument is greater than the free space in the destination buffer}}
636 }
637 #endif
638 
639 void strncat_no_overflow_1(char *y) {
640   char x[5] = "12";
641   if (strlen(y) == 2)
642     strncat(x, y, strlen(y)); // no-warning
643 }
644 
645 void strncat_no_overflow_2(char *y) {
646   char x[4] = "12";
647   if (strlen(y) == 4)
648     strncat(x, y, 1); // no-warning
649 }
650 
651 void strncat_symbolic_dst_length(char *dst) {
652   strncat(dst, "1234", 5);
653   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
654 }
655 
656 #ifndef SUPPRESS_OUT_OF_BOUND
657 void strncat_symbolic_src_length(char *src) {
658   char dst[8] = "1234";
659   strncat(dst, src, 3);
660   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
661 
662   char dst2[8] = "1234";
663   strncat(dst2, src, 4); // expected-warning{{Size argument is greater than the free space in the destination buffer}}
664 }
665 
666 void strncat_unknown_src_length(char *src, int offset) {
667   char dst[8] = "1234";
668   strncat(dst, &src[offset], 3);
669   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
670 
671   char dst2[8] = "1234";
672   strncat(dst2, &src[offset], 4); // expected-warning{{Size argument is greater than the free space in the destination buffer}}
673 }
674 #endif
675 
676 // There is no strncat_unknown_dst_length because if we can't get a symbolic
677 // length for the "before" strlen, we won't be able to set one for "after".
678 
679 void strncat_symbolic_limit(unsigned limit) {
680   char dst[6] = "1234";
681   char src[] = "567";
682   strncat(dst, src, limit); // no-warning
683 
684   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
685   clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}}
686 }
687 
688 void strncat_unknown_limit(float limit) {
689   char dst[6] = "1234";
690   char src[] = "567";
691   strncat(dst, src, (size_t)limit); // no-warning
692 
693   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{TRUE}}
694   clang_analyzer_eval(strlen(dst) == 4); // expected-warning{{UNKNOWN}}
695 }
696 
697 void strncat_too_big(char *dst, char *src) {
698   // We assume this will never actually happen, so we don't get a warning.
699   if (strlen(dst) != (((size_t)0) - 2))
700     return;
701   if (strlen(src) != 2)
702     return;
703   strncat(dst, src, 2);
704 }
705 
706 void strncat_zero(char *src) {
707   char dst[] = "123";
708   strncat(dst, src, 0); // no-warning
709 }
710 
711 void strncat_empty() {
712   char dst[8] = "123";
713   char src[] = "";
714   strncat(dst, src, 4); // no-warning
715 }
716 
717 //===----------------------------------------------------------------------===
718 // strcmp()
719 //===----------------------------------------------------------------------===
720 
721 #define strcmp BUILTIN(strcmp)
722 int strcmp(const char * s1, const char * s2);
723 
724 void strcmp_check_modelling() {
725   char *x = "aa";
726   char *y = "a";
727   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
728   clang_analyzer_eval(strcmp(x, y) <= 0); // expected-warning{{FALSE}}
729   clang_analyzer_eval(strcmp(x, y) > 1); // expected-warning{{UNKNOWN}}
730 
731   clang_analyzer_eval(strcmp(y, x) < 0); // expected-warning{{TRUE}}
732   clang_analyzer_eval(strcmp(y, x) >= 0); // expected-warning{{FALSE}}
733   clang_analyzer_eval(strcmp(y, x) < -1); // expected-warning{{UNKNOWN}}
734 }
735 
736 void strcmp_constant0() {
737   clang_analyzer_eval(strcmp("123", "123") == 0); // expected-warning{{TRUE}}
738 }
739 
