1 // RUN: %clang_cc1 -fsyntax-only -verify -Wno-sizeof-array-argument %s 2 // 3 extern "C" void *memset(void *, int, unsigned); 4 extern "C" void *memmove(void *s1, const void *s2, unsigned n); 5 extern "C" void *memcpy(void *s1, const void *s2, unsigned n); 6 extern "C" void *memcmp(void *s1, const void *s2, unsigned n); 7 8 struct S {int a, b, c, d;}; 9 typedef S* PS; 10 11 struct Foo {}; 12 typedef const Foo& CFooRef; 13 typedef const Foo CFoo; 14 typedef volatile Foo VFoo; 15 typedef const volatile Foo CVFoo; 16 17 typedef double Mat[4][4]; 18 19 template <class Dest, class Source> 20 inline Dest bit_cast(const Source& source) { 21 Dest dest; 22 memcpy(&dest, &source, sizeof(dest)); 23 return dest; 24 } 25 26 // http://www.lysator.liu.se/c/c-faq/c-2.html#2-6 27 void f(Mat m, const Foo& const_foo, char *buffer) { 28 S s; 29 S* ps = &s; 30 PS ps2 = &s; 31 char arr[5]; 32 char* parr[5]; 33 Foo foo; 34 char* heap_buffer = new char[42]; 35 36 /* Should warn */ 37 memset(&s, 0, sizeof(&s)); // \ 38 // expected-warning {{argument to 'sizeof' in 'memset' call is the same expression as the destination}} 39 memset(ps, 0, sizeof(ps)); // \ 40 // expected-warning {{argument to 'sizeof' in 'memset' call is the same expression as the destination}} 41 memset(ps2, 0, sizeof(ps2)); // \ 42 // expected-warning {{argument to 'sizeof' in 'memset' call is the same expression as the destination}} 43 memset(ps2, 0, sizeof(typeof(ps2))); // \ 44 // expected-warning {{argument to 'sizeof' in 'memset' call is the same pointer type}} 45 memset(ps2, 0, sizeof(PS)); // \ 46 // expected-warning {{argument to 'sizeof' in 'memset' call is the same pointer type}} 47 memset(heap_buffer, 0, sizeof(heap_buffer)); // \ 48 // expected-warning {{argument to 'sizeof' in 'memset' call is the same expression as the destination}} 49 50 memcpy(&s, 0, sizeof(&s)); // \ 51 // expected-warning {{argument to 'sizeof' in 'memcpy' call is the same expression as the destination}} 52 memcpy(0, &s, sizeof(&s)); // \ 53 // expected-warning {{argument to 'sizeof' in 'memcpy' call is the same expression as the source}} 54 55 memmove(ps, 0, sizeof(ps)); // \ 56 // expected-warning {{argument to 'sizeof' in 'memmove' call is the same expression as the destination}} 57 memcmp(ps, 0, sizeof(ps)); // \ 58 // expected-warning {{argument to 'sizeof' in 'memcmp' call is the same expression as the destination}} 59 60 /* Shouldn't warn */ 61 memset((void*)&s, 0, sizeof(&s)); 62 memset(&s, 0, sizeof(s)); 63 memset(&s, 0, sizeof(S)); 64 memset(&s, 0, sizeof(const S)); 65 memset(&s, 0, sizeof(volatile S)); 66 memset(&s, 0, sizeof(volatile const S)); 67 memset(&foo, 0, sizeof(CFoo)); 68 memset(&foo, 0, sizeof(VFoo)); 69 memset(&foo, 0, sizeof(CVFoo)); 70 memset(ps, 0, sizeof(*ps)); 71 memset(ps2, 0, sizeof(*ps2)); 72 memset(ps2, 0, sizeof(typeof(*ps2))); 73 memset(arr, 0, sizeof(arr)); 74 memset(parr, 0, sizeof(parr)); 75 76 memcpy(&foo, &const_foo, sizeof(Foo)); 77 memcpy((void*)&s, 0, sizeof(&s)); 78 memcpy(0, (void*)&s, sizeof(&s)); 79 char *cptr; 80 memcpy(&cptr, buffer, sizeof(cptr)); 81 memcpy((char*)&cptr, buffer, sizeof(cptr)); 82 83 CFooRef cfoo = foo; 84 memcpy(&foo, &cfoo, sizeof(Foo)); 85 86 memcpy(0, &arr, sizeof(arr)); 87 typedef char Buff[8]; 88 memcpy(0, &arr, sizeof(Buff)); 89 90 unsigned char* puc; 91 bit_cast<char*>(puc); 92 93 float* pf; 94 bit_cast<int*>(pf); 95 96 int iarr[14]; 97 memset(&iarr[0], 0, sizeof iarr); 98 99 int* iparr[14]; 100 memset(&iparr[0], 0, sizeof iparr); 101 102 memset(m, 0, sizeof(Mat)); 103 104 // Copy to raw buffer shouldn't warn either 105 memcpy(&foo, &arr, sizeof(Foo)); 106 memcpy(&arr, &foo, sizeof(Foo)); 107 } 108 109 namespace ns { 110 void memset(void* s, char c, int n); 111 void f(int* i) { 112 memset(i, 0, sizeof(i)); 113 } 114 } 115 116 extern "C" int strncmp(const char *s1, const char *s2, unsigned n); 117 extern "C" int strncasecmp(const char *s1, const char *s2, unsigned n); 118 extern "C" char *strncpy(char *det, const char *src, unsigned n); 119 extern "C" char *strncat(char *dst, const char *src, unsigned n); 120 extern "C" char *strndup(const char *src, unsigned n); 121 122 void strcpy_and_friends() { 123 const char* FOO = "<- should be an array instead"; 124 const char* BAR = "<- this, too"; 125 126 strncmp(FOO, BAR, sizeof(FOO)); // \ 127 // expected-warning {{argument to 'sizeof' in 'strncmp' call is the same expression as the destination}} 128 strncasecmp(FOO, BAR, sizeof(FOO)); // \ 129 // expected-warning {{argument to 'sizeof' in 'strncasecmp' call is the same expression as the destination}} 130 131 char buff[80]; 132 133 strncpy(buff, BAR, sizeof(BAR)); // \ 134 // expected-warning {{argument to 'sizeof' in 'strncpy' call is the same expression as the source}} 135 strndup(FOO, sizeof(FOO)); // \ 136 // expected-warning {{argument to 'sizeof' in 'strndup' call is the same expression as the source}} 137 } 138