Tom Care | 4895b9c | 2010-10-06 23:02:25 +0000 | [diff] [blame] | 1 | // RUN: %clang_cc1 -analyze -analyzer-experimental-checks -analyzer-check-objc-mem -analyzer-check-dead-stores -verify -analyzer-opt-analyze-nested-blocks -Wno-unused-value %s |
Tom Care | c4b5bd8 | 2010-07-23 23:04:53 +0000 | [diff] [blame] | 2 | |
| 3 | extern void foo(int a); |
| 4 | |
Tom Care | 7bce3a1 | 2010-07-27 23:30:21 +0000 | [diff] [blame] | 5 | // The first few tests are non-path specific - we should be able to find them |
| 6 | |
Tom Care | c4b5bd8 | 2010-07-23 23:04:53 +0000 | [diff] [blame] | 7 | void test(unsigned a) { |
| 8 | switch (a) { |
| 9 | a += 5; // expected-warning{{never executed}} |
| 10 | case 2: |
| 11 | a *= 10; |
| 12 | case 3: |
| 13 | a %= 2; |
| 14 | } |
| 15 | foo(a); |
| 16 | } |
| 17 | |
| 18 | void test2(unsigned a) { |
| 19 | help: |
| 20 | if (a > 0) |
| 21 | return; |
| 22 | if (a == 0) |
| 23 | return; |
| 24 | foo(a); // expected-warning{{never executed}} |
| 25 | goto help; |
| 26 | } |
| 27 | |
Tom Care | 7bce3a1 | 2010-07-27 23:30:21 +0000 | [diff] [blame] | 28 | void test3(unsigned a) { |
| 29 | while(1); |
| 30 | if (a > 5) { // expected-warning{{never executed}} |
| 31 | return; |
| 32 | } |
| 33 | } |
| 34 | |
| 35 | // These next tests are path-sensitive |
| 36 | |
| 37 | void test4() { |
Tom Care | c4b5bd8 | 2010-07-23 23:04:53 +0000 | [diff] [blame] | 38 | int a = 5; |
| 39 | |
| 40 | while (a > 1) |
| 41 | a -= 2; |
| 42 | |
| 43 | if (a > 1) { |
| 44 | a = a + 56; // expected-warning{{never executed}} |
| 45 | } |
| 46 | |
| 47 | foo(a); |
| 48 | } |
| 49 | |
Tom Care | c4b5bd8 | 2010-07-23 23:04:53 +0000 | [diff] [blame] | 50 | extern void bar(char c); |
| 51 | |
| 52 | void test5(const char *c) { |
| 53 | foo(c[0]); |
| 54 | |
| 55 | if (!c) { |
| 56 | bar(1); // expected-warning{{never executed}} |
| 57 | } |
| 58 | } |
| 59 | |
Tom Care | 7bce3a1 | 2010-07-27 23:30:21 +0000 | [diff] [blame] | 60 | // These next tests are false positives and should not generate warnings |
| 61 | |
Jordy Rose | 5e04bdd | 2010-07-27 03:39:53 +0000 | [diff] [blame] | 62 | void test6(const char *c) { |
| 63 | if (c) return; |
| 64 | if (!c) return; |
| 65 | __builtin_unreachable(); // no-warning |
| 66 | } |
| 67 | |
Tom Care | 7bce3a1 | 2010-07-27 23:30:21 +0000 | [diff] [blame] | 68 | // Compile-time constant false positives |
| 69 | #define CONSTANT 0 |
| 70 | enum test_enum { Off, On }; |
| 71 | void test7() { |
| 72 | if (CONSTANT) |
| 73 | return; // no-warning |
| 74 | |
| 75 | if (sizeof(int)) |
| 76 | return; // no-warning |
| 77 | |
| 78 | if (Off) |
| 79 | return; // no-warning |
| 80 | } |
| 81 | |
| 82 | void test8() { |
| 83 | static unsigned a = 0; |
| 84 | |
| 85 | if (a) |
| 86 | a = 123; // no-warning |
| 87 | |
| 88 | a = 5; |
| 89 | } |
| 90 | |
Tom Care | 0600918 | 2010-08-05 17:53:44 +0000 | [diff] [blame] | 91 | // Check for bugs where multiple statements are reported |
| 92 | void test9(unsigned a) { |
| 93 | switch (a) { |
| 94 | if (a) // expected-warning{{never executed}} |
| 95 | foo(a + 5); // no-warning |
Tom Care | 4895b9c | 2010-10-06 23:02:25 +0000 | [diff] [blame] | 96 | else // no-warning |
| 97 | foo(a); // no-warning |
Tom Care | 0600918 | 2010-08-05 17:53:44 +0000 | [diff] [blame] | 98 | case 1: |
| 99 | case 2: |
| 100 | break; |
| 101 | default: |
| 102 | break; |
| 103 | } |
| 104 | } |
Tom Care | 4895b9c | 2010-10-06 23:02:25 +0000 | [diff] [blame] | 105 | |
| 106 | // Tests from flow-sensitive version |
| 107 | void test10() { |
| 108 | goto c; |
| 109 | d: |
| 110 | goto e; // expected-warning {{never executed}} |
| 111 | c: ; |
| 112 | int i; |
| 113 | return; |
| 114 | goto b; // expected-warning {{never executed}} |
| 115 | goto a; // expected-warning {{never executed}} |
| 116 | b: |
| 117 | i = 1; // expected-warning {{Value stored to 'i' is never read}} |
| 118 | a: |
| 119 | i = 2; // expected-warning {{Value stored to 'i' is never read}} |
| 120 | goto f; |
| 121 | e: |
| 122 | goto d; |
| 123 | f: ; |
| 124 | } |