740 void strcmp_constant_and_var_0() {
741   char *x = "123";
742   clang_analyzer_eval(strcmp(x, "123") == 0); // expected-warning{{TRUE}}
743 }
744 
745 void strcmp_constant_and_var_1() {
746   char *x = "123";
747   clang_analyzer_eval(strcmp("123", x) == 0); // expected-warning{{TRUE}}
748 }
749 
750 void strcmp_0() {
751   char *x = "123";
752   char *y = "123";
753   clang_analyzer_eval(strcmp(x, y) == 0); // expected-warning{{TRUE}}
754 }
755 
756 void strcmp_1() {
757   char *x = "234";
758   char *y = "123";
759   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
760 }
761 
762 void strcmp_2() {
763   char *x = "123";
764   char *y = "234";
765   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
766 }
767 
768 void strcmp_null_0() {
769   char *x = NULL;
770   char *y = "123";
771   strcmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}}
772 }
773 
774 void strcmp_null_1() {
775   char *x = "123";
776   char *y = NULL;
777   strcmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}}
778 }
779 
780 void strcmp_diff_length_0() {
781   char *x = "12345";
782   char *y = "234";
783   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
784 }
785 
786 void strcmp_diff_length_1() {
787   char *x = "123";
788   char *y = "23456";
789   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
790 }
791 
792 void strcmp_diff_length_2() {
793   char *x = "12345";
794   char *y = "123";
795   clang_analyzer_eval(strcmp(x, y) > 0); // expected-warning{{TRUE}}
796 }
797 
798 void strcmp_diff_length_3() {
799   char *x = "123";
800   char *y = "12345";
801   clang_analyzer_eval(strcmp(x, y) < 0); // expected-warning{{TRUE}}
802 }
803 
804 void strcmp_embedded_null () {
805 	clang_analyzer_eval(strcmp("\0z", "\0y") == 0); // expected-warning{{TRUE}}
806 }
807 
808 void strcmp_unknown_arg (char *unknown) {
809 	clang_analyzer_eval(strcmp(unknown, unknown) == 0); // expected-warning{{TRUE}}
810 }
811 
812 union argument {
813    char *f;
814 };
815 
816 void function_pointer_cast_helper(char **a) {
817   strcmp("Hi", *a); // PR24951 crash
818 }
819 
820 void strcmp_union_function_pointer_cast(union argument a) {
821   void (*fPtr)(union argument *) = (void (*)(union argument *))function_pointer_cast_helper;
822 
823   fPtr(&a);
824 }
825 
826 //===----------------------------------------------------------------------===
827 // strncmp()
828 //===----------------------------------------------------------------------===
829 
830 #define strncmp BUILTIN(strncmp)
831 int strncmp(const char *s1, const char *s2, size_t n);
832 
833 void strncmp_check_modelling() {
834   char *x = "aa";
835   char *y = "a";
836   clang_analyzer_eval(strncmp(x, y, 2) > 0); // expected-warning{{TRUE}}
837   clang_analyzer_eval(strncmp(x, y, 2) <= 0); // expected-warning{{FALSE}}
838   clang_analyzer_eval(strncmp(x, y, 2) > 1); // expected-warning{{UNKNOWN}}
839 
840   clang_analyzer_eval(strncmp(y, x, 2) < 0); // expected-warning{{TRUE}}
841   clang_analyzer_eval(strncmp(y, x, 2) >= 0); // expected-warning{{FALSE}}
842   clang_analyzer_eval(strncmp(y, x, 2) < -1); // expected-warning{{UNKNOWN}}
843 }
844 
845 void strncmp_constant0() {
846   clang_analyzer_eval(strncmp("123", "123", 3) == 0); // expected-warning{{TRUE}}
847 }
848 
849 void strncmp_constant_and_var_0() {
850   char *x = "123";
851   clang_analyzer_eval(strncmp(x, "123", 3) == 0); // expected-warning{{TRUE}}
852 }
853 
854 void strncmp_constant_and_var_1() {
855   char *x = "123";
