clang/test/SemaCXX/warn-bad-memaccess.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -Wdynamic-class-memaccess -verify %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" int memcmp(void *s1, const void *s2, unsigned n);
   7 extern "C" int bcmp(void *s1, const void *s2, unsigned n);
   8
   9
  10 // Redeclare without the extern "C" to test that we still figure out that this
  11 // is the "real" memset.
  12 void *memset(void *, int, unsigned);
  13
  14 // Several types that should not warn.
  15 struct S1 {} s1;
  16 struct S2 { int x; } s2;
  17 struct S3 { float x, y; S1 s[4]; void (*f)(S1**); } s3;
  18
  19 class C1 {
  20   int x, y, z;
  21 public:
  22   void foo() {}
  23 } c1;
  24
  25 struct X1 { virtual void f(); } x1, x1arr[2];
  26 struct X2 : virtual S1 {} x2;
  27
  28 struct ContainsDynamic { X1 dynamic; } contains_dynamic;
  29 struct DeepContainsDynamic { ContainsDynamic m; } deep_contains_dynamic;
  30 struct ContainsArrayDynamic { X1 dynamic[1]; } contains_array_dynamic;
  31 struct ContainsPointerDynamic { X1 *dynamic; } contains_pointer_dynamic;
  32
  33 void test_warn() {
  34   memset(&x1, 0, sizeof x1); // \
  35       // expected-warning {{destination for this 'memset' call is a pointer to dynamic class}} \
  36       // expected-note {{explicitly cast the pointer to silence this warning}}
  37   memset(x1arr, 0, sizeof x1arr); // \
  38       // expected-warning {{destination for this 'memset' call is a pointer to dynamic class}} \
  39       // expected-note {{explicitly cast the pointer to silence this warning}}
  40   memset((void*)x1arr, 0, sizeof x1arr);
  41   memset(&x2, 0, sizeof x2); // \
  42       // expected-warning {{destination for this 'memset' call is a pointer to dynamic class}} \
  43       // expected-note {{explicitly cast the pointer to silence this warning}}
  44
  45   memmove(&x1, 0, sizeof x1); // \
  46       // expected-warning{{destination for this 'memmove' call is a pointer to dynamic class 'X1'; vtable pointer will be overwritten}} \
  47       // expected-note {{explicitly cast the pointer to silence this warning}}
  48   memmove(0, &x1, sizeof x1); // \
  49       // expected-warning{{source of this 'memmove' call is a pointer to dynamic class 'X1'; vtable pointer will be moved}} \
  50       // expected-note {{explicitly cast the pointer to silence this warning}}
  51   memcpy(&x1, 0, sizeof x1); // \
  52       // expected-warning{{destination for this 'memcpy' call is a pointer to dynamic class 'X1'; vtable pointer will be overwritten}} \
  53       // expected-note {{explicitly cast the pointer to silence this warning}}
  54   memcpy(0, &x1, sizeof x1); // \
  55       // expected-warning{{source of this 'memcpy' call is a pointer to dynamic class 'X1'; vtable pointer will be copied}} \
  56       // expected-note {{explicitly cast the pointer to silence this warning}}
  57   memcmp(&x1, 0, sizeof x1); // \
  58       // expected-warning{{first operand of this 'memcmp' call is a pointer to dynamic class 'X1'; vtable pointer will be compared}} \
  59       // expected-note {{explicitly cast the pointer to silence this warning}}
  60   memcmp(0, &x1, sizeof x1); // \
  61       // expected-warning{{second operand of this 'memcmp' call is a pointer to dynamic class 'X1'; vtable pointer will be compared}} \
  62       // expected-note {{explicitly cast the pointer to silence this warning}}
  63   bcmp(&x1, 0, sizeof x1); // \
  64       // expected-warning{{first operand of this 'bcmp' call is a pointer to dynamic class 'X1'; vtable pointer will be compared}} \
  65       // expected-note {{explicitly cast the pointer to silence this warning}}
  66   bcmp(0, &x1, sizeof x1); // \
  67       // expected-warning{{second operand of this 'bcmp' call is a pointer to dynamic class 'X1'; vtable pointer will be compared}} \
  68       // expected-note {{explicitly cast the pointer to silence this warning}}
  69
  70   __builtin_memset(&x1, 0, sizeof x1); // \
  71       // expected-warning {{destination for this '__builtin_memset' call is a pointer to dynamic class}} \
  72       // expected-note {{explicitly cast the pointer to silence this warning}}
  73   __builtin_memset(&x2, 0, sizeof x2); // \
  74       // expected-warning {{destination for this '__builtin_memset' call is a pointer to dynamic class}} \
  75       // expected-note {{explicitly cast the pointer to silence this warning}}
  76
  77   __builtin_memmove(&x1, 0, sizeof x1); // \
  78       // expected-warning{{destination for this '__builtin_memmove' call is a pointer to dynamic class}} \
