| 1 | // RUN: %clang_analyze_cc1 -x c -analyzer-checker=core -analyzer-output=text -verify %s |
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| 2 | |
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| 3 | #define NULL 0 |
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| 4 | |
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| 5 | int test_noparammacro() { |
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| 6 | int *x = NULL; // expected-note{{'x' initialized to a null pointer value}} |
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| 7 | return *x; // expected-warning{{Dereference of null pointer (loaded from variable 'x')}} |
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| 8 | // expected-note@-1{{Dereference of null pointer (loaded from variable 'x')}} |
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| 9 | } |
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| 10 | |
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| 11 | #define DYN_CAST(X) (X ? (char*)X : 0) |
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| 12 | #define GENERATE_NUMBER(X) (0) |
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| 13 | |
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| 14 | char test_assignment(int *param) { |
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| 15 | char *param2; |
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| 16 | param2 = DYN_CAST(param); |
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| 17 | return *param2; |
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| 18 | } |
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| 19 | |
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| 20 | char test_declaration(int *param) { |
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| 21 | char *param2 = DYN_CAST(param); |
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| 22 | return *param2; |
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| 23 | } |
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| 24 | |
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| 25 | int coin(); |
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| 26 | |
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| 27 | int test_multi_decl(int *paramA, int *paramB) { |
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| 28 | char *param1 = DYN_CAST(paramA), *param2 = DYN_CAST(paramB); |
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| 29 | if (coin()) |
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| 30 | return *param1; |
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| 31 | return *param2; |
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| 32 | } |
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| 33 | |
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| 34 | int testDivision(int a) { |
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| 35 | int divider = GENERATE_NUMBER(2); // expected-note{{'divider' initialized to 0}} |
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| 36 | return 1/divider; // expected-warning{{Division by zero}} |
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| 37 | // expected-note@-1{{Division by zero}} |
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| 38 | } |
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| 39 | |
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| 40 | // Warning should not be suppressed if it happens in the same macro. |
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| 41 | #define DEREF_IN_MACRO(X) int fn() {int *p = 0; return *p; } |
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| 42 | |
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| 43 | DEREF_IN_MACRO(0) // expected-warning{{Dereference of null pointer}} |
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| 44 | // expected-note@-1{{'p' initialized to a null}} |
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| 45 | // expected-note@-2{{Dereference of null pointer}} |
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| 46 | |
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| 47 | // Warning should not be suppressed if the null returned by the macro |
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| 48 | // is not related to the warning. |
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| 49 | #define RETURN_NULL() (0) |
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| 50 | extern int* returnFreshPointer(); |
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| 51 | int noSuppressMacroUnrelated() { |
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| 52 | int *x = RETURN_NULL(); |
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| 53 | x = returnFreshPointer(); // expected-note{{Value assigned to 'x'}} |
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| 54 | if (x) {} // expected-note{{Taking false branch}} |
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| 55 | // expected-note@-1{{Assuming 'x' is null}} |
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| 56 | return *x; // expected-warning{{Dereference of null pointer}} |
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| 57 | // expected-note@-1{{Dereference}} |
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| 58 | } |
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| 59 | |
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| 60 | // Value haven't changed by the assignment, but the null pointer |
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| 61 | // did not come from the macro. |
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| 62 | int noSuppressMacroUnrelatedOtherReason() { |
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| 63 | int *x = RETURN_NULL(); |
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| 64 | x = returnFreshPointer(); |
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| 65 | x = 0; // expected-note{{Null pointer value stored to 'x'}} |
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| 66 | return *x; // expected-warning{{Dereference of null pointer}} |
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| 67 | // expected-note@-1{{Dereference}} |
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| 68 | } |
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| 69 | |
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