326 lines · cpp
1// RUN: %clang_cc1 -verify -std=c++14 %s2 3int foo() {4 int x[2]; // expected-note 4 {{array 'x' declared here}}5 int y[2]; // expected-note 2 {{array 'y' declared here}}6 int z[1]; // expected-note {{array 'z' declared here}}7 int w[1][1]; // expected-note {{array 'w' declared here}}8 int v[1][1][1]; // expected-note {{array 'v' declared here}}9 int *p = &y[2]; // no-warning10 (void) sizeof(x[2]); // no-warning11 y[2] = 2; // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}12 z[1] = 'x'; // expected-warning {{array index 1 is past the end of the array (that has type 'int[1]')}}13 w[0][2] = 0; // expected-warning {{array index 2 is past the end of the array (that has type 'int[1]')}}14 v[0][0][2] = 0; // expected-warning {{array index 2 is past the end of the array (that has type 'int[1]')}}15 return x[2] + // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}16 y[-1] + // expected-warning {{array index -1 is before the beginning of the array}}17 x[sizeof(x)] + // expected-warning {{array index 8 is past the end of the array (that has type 'int[2]')}}18 x[sizeof(x) / sizeof(x[0])] + // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}19 x[sizeof(x) / sizeof(x[0]) - 1] + // no-warning20 x[sizeof(x[2])]; // expected-warning {{array index 4 is past the end of the array (that has type 'int[2]')}}21}22 23// This code example tests that -Warray-bounds works with arrays that24// are template parameters.25template <char *sz> class Qux {26 bool test() { return sz[0] == 'a'; }27};28 29void f1(int a[1]) {30 int val = a[3]; // no warning for function argumnet31}32 33void f2(const int (&a)[2]) { // expected-note {{declared here}}34 int val = a[3]; // expected-warning {{array index 3 is past the end of the array (that has type 'const int[2]')}}35}36 37void test() {38 struct {39 int a[0];40 } s2;41 s2.a[3] = 0; // no warning for 0-sized array42 43 union {44 short a[2]; // expected-note 4 {{declared here}}45 char c[4];46 } u;47 u.a[3] = 1; // expected-warning {{array index 3 is past the end of the array (that has type 'short[2]')}}48 u.c[3] = 1; // no warning49 short *p = &u.a[2]; // no warning50 p = &u.a[3]; // expected-warning {{array index 3 is past the end of the array (that has type 'short[2]')}}51 *(&u.a[2]) = 1; // expected-warning {{array index 2 is past the end of the array (that has type 'short[2]')}}52 *(&u.a[3]) = 1; // expected-warning {{array index 3 is past the end of the array (that has type 'short[2]')}}53 *(&u.c[3]) = 1; // no warning54 55 const int const_subscript = 3;56 int array[2]; // expected-note {{declared here}}57 array[const_subscript] = 0; // expected-warning {{array index 3 is past the end of the array (that has type 'int[2]')}}58 59 int *ptr;60 ptr[3] = 0; // no warning for pointer references61 int array2[] = { 0, 1, 2 }; // expected-note 2 {{declared here}}62 63 array2[3] = 0; // expected-warning {{array index 3 is past the end of the array (that has type 'int[3]')}}64 array2[2+2] = 0; // expected-warning {{array index 4 is past the end of the array (that has type 'int[3]')}}65 66 const char *str1 = "foo";67 char c1 = str1[5]; // no warning for pointers68 69 const char str2[] = "foo"; // expected-note {{declared here}}70 char c2 = str2[5]; // expected-warning {{array index 5 is past the end of the array (that has type 'const char[4]')}}71 72 int (*array_ptr)[2];73 (*array_ptr)[3] = 1; // expected-warning {{array index 3 is past the end of the array (that has type 'int[2]')}}74}75 76template <int I> struct S {77 char arr[I]; // expected-note 3 {{declared here}}78};79template <int I> void f() {80 S<3> s;81 s.arr[4] = 0; // expected-warning 2 {{array index 4 is past the end of the array (that has type 'char[3]')}}82 s.arr[I] = 0; // expected-warning {{array index 5 is past the end of the array (that has type 'char[3]')}}83}84 85void test_templates() {86 f<5>(); // expected-note {{in instantiation}}87}88 89#define SIZE 1090#define ARR_IN_MACRO(flag, arr, idx) flag ? arr[idx] : 191 92int test_no_warn_macro_unreachable() {93 int arr[SIZE]; // expected-note {{array 'arr' declared here}}94 return ARR_IN_MACRO(0, arr, SIZE) + // no-warning95 ARR_IN_MACRO(1, arr, SIZE); // expected-warning{{array index 10 is past the end of the array (that has type 'int[10]')}}96}97 98// This exhibited an assertion failure for a 32-bit build of Clang.99int test_pr9240() {100 short array[100]; // expected-note {{array 'array' declared here}}101 return array[(unsigned long long) 100]; // expected-warning {{array index 100 is past the end of the array (that has type 'short[100]')}}102}103 104// PR 9284 - a template parameter can cause an array bounds access to be105// infeasible.106template <bool extendArray>107void pr9284() {108 int arr[3 + (extendArray ? 1 : 0)];109 110 if (extendArray)111 arr[3] = 42; // no-warning112}113 114template <bool extendArray>115void pr9284b() {116 int arr[3 + (extendArray ? 