856   clang_analyzer_eval(strncmp("123", x, 3) == 0); // expected-warning{{TRUE}}
857 }
858 
859 void strncmp_0() {
860   char *x = "123";
861   char *y = "123";
862   clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}}
863 }
864 
865 void strncmp_1() {
866   char *x = "234";
867   char *y = "123";
868   clang_analyzer_eval(strncmp(x, y, 3) > 0); // expected-warning{{TRUE}}
869 }
870 
871 void strncmp_2() {
872   char *x = "123";
873   char *y = "234";
874   clang_analyzer_eval(strncmp(x, y, 3) < 0); // expected-warning{{TRUE}}
875 }
876 
877 void strncmp_null_0() {
878   char *x = NULL;
879   char *y = "123";
880   strncmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}}
881 }
882 
883 void strncmp_null_1() {
884   char *x = "123";
885   char *y = NULL;
886   strncmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}}
887 }
888 
889 void strncmp_diff_length_0() {
890   char *x = "12345";
891   char *y = "234";
892   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
893 }
894 
895 void strncmp_diff_length_1() {
896   char *x = "123";
897   char *y = "23456";
898   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
899 }
900 
901 void strncmp_diff_length_2() {
902   char *x = "12345";
903   char *y = "123";
904   clang_analyzer_eval(strncmp(x, y, 5) > 0); // expected-warning{{TRUE}}
905 }
906 
907 void strncmp_diff_length_3() {
908   char *x = "123";
909   char *y = "12345";
910   clang_analyzer_eval(strncmp(x, y, 5) < 0); // expected-warning{{TRUE}}
911 }
912 
913 void strncmp_diff_length_4() {
914   char *x = "123";
915   char *y = "12345";
916   clang_analyzer_eval(strncmp(x, y, 3) == 0); // expected-warning{{TRUE}}
917 }
918 
919 void strncmp_diff_length_5() {
920   char *x = "012";
921   char *y = "12345";
922   clang_analyzer_eval(strncmp(x, y, 3) < 0); // expected-warning{{TRUE}}
923 }
924 
925 void strncmp_diff_length_6() {
926   char *x = "234";
927   char *y = "12345";
928   clang_analyzer_eval(strncmp(x, y, 3) > 0); // expected-warning{{TRUE}}
929 }
930 
931 void strncmp_embedded_null () {
932 	clang_analyzer_eval(strncmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}}
933 }
934 
935 //===----------------------------------------------------------------------===
936 // strcasecmp()
937 //===----------------------------------------------------------------------===
938 
939 #define strcasecmp BUILTIN(strcasecmp)
940 int strcasecmp(const char *s1, const char *s2);
941 
942 void strcasecmp_check_modelling() {
943   char *x = "aa";
944   char *y = "a";
945   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
946   clang_analyzer_eval(strcasecmp(x, y) <= 0); // expected-warning{{FALSE}}
947   clang_analyzer_eval(strcasecmp(x, y) > 1); // expected-warning{{UNKNOWN}}
948 
949   clang_analyzer_eval(strcasecmp(y, x) < 0); // expected-warning{{TRUE}}
950   clang_analyzer_eval(strcasecmp(y, x) >= 0); // expected-warning{{FALSE}}
951   clang_analyzer_eval(strcasecmp(y, x) < -1); // expected-warning{{UNKNOWN}}
952 }
953 
954 void strcasecmp_constant0() {
955   clang_analyzer_eval(strcasecmp("abc", "Abc") == 0); // expected-warning{{TRUE}}
956 }
957 
958 void strcasecmp_constant_and_var_0() {
959   char *x = "abc";
960   clang_analyzer_eval(strcasecmp(x, "Abc") == 0); // expected-warning{{TRUE}}
961 }
962 
963 void strcasecmp_constant_and_var_1() {
964   char *x = "abc";
965   clang_analyzer_eval(strcasecmp("Abc", x) == 0); // expected-warning{{TRUE}}
966 }
967 
968 void strcasecmp_0() {
969   char *x = "abc";
