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Diffstat (limited to 'clang/test/Analysis/string-fail.c')
-rw-r--r-- | clang/test/Analysis/string-fail.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/clang/test/Analysis/string-fail.c b/clang/test/Analysis/string-fail.c new file mode 100644 index 0000000..3bff6d4 --- /dev/null +++ b/clang/test/Analysis/string-fail.c @@ -0,0 +1,113 @@ +// RUN: %clang_cc1 -analyze -analyzer-checker=core,experimental.unix.CString,experimental.deadcode.UnreachableCode -analyzer-store=region -Wno-null-dereference -verify %s +// RUN: %clang_cc1 -analyze -DUSE_BUILTINS -analyzer-checker=core,experimental.unix.CString,experimental.deadcode.UnreachableCode -analyzer-store=region -Wno-null-dereference -verify %s +// XFAIL: * + +// This file is for tests that may eventually go into string.c, or may be +// deleted outright. At one point these tests passed, but only because we +// weren't correctly modelling the behavior of the relevant string functions. +// The tests aren't incorrect, but require the analyzer to be smarter about +// conjured values than it currently is. + +//===----------------------------------------------------------------------=== +// Declarations +//===----------------------------------------------------------------------=== + +// Some functions are so similar to each other that they follow the same code +// path, such as memcpy and __memcpy_chk, or memcmp and bcmp. If VARIANT is +// defined, make sure to use the variants instead to make sure they are still +// checked by the analyzer. + +// Some functions are implemented as builtins. These should be #defined as +// BUILTIN(f), which will prepend "__builtin_" if USE_BUILTINS is defined. + +// Functions that have variants and are also available as builtins should be +// declared carefully! See memcpy() for an example. + +#ifdef USE_BUILTINS +# define BUILTIN(f) __builtin_ ## f +#else /* USE_BUILTINS */ +# define BUILTIN(f) f +#endif /* USE_BUILTINS */ + +#define NULL 0 +typedef typeof(sizeof(int)) size_t; + + +//===----------------------------------------------------------------------=== +// strnlen() +//===----------------------------------------------------------------------=== + +#define strnlen BUILTIN(strnlen) +size_t strnlen(const char *s, size_t maxlen); + +void strnlen_liveness(const char *x) { + if (strnlen(x, 10) < 5) + return; + if (strnlen(x, 10) < 5) + (void)*(char*)0; // no-warning +} + +void strnlen_subregion() { + struct two_stringsn { char a[2], b[2]; }; + extern void use_two_stringsn(struct two_stringsn *); + + struct two_stringsn z; + use_two_stringsn(&z); + + size_t a = strnlen(z.a, 10); + z.b[0] = 5; + size_t b = strnlen(z.a, 10); + if (a == 0 && b != 0) + (void)*(char*)0; // expected-warning{{never executed}} + + use_two_stringsn(&z); + + size_t c = strnlen(z.a, 10); + if (a == 0 && c != 0) + (void)*(char*)0; // expected-warning{{null}} +} + +extern void use_stringn(char *); +void strnlen_argument(char *x) { + size_t a = strnlen(x, 10); + size_t b = strnlen(x, 10); + if (a == 0 && b != 0) + (void)*(char*)0; // expected-warning{{never executed}} + + use_stringn(x); + + size_t c = strnlen(x, 10); + if (a == 0 && c != 0) + (void)*(char*)0; // expected-warning{{null}} +} + +extern char global_strn[]; +void strnlen_global() { + size_t a = strnlen(global_strn, 10); + size_t b = strnlen(global_strn, 10); + if (a == 0 && b != 0) + (void)*(char*)0; // expected-warning{{never executed}} + + // Call a function with unknown effects, which should invalidate globals. + use_stringn(0); + + size_t c = strnlen(global_strn, 10); + if (a == 0 && c != 0) + (void)*(char*)0; // expected-warning{{null}} +} + +void strnlen_indirect(char *x) { + size_t a = strnlen(x, 10); + char *p = x; + char **p2 = &p; + size_t b = strnlen(x, 10); + if (a == 0 && b != 0) + (void)*(char*)0; // expected-warning{{never executed}} + + extern void use_stringn_ptr(char*const*); + use_stringn_ptr(p2); + + size_t c = strnlen(x, 10); + if (a == 0 && c != 0) + (void)*(char*)0; // expected-warning{{null}} +} |