1 : 0)]; // expected-note {{array 'arr' declared here}}117 118 if (!extendArray)119 arr[3] = 42; // expected-warning{{array index 3 is past the end of the array (that has type 'int[3]')}}120}121 122void test_pr9284() {123 pr9284<true>();124 pr9284<false>();125 pr9284b<true>();126 pr9284b<false>(); // expected-note{{in instantiation of function template specialization 'pr9284b<false>' requested here}}127}128 129int test_pr9296() {130 int array[2];131 return array[true]; // no-warning132}133 134int test_sizeof_as_condition(int flag) {135 int arr[2] = { 0, 0 }; // expected-note {{array 'arr' declared here}}136 if (flag) 137 return sizeof(char) != sizeof(char) ? arr[2] : arr[1];138 return sizeof(char) == sizeof(char) ? arr[2] : arr[1]; // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}139}140 141void test_switch() {142 switch (4) {143 case 1: {144 int arr[2];145 arr[2] = 1; // no-warning146 break;147 }148 case 4: {149 int arr[2]; // expected-note {{array 'arr' declared here}}150 arr[2] = 1; // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}151 break;152 }153 default: {154 int arr[2];155 arr[2] = 1; // no-warning156 break;157 }158 }159}160 161// Test nested switch statements.162enum enumA { enumA_A, enumA_B, enumA_C, enumA_D, enumA_E };163enum enumB { enumB_X, enumB_Y, enumB_Z };164static enum enumB myVal = enumB_X;165void test_nested_switch() {166 switch (enumA_E) { // expected-warning {{no case matching constant}}167 switch (myVal) { // expected-warning {{enumeration values 'enumB_X' and 'enumB_Z' not handled in switch}}168 case enumB_Y: ;169 }170 }171}172 173// Test that if all the values of an enum covered, that the 'default' branch174// is unreachable.175enum Values { A, B, C, D };176void test_all_enums_covered(enum Values v) {177 int x[2];178 switch (v) {179 case A: return;180 case B: return;181 case C: return;182 case D: return;183 }184 x[2] = 0; // no-warning185}186 187namespace tailpad {188 struct foo {189 char c1[1]; // expected-note {{declared here}}190 int x;191 char c2[1];192 };193 194 class baz {195 public:196 char c1[1]; // expected-note {{declared here}}197 int x;198 char c2[1];199 };200 201 char bar(struct foo *F, baz *B) {202 return F->c1[3] + // expected-warning {{array index 3 is past the end of the array (that has type 'char[1]')}}203 F->c2[3] + // no warning, foo could have tail padding allocated.204 B->c1[3] + // expected-warning {{array index 3 is past the end of the array (that has type 'char[1]')}}205 B->c2[3]; // no warning, baz could have tail padding allocated.206 }207}208 209namespace metaprogramming {210#define ONE 1211struct foo {212 char c[ONE]; // expected-note {{array 'c' declared here}}213};214 215 template <int N> struct bar { char c[N]; }; // expected-note {{declared here}}216 217 char test(foo *F, bar<1> *B) {218 return F->c[3] + // expected-warning {{array index 3 is past the end of the array (that has type 'char[1]')}}219 B->c[3]; // expected-warning {{array index 3 is past the end of the array (that has type 'char[1]')}}220 }221}222 223void bar(int x) {}224int test_more() {225 int foo[5]; // expected-note 5 {{array 'foo' declared here}}226 bar(foo[5]); // expected-warning {{array index 5 is past the end of the array (that has type 'int[5]')}}227 ++foo[5]; // expected-warning {{array index 5 is past the end of the array (that has type 'int[5]')}}228 if (foo[6]) // expected-warning {{array index 6 is past the end of the array (that has type 'int[5]')}}229 return --foo[6]; // expected-warning {{array index 6 is past the end of the array (that has type 'int[5]')}}230 else231 return foo[5]; // expected-warning {{array index 5 is past the end of the array (that has type 'int[5]')}}232}233 234void test_pr10771() {235 double foo[4096]; // expected-note {{array 'foo' declared here}}236 237 ((char*)foo)[sizeof(foo) - 1] = '\0'; // no-warning238 *(((char*)foo) + sizeof(foo) - 1) = '\0'; // no-warning239 240 ((char*)foo)[sizeof(foo)] = '\0'; // expected-warning {{array index 32'768 is past the end of the array (that has type 'double[4096]', cast to 'char *')}}241 242 // TODO: This should probably warn, too.243 *(((char*)foo) + sizeof(foo)) = '\0'; // no-warning244}245 246int test_pr11007_aux(const char * restrict, ...);247 248// Test checking with varargs.249void test_pr11007() {250 double a[5]; // expected-note {{array 'a' declared here}}251 test_pr11007_aux("foo", a[1000]); // expected-warning {{array index 1'000 is past the end of the array (that has type 'double[5]')}}252}253 254void test_rdar10916006(void)255{256 int a[128]; // expected-note {{array 'a' declared here}}257 a[(unsigned char)'\xA1'] = 1; // expected-warning {{array index 161 is past the end of the array (that has type 'int[128]')}}258}259 260struct P {261 int a;262 int b;263};264 265void test_struct_array_index() {266 struct P p[10]; // expected-note {{array 'p' declared here}}267 p[11] = {0, 1}; // expected-warning {{array index 11 is past the end of the array (that has type 'struct P[10]')}}268}269 270int operator+(const struct P &s1, const struct P &s2);271int test_operator_overload_struct_array_index() {272 struct P x[10] = {0}; // expected-note {{array 'x' declared here}}273 return x[1] + x[11]; // expected-warning {{array index 11 is past the end of the array (that has type 'struct P[10]')}}274}275 276int multi[2][2][2]; // expected-note 3 {{array 'multi' declared here}}277int test_multiarray() {278 return multi[2][0][0] + // expected-warning {