970   char *y = "Abc";
971   clang_analyzer_eval(strcasecmp(x, y) == 0); // expected-warning{{TRUE}}
972 }
973 
974 void strcasecmp_1() {
975   char *x = "Bcd";
976   char *y = "abc";
977   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
978 }
979 
980 void strcasecmp_2() {
981   char *x = "abc";
982   char *y = "Bcd";
983   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
984 }
985 
986 void strcasecmp_null_0() {
987   char *x = NULL;
988   char *y = "123";
989   strcasecmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}}
990 }
991 
992 void strcasecmp_null_1() {
993   char *x = "123";
994   char *y = NULL;
995   strcasecmp(x, y); // expected-warning{{Null pointer argument in call to string comparison function}}
996 }
997 
998 void strcasecmp_diff_length_0() {
999   char *x = "abcde";
1000   char *y = "aBd";
1001   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1002 }
1003 
1004 void strcasecmp_diff_length_1() {
1005   char *x = "abc";
1006   char *y = "aBdef";
1007   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1008 }
1009 
1010 void strcasecmp_diff_length_2() {
1011   char *x = "aBcDe";
1012   char *y = "abc";
1013   clang_analyzer_eval(strcasecmp(x, y) > 0); // expected-warning{{TRUE}}
1014 }
1015 
1016 void strcasecmp_diff_length_3() {
1017   char *x = "aBc";
1018   char *y = "abcde";
1019   clang_analyzer_eval(strcasecmp(x, y) < 0); // expected-warning{{TRUE}}
1020 }
1021 
1022 void strcasecmp_embedded_null () {
1023 	clang_analyzer_eval(strcasecmp("ab\0zz", "ab\0yy") == 0); // expected-warning{{TRUE}}
1024 }
1025 
1026 //===----------------------------------------------------------------------===
1027 // strncasecmp()
1028 //===----------------------------------------------------------------------===
1029 
1030 #define strncasecmp BUILTIN(strncasecmp)
1031 int strncasecmp(const char *s1, const char *s2, size_t n);
1032 
1033 void strncasecmp_check_modelling() {
1034   char *x = "aa";
1035   char *y = "a";
1036   clang_analyzer_eval(strncasecmp(x, y, 2) > 0); // expected-warning{{TRUE}}
1037   clang_analyzer_eval(strncasecmp(x, y, 2) <= 0); // expected-warning{{FALSE}}
1038   clang_analyzer_eval(strncasecmp(x, y, 2) > 1); // expected-warning{{UNKNOWN}}
1039 
1040   clang_analyzer_eval(strncasecmp(y, x, 2) < 0); // expected-warning{{TRUE}}
1041   clang_analyzer_eval(strncasecmp(y, x, 2) >= 0); // expected-warning{{FALSE}}
1042   clang_analyzer_eval(strncasecmp(y, x, 2) < -1); // expected-warning{{UNKNOWN}}
1043 }
1044 
1045 void strncasecmp_constant0() {
1046   clang_analyzer_eval(strncasecmp("abc", "Abc", 3) == 0); // expected-warning{{TRUE}}
1047 }
1048 
1049 void strncasecmp_constant_and_var_0() {
1050   char *x = "abc";
1051   clang_analyzer_eval(strncasecmp(x, "Abc", 3) == 0); // expected-warning{{TRUE}}
1052 }
1053 
1054 void strncasecmp_constant_and_var_1() {
1055   char *x = "abc";
1056   clang_analyzer_eval(strncasecmp("Abc", x, 3) == 0); // expected-warning{{TRUE}}
1057 }
1058 
1059 void strncasecmp_0() {
1060   char *x = "abc";
1061   char *y = "Abc";
1062   clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1063 }
1064 
1065 void strncasecmp_1() {
1066   char *x = "Bcd";
1067   char *y = "abc";
1068   clang_analyzer_eval(strncasecmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1069 }
1070 
1071 void strncasecmp_2() {
1072   char *x = "abc";
1073   char *y = "Bcd";
1074   clang_analyzer_eval(strncasecmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1075 }
1076 