  79       // expected-note {{explicitly cast the pointer to silence this warning}}
  80   __builtin_memmove(0, &x1, sizeof x1); // \
  81       // expected-warning{{source of this '__builtin_memmove' call is a pointer to dynamic class}} \
  82       // expected-note {{explicitly cast the pointer to silence this warning}}
  83   __builtin_memcpy(&x1, 0, sizeof x1); // \
  84       // expected-warning{{destination for this '__builtin_memcpy' call is a pointer to dynamic class}} \
  85       // expected-note {{explicitly cast the pointer to silence this warning}}
  86   __builtin_memcpy(0, &x1, sizeof x1); // \
  87       // expected-warning{{source of this '__builtin_memcpy' call is a pointer to dynamic class}} \
  88       // expected-note {{explicitly cast the pointer to silence this warning}}
  89
  90   __builtin___memset_chk(&x1, 0, sizeof x1, sizeof x1); //                    \
  91       // expected-warning {{destination for this '__builtin___memset_chk' call is a pointer to dynamic class}} \
  92       // expected-note {{explicitly cast the pointer to silence this warning}}
  93   __builtin___memset_chk(&x2, 0, sizeof x2, sizeof x2); //                    \
  94       // expected-warning {{destination for this '__builtin___memset_chk' call is a pointer to dynamic class}} \
  95       // expected-note {{explicitly cast the pointer to silence this warning}}
  96
  97   __builtin___memmove_chk(&x1, 0, sizeof x1, sizeof x1); //                   \
  98       // expected-warning{{destination for this '__builtin___memmove_chk' call is a pointer to dynamic class}} \
  99       // expected-note {{explicitly cast the pointer to silence this warning}}
 100   __builtin___memmove_chk(0, &x1, sizeof x1, sizeof x1); //                   \
 101       // expected-warning{{source of this '__builtin___memmove_chk' call is a pointer to dynamic class}} \
 102       // expected-note {{explicitly cast the pointer to silence this warning}}
 103   __builtin___memcpy_chk(&x1, 0, sizeof x1, sizeof x1); //                    \
 104       // expected-warning{{destination for this '__builtin___memcpy_chk' call is a pointer to dynamic class}} \
 105       // expected-note {{explicitly cast the pointer to silence this warning}}
 106   __builtin___memcpy_chk(0, &x1, sizeof x1, sizeof x1); //                    \
 107       // expected-warning{{source of this '__builtin___memcpy_chk' call is a pointer to dynamic class}} \
 108       // expected-note {{explicitly cast the pointer to silence this warning}}
 109
 110   // expected-warning@+2 {{destination for this 'memset' call is a pointer to class containing a dynamic class 'X1'}}
 111   // expected-note@+1 {{explicitly cast the pointer to silence this warning}}
 112   memset(&contains_dynamic, 0, sizeof(contains_dynamic));
 113   // expected-warning@+2 {{destination for this 'memset' call is a pointer to class containing a dynamic class 'X1'}}
 114   // expected-note@+1 {{explicitly cast the pointer to silence this warning}}
 115   memset(&deep_contains_dynamic, 0, sizeof(deep_contains_dynamic));
 116   // expected-warning@+2 {{destination for this 'memset' call is a pointer to class containing a dynamic class 'X1'}}
 117   // expected-note@+1 {{explicitly cast the pointer to silence this warning}}
 118   memset(&contains_array_dynamic, 0, sizeof(contains_array_dynamic));
 119 }
 120
 121 void test_nowarn(void *void_ptr) {
 122   int i, *iptr;
 123   float y;
 124   char c;
 125
 126   memset(&i, 0, sizeof i);
 127   memset(&iptr, 0, sizeof iptr);
 128   memset(&y, 0, sizeof y);
 129   memset(&c, 0, sizeof c);
 130   memset(void_ptr, 0, 42);
 131   memset(&s1, 0, sizeof s1);
 132   memset(&s2, 0, sizeof s2);
 133   memset(&s3, 0, sizeof s3);
 134   memset(&c1, 0, sizeof c1);
 135
 136   memset(&contains_pointer_dynamic, 0, sizeof(contains_pointer_dynamic));
 137
 138   // Unevaluated code shouldn't warn.
 139   (void)sizeof memset(&x1, 0, sizeof x1);
 140
 141   // Dead code shouldn't warn.
 142   if (false) memset(&x1, 0, sizeof x1);
 143 }
 144
 145 namespace N {
 146   void *memset(void *, int, unsigned);
 147   void test_nowarn() {
 148     N::memset(&x1, 0, sizeof x1);
 149   }
 150 }
 151
 152 namespace recursive_class {
 153 struct S {
 154   S v;
 155   // expected-error@-1{{field has incomplete type 'S'}}
 156   // expected-note@-3{{definition of 'recursive_class::S' is not complete until the closing '}'}}
 157 } a;
 158
 159 int main() {
 160   __builtin_memset(&a, 0, sizeof a);
 161   return 0;
 162 }
 163 }