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Diffstat (limited to 'clang/test/Analysis/null-deref-ps.c')
-rw-r--r-- | clang/test/Analysis/null-deref-ps.c | 313 |
1 files changed, 313 insertions, 0 deletions
diff --git a/clang/test/Analysis/null-deref-ps.c b/clang/test/Analysis/null-deref-ps.c new file mode 100644 index 0000000..a707970 --- /dev/null +++ b/clang/test/Analysis/null-deref-ps.c @@ -0,0 +1,313 @@ +// RUN: %clang_cc1 -triple i386-apple-darwin10 -analyze -analyzer-checker=core,deadcode,experimental.deadcode.IdempotentOperations,experimental.core -std=gnu99 -analyzer-store=region -analyzer-constraints=range -analyzer-purge=none -verify %s -Wno-error=return-type +// RUN: %clang_cc1 -triple i386-apple-darwin10 -analyze -analyzer-checker=core,deadcode,experimental.deadcode.IdempotentOperations,experimental.core -std=gnu99 -analyzer-store=region -analyzer-constraints=range -verify %s -Wno-error=return-type + +typedef unsigned uintptr_t; + +extern void __assert_fail (__const char *__assertion, __const char *__file, + unsigned int __line, __const char *__function) + __attribute__ ((__noreturn__)); + +#define assert(expr) \ + ((expr) ? (void)(0) : __assert_fail (#expr, __FILE__, __LINE__, __func__)) + +void f1(int *p) { + if (p) *p = 1; + else *p = 0; // expected-warning{{ereference}} +} + +struct foo_struct { + int x; +}; + +int f2(struct foo_struct* p) { + + if (p) + p->x = 1; + + return p->x++; // expected-warning{{Access to field 'x' results in a dereference of a null pointer (loaded from variable 'p')}} +} + +int f3(char* x) { + + int i = 2; + + if (x) + return x[i - 1]; + + return x[i+1]; // expected-warning{{Array access (from variable 'x') results in a null pointer dereference}} +} + +int f3_b(char* x) { + + int i = 2; + + if (x) + return x[i - 1]; + + return x[i+1]++; // expected-warning{{Array access (from variable 'x') results in a null pointer dereference}} +} + +int f4(int *p) { + + uintptr_t x = (uintptr_t) p; + + if (x) + return 1; + + int *q = (int*) x; + return *q; // expected-warning{{Dereference of null pointer (loaded from variable 'q')}} +} + +int f4_b() { + short array[2]; + uintptr_t x = array; // expected-warning{{incompatible pointer to integer conversion}} + short *p = x; // expected-warning{{incompatible integer to pointer conversion}} + + // The following branch should be infeasible. + if (!(p == &array[0])) { // expected-warning{{Both operands to '==' always have the same value}} + p = 0; + *p = 1; // no-warning + } + + if (p) { + *p = 5; // no-warning + p = 0; + } + else return; // expected-warning {{non-void function 'f4_b' should return a value}} + + *p += 10; // expected-warning{{Dereference of null pointer}} + return 0; +} + +int f5() { + + char *s = "hello world"; + return s[0]; // no-warning +} + +int bar(int* p, int q) __attribute__((nonnull)); + +int f6(int *p) { + return !p ? bar(p, 1) // expected-warning {{Null pointer passed as an argument to a 'nonnull' parameter}} + : bar(p, 0); // no-warning +} + +int bar2(int* p, int q) __attribute__((nonnull(1))); + +int f6b(int *p) { + return !p ? bar2(p, 1) // expected-warning {{Null pointer passed as an argument to a 'nonnull' parameter}} + : bar2(p, 0); // no-warning +} + +int bar3(int*p, int q, int *r) __attribute__((nonnull(1,3))); + +int f6c(int *p, int *q) { + return !p ? bar3(q, 2, p) // expected-warning {{Null pointer passed as an argument to a 'nonnull' parameter}} + : bar3(p, 2, q); // no-warning +} + +void f6d(int *p) { + bar(p, 0); + // At this point, 'p' cannot be null. + if (!p) { + int *q = 0; + *q = 0xDEADBEEF; // no-warning + } +} + +void f6e(int *p, int offset) { + // PR7406 - crash from treating an UnknownVal as defined, to see if it's 0. + bar((p+offset)+1, 0); // not crash +} + +int* qux(); + +int f7(int x) { + + int* p = 0; + + if (0 == x) + p = qux(); + + if (0 == x) + *p = 1; // no-warning + + return x; +} + +int* f7b(int *x) { + + int* p = 0; + + if (((void*)0) == x) + p = qux(); + + if (((void*)0) == x) + *p = 1; // no-warning + + return x; +} + +int* f7c(int *x) { + + int* p = 0; + + if (((void*)0) == x) + p = qux(); + + if (((void*)0) != x) + return x; + + // If we reach here then 'p' is not null. + *p = 1; // no-warning + return x; +} + +int* f7c2(int *x) { + + int* p = 0; + + if (((void*)0) == x) + p = qux(); + + if (((void*)0) == x) + return x; + + *p = 1; // expected-warning{{null}} + return x; +} + + +void f8(int *p, int *q) { + if (!p) + if (p) + *p = 1; // no-warning + + if (q) + if (!q) + *q = 1; // no-warning +} + +int* qux(); + +int f9(unsigned len) { + assert (len != 0); + int *p = 0; + unsigned i; + + for (i = 0; i < len; ++i) + p = qux(i); + + return *p++; // no-warning +} + +int f9b(unsigned len) { + assert (len > 0); // note use of '>' + int *p = 0; + unsigned i; + + for (i = 0; i < len; ++i) + p = qux(i); + + return *p++; // no-warning +} + +int* f10(int* p, signed char x, int y) { + // This line tests symbolication with compound assignments where the + // LHS and RHS have different bitwidths. The new symbolic value + // for 'x' should have a bitwidth of 8. + x &= y; + + // This tests that our symbolication worked, and that we correctly test + // x against 0 (with the same bitwidth). + if (!x) { + if (!p) return 0; + *p = 10; + } + else p = 0; + + if (!x) + *p = 5; // no-warning + + return p; +} + +// Test case from <rdar://problem/6407949> +void f11(unsigned i) { + int *x = 0; + if (i >= 0) { // expected-warning{{always true}} + // always true + } else { + *x = 42; // no-warning + } +} + +void f11b(unsigned i) { + int *x = 0; + if (i <= ~(unsigned)0) { + // always true + } else { + *x = 42; // no-warning + } +} + +// Test case for switch statements with weird case arms. +typedef int BOOL, *PBOOL, *LPBOOL; +typedef long LONG_PTR, *PLONG_PTR; +typedef unsigned long ULONG_PTR, *PULONG_PTR; +typedef ULONG_PTR DWORD_PTR, *PDWORD_PTR; +typedef LONG_PTR LRESULT; +typedef struct _F12ITEM *HF12ITEM; + +void f12(HF12ITEM i, char *q) { + char *p = 0; + switch ((DWORD_PTR) i) { + case 0 ... 10: + p = q; + break; + case (DWORD_PTR) ((HF12ITEM) - 65535): + return; + default: + return; + } + + *p = 1; // no-warning +} + +// Test handling of translating between integer "pointers" and back. +void f13() { + int *x = 0; + if (((((int) x) << 2) + 1) >> 1) *x = 1; +} + +// PR 4759 - Attribute non-null checking by the analyzer was not correctly +// handling pointer values that were undefined. +void pr4759_aux(int *p) __attribute__((nonnull)); + +void pr4759() { + int *p; + pr4759_aux(p); // expected-warning{{Function call argument is an uninitialized value}} +} + +// Relax function call arguments invalidation to be aware of const +// arguments. Test with function pointers. radar://10595327 +void ttt(const int *nptr); +void ttt2(const int *nptr); +typedef void (*NoConstType)(int*); +int foo10595327(int b) { + void (*fp)(int *); + // We use path sensitivity to get the function declaration. Even when the + // function pointer is cast to non pointer-to-const parameter type, we can + // find the right function declaration. + if (b > 5) + fp = (NoConstType)ttt2; + else + fp = (NoConstType)ttt; + int x = 3; + int y = x + 1; + int *p = 0; + fp(&y); + if (x == y) + return *p; // no-warning + return 0; +} |