1077 void strncasecmp_null_0() {
1078   char *x = NULL;
1079   char *y = "123";
1080   strncasecmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}}
1081 }
1082 
1083 void strncasecmp_null_1() {
1084   char *x = "123";
1085   char *y = NULL;
1086   strncasecmp(x, y, 3); // expected-warning{{Null pointer argument in call to string comparison function}}
1087 }
1088 
1089 void strncasecmp_diff_length_0() {
1090   char *x = "abcde";
1091   char *y = "aBd";
1092   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1093 }
1094 
1095 void strncasecmp_diff_length_1() {
1096   char *x = "abc";
1097   char *y = "aBdef";
1098   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1099 }
1100 
1101 void strncasecmp_diff_length_2() {
1102   char *x = "aBcDe";
1103   char *y = "abc";
1104   clang_analyzer_eval(strncasecmp(x, y, 5) > 0); // expected-warning{{TRUE}}
1105 }
1106 
1107 void strncasecmp_diff_length_3() {
1108   char *x = "aBc";
1109   char *y = "abcde";
1110   clang_analyzer_eval(strncasecmp(x, y, 5) < 0); // expected-warning{{TRUE}}
1111 }
1112 
1113 void strncasecmp_diff_length_4() {
1114   char *x = "abcde";
1115   char *y = "aBc";
1116   clang_analyzer_eval(strncasecmp(x, y, 3) == 0); // expected-warning{{TRUE}}
1117 }
1118 
1119 void strncasecmp_diff_length_5() {
1120   char *x = "abcde";
1121   char *y = "aBd";
1122   clang_analyzer_eval(strncasecmp(x, y, 3) < 0); // expected-warning{{TRUE}}
1123 }
1124 
1125 void strncasecmp_diff_length_6() {
1126   char *x = "aBDe";
1127   char *y = "abc";
1128   clang_analyzer_eval(strncasecmp(x, y, 3) > 0); // expected-warning{{TRUE}}
1129 }
1130 
1131 void strncasecmp_embedded_null () {
1132 	clang_analyzer_eval(strncasecmp("ab\0zz", "ab\0yy", 4) == 0); // expected-warning{{TRUE}}
1133 }
1134 
1135 //===----------------------------------------------------------------------===
1136 // strsep()
1137 //===----------------------------------------------------------------------===
1138 
1139 char *strsep(char **stringp, const char *delim);
1140 
1141 void strsep_null_delim(char *s) {
1142   strsep(&s, NULL); // expected-warning{{Null pointer argument in call to strsep()}}
1143 }
1144 
1145 void strsep_null_search() {
1146   strsep(NULL, ""); // expected-warning{{Null pointer argument in call to strsep()}}
1147 }
1148 
1149 void strsep_return_original_pointer(char *s) {
1150   char *original = s;
1151   char *result = strsep(&s, ""); // no-warning
1152   clang_analyzer_eval(original == result); // expected-warning{{TRUE}}
1153 }
1154 
1155 void strsep_null_string() {
1156   char *s = NULL;
1157   char *result = strsep(&s, ""); // no-warning
1158   clang_analyzer_eval(result == NULL); // expected-warning{{TRUE}}
1159 }
1160 
1161 void strsep_changes_input_pointer(char *s) {
1162   char *original = s;
1163   strsep(&s, ""); // no-warning
1164   clang_analyzer_eval(s == original); // expected-warning{{UNKNOWN}}
1165   clang_analyzer_eval(s == NULL); // expected-warning{{UNKNOWN}}
1166 
1167   // Check that the value is symbolic.
1168   if (s == NULL) {
1169     clang_analyzer_eval(s == NULL); // expected-warning{{TRUE}}
1170   }
1171 }
1172 
1173 void strsep_changes_input_string() {
1174   char str[] = "abc";
1175 
1176   clang_analyzer_eval(str[1] == 'b'); // expected-warning{{TRUE}}
1177 
1178   char *s = str;
1179   strsep(&s, "b"); // no-warning
1180 
1181   // The real strsep will change the first delimiter it finds into a NUL
1182   // character. For now, we just model the invalidation.
1183   clang_analyzer_eval(str[1] == 'b'); // expected-warning{{UNKNOWN}}
1184 }
1185 
1186 //===----------------------------------------------------------------------===
1187 // memset()
1188 //===----------------------------------------------------------------------===
1189 
1190 void *memset(void *dest, int ch, size_t count);
1191 
1192 void *malloc(size_t size);
1193 void free(void *);
1194 
1195 void memset1_char_array_null() {
1196   char str[] = "abcd";
1197   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1198   memset(str, '\0', 2);
1199   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1200 }
1201 
1202 void memset2_char_array_null() {
1203   char str[] = "abcd";
1204   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1205   memset(str, '\0', strlen(str) + 1);
1206   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1207   clang_analyzer_eval(str[2] == 0);      // expected-warning{{TRUE}}
1208 }
1209 
1210 void memset3_char_malloc_null() {
1211   char *str = (char *)malloc(10 * sizeof(char));
1212   memset(str + 1, '\0', 8);
1213   clang_analyzer_eval(str[1] == 0); // expected-warning{{UNKNOWN}}
1214   free(str);
1215 }
1216 
1217 void memset4_char_malloc_null() {
1218   char *str = (char *)malloc(10 * sizeof(char));
1219   //void *str = malloc(10 * sizeof(char));
1220   memset(str, '\0', 10);
1221   clang_analyzer_eval(str[1] == 0);      // expected-warning{{TRUE}}
1222   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{TRUE}}
1223   free(str);
1224 }
1225 
1226 #ifdef SUPPRESS_OUT_OF_BOUND
1227 void memset5_char_malloc_overflow_null() {
1228   char *str = (char *)malloc(10 * sizeof(char));
1229   memset(str, '\0', 12);
1230   clang_analyzer_eval(str[1] == 0); // expected-warning{{UNKNOWN}}
1231   free(str);
1232 }
1233 #endif
1234 
1235 void memset6_char_array_nonnull() {
1236   char str[] = "abcd";
1237   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1238   memset(str, '0', 2);
1239   clang_analyzer_eval(str[0] == 'a');    // expected-warning{{UNKNOWN}}
1240   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{UNKNOWN}}
1241 }
1242 
1243 #ifdef SUPPRESS_OUT_OF_BOUND
1244 void memset8_char_array_nonnull() {
1245   char str[5] = "abcd";
1246   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1247   memset(str, '0', 10);
1248   clang_analyzer_eval(str[0] != '0');     // expected-warning{{UNKNOWN}}
1249   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1250   clang_analyzer_eval(strlen(str) < 10);  // expected-warning{{FALSE}}
1251 }
1252 #endif
1253 
1254 struct POD_memset {
1255   int num;
1256   char c;
1257 };
1258 
1259 void memset10_struct() {
1260   struct POD_memset pod;
1261   char *str = (char *)&pod;
1262   pod.num = 1;
1263   pod.c = 1;
1264   clang_analyzer_eval(pod.num == 0); // expected-warning{{FALSE}}
1265   memset(str, 0, sizeof(struct POD_memset));
1266   clang_analyzer_eval(pod.num == 0); // expected-warning{{TRUE}}
1267 }
1268 
1269 #ifdef SUPPRESS_OUT_OF_BOUND
1270 void memset11_struct_field() {
1271   struct POD_memset pod;
1272   pod.num = 1;
1273   pod.c = '1';
1274   memset(&pod.num, 0, sizeof(struct POD_memset));
1275 
1276   clang_analyzer_eval(pod.num == 0);  // expected-warning{{TRUE}}
1277   clang_analyzer_eval(pod.c == '\0'); // expected-warning{{TRUE}}
1278 }
1279 
1280 void memset12_struct_field() {
1281   struct POD_memset pod;
1282   pod.num = 1;
1283   pod.c = '1';
1284   memset(&pod.c, 0, sizeof(struct POD_memset));
1285   clang_analyzer_eval(pod.num == 0); // expected-warning{{UNKNOWN}}
1286   clang_analyzer_eval(pod.c == 0);   // expected-warning{{UNKNOWN}}
1287 }
1288 
1289 union U_memset {
1290   int i;
1291   double d;
1292   char c;
1293 };
1294 
1295 void memset13_union_field() {
1296   union U_memset u;
1297   u.i = 5;
1298   memset(&u.i, '\0', sizeof(union U_memset));
1299   // Note: This should be TRUE, analyzer can't handle union perfectly now.
1300   clang_analyzer_eval(u.d == 0); // expected-warning{{UNKNOWN}}
1301 }
1302 #endif
1303 
1304 void memset14_region_cast() {
1305   char *str = (char *)malloc(10 * sizeof(int));
1306   int *array = (int *)str;
1307   memset(array, 0, 10 * sizeof(int));
1308   clang_analyzer_eval(str[10] == '\0');            // expected-warning{{TRUE}}
1309   clang_analyzer_eval(strlen((char *)array) == 0); // expected-warning{{TRUE}}
1310   clang_analyzer_eval(strlen(str) == 0);           // expected-warning{{TRUE}}
1311   free(str);
1312 }
1313 
1314 void memset15_region_cast() {
1315   char *str = (char *)malloc(10 * sizeof(int));
1316   int *array = (int *)str;
1317   memset(array, 0, 5 * sizeof(int));
1318   clang_analyzer_eval(str[10] == '\0');            // expected-warning{{UNKNOWN}}
1319   clang_analyzer_eval(strlen((char *)array) == 0); // expected-warning{{TRUE}}
1320   clang_analyzer_eval(strlen(str) == 0);           // expected-warning{{TRUE}}
1321   free(str);
1322 }
1323 
1324 int memset20_scalar() {
1325   int *x = malloc(sizeof(int));
1326   *x = 10;
1327   memset(x, 0, sizeof(int));
1328   int num = 1 / *x; // expected-warning{{Division by zero}}
1329   free(x);
1330   return num;
1331 }
1332 
1333 int memset21_scalar() {
1334   int *x = malloc(sizeof(int));
1335   memset(x, 0, 1);
1336   int num = 1 / *x;
1337   free(x);
1338   return num;
1339 }
1340 
1341 void memset22_array() {
1342   int array[] = {1, 2, 3, 4, 5, 6, 7, 8, 9};
1343   clang_analyzer_eval(array[1] == 2); // expected-warning{{TRUE}}
1344   memset(array, 0, sizeof(array));
1345   clang_analyzer_eval(array[1] == 0); // expected-warning{{TRUE}}
1346 }
1347 
1348 void memset23_array_pod_object() {
1349   struct POD_memset array[10];
1350   array[1].num = 10;
1351   array[1].c = 'c';
1352   clang_analyzer_eval(array[1].num == 10); // expected-warning{{TRUE}}
1353   memset(&array[1], 0, sizeof(struct POD_memset));
1354   clang_analyzer_eval(array[1].num == 0); // expected-warning{{UNKNOWN}}
1355 }
1356 
1357 void memset24_array_pod_object() {
1358   struct POD_memset array[10];
1359   array[1].num = 10;
1360   array[1].c = 'c';
1361   clang_analyzer_eval(array[1].num == 10); // expected-warning{{TRUE}}
1362   memset(array, 0, sizeof(array));
1363   clang_analyzer_eval(array[1].num == 0); // expected-warning{{TRUE}}
1364 }
1365 
1366 void memset25_symbol(char c) {
1367   char array[10] = {1};
1368   if (c != 0)
1369     return;
1370 
1371   memset(array, c, 10);
1372 
1373   clang_analyzer_eval(strlen(array) == 0); // expected-warning{{TRUE}}
1374   clang_analyzer_eval(array[4] == 0); // expected-warning{{TRUE}}
1375 }
1376 
1377 void memset26_upper_UCHAR_MAX() {
1378   char array[10] = {1};
1379 
1380   memset(array, 1024, 10);
1381 
1382   clang_analyzer_eval(strlen(array) == 0); // expected-warning{{TRUE}}
1383   clang_analyzer_eval(array[4] == 0); // expected-warning{{TRUE}}
1384 }
1385 
1386 //===----------------------------------------------------------------------===
1387 // FIXMEs
1388 //===----------------------------------------------------------------------===
1389 
1390 // The analyzer_eval call below should evaluate to true. We are being too
1391 // aggressive in marking the (length of) src symbol dead. The length of dst
1392 // depends on src. This could be explicitly specified in the checker or the
1393 // logic for handling MetadataSymbol in SymbolManager needs to change.
1394 void strcat_symbolic_src_length(char *src) {
1395 	char dst[8] = "1234";
1396 	strcat(dst, src);
1397   clang_analyzer_eval(strlen(dst) >= 4); // expected-warning{{UNKNOWN}}
1398 }
1399 
1400 
1401 // The analyzer_eval call below should evaluate to true. Most likely the same
1402 // issue as the test above.
1403 void strncpy_exactly_matching_buffer2(char *y) {
1404 	if (strlen(y) >= 4)
1405 		return;
1406 
1407 	char x[4];
1408 	strncpy(x, y, 4); // no-warning
1409 
1410 	// This time, we know that y fits in x anyway.
1411   clang_analyzer_eval(strlen(x) <= 3); // expected-warning{{UNKNOWN}}
1412 }
1413 
1414 void memset7_char_array_nonnull() {
1415   char str[5] = "abcd";
1416   clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}}
1417   memset(str, '0', 5);
1418   // FIXME: This should be TRUE.
1419   clang_analyzer_eval(str[0] == '0');    // expected-warning{{UNKNOWN}}
1420   clang_analyzer_eval(strlen(str) >= 5); // expected-warning{{TRUE}}
1421 }
1422 
1423 void memset16_region_cast() {
1424   char *str = (char *)malloc(10 * sizeof(int));
1425   int *array = (int *)str;
1426   memset(array, '0', 10 * sizeof(int));
1427   // FIXME: This should be TRUE.
1428   clang_analyzer_eval(str[10] == '0');                            // expected-warning{{UNKNOWN}}
1429   clang_analyzer_eval(strlen((char *)array) >= 10 * sizeof(int)); // expected-warning{{TRUE}}
1430   clang_analyzer_eval(strlen(str) >= 10 * sizeof(int));           // expected-warning{{TRUE}}
1431   free(str);
1432 }
1433 
1434 #ifdef SUPPRESS_OUT_OF_BOUND
1435 void memset17_region_cast() {
1436   char *str = (char *)malloc(10 * sizeof(int));
1437   int *array = (int *)str;
1438   memset(array, '0', 12 * sizeof(int));
1439   clang_analyzer_eval(str[10] == '0');                            // expected-warning{{UNKNOWN}}
1440   clang_analyzer_eval(strlen((char *)array) >= 12 * sizeof(int)); // expected-warning{{TRUE}}
1441   clang_analyzer_eval(strlen(str) >= 12 * sizeof(int));           // expected-warning{{TRUE}}
1442   free(str);
1443 }
1444 
1445 void memset18_memset_multiple_times() {
1446   char *str = (char *)malloc(10 * sizeof(char));
1447   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1448 
1449   memset(str + 2, '\0', 10 * sizeof(char));
1450   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1451   clang_analyzer_eval(str[1] == '\0');   // expected-warning{{UNKNOWN}}
1452 
1453   memset(str, '0', 10 * sizeof(char));
1454   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1455   // FIXME: This should be TRUE.
1456   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1457 
1458   free(str);
1459 }
1460 
1461 void memset19_memset_multiple_times() {
1462   char *str = (char *)malloc(10 * sizeof(char));
1463   clang_analyzer_eval(strlen(str) == 0); // expected-warning{{UNKNOWN}}
1464 
1465   memset(str, '0', 10 * sizeof(char));
1466   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}}
1467   // FIXME: This should be TRUE.
1468   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1469 
1470   memset(str + 2, '\0', 10 * sizeof(char));
1471   clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{UNKNOWN}}
1472   clang_analyzer_eval(str[1] == '0');     // expected-warning{{UNKNOWN}}
1473 
1474   free(str);
1475 }
1476 #endif
1477 
1478 // The analyzer does not support binding a symbol with default binding.
1479 void memset27_symbol(char c) {
1480   char array[10] = {0};
1481   if (c < 10)
1482     return;
1483 
1484   memset(array, c, 10);
1485 
1486   clang_analyzer_eval(strlen(array) >= 10); // expected-warning{{TRUE}}
1487   // FIXME: This should be TRUE.
1488   clang_analyzer_eval(array[4] >= 10); // expected-warning{{UNKNOWN}}
1489 }
1490 
1491 void memset28() {
1492   short x;
1493   memset(&x, 1, sizeof(short));
1494   // This should be true.
1495   clang_analyzer_eval(x == 0x101); // expected-warning{{UNKNOWN}}
1496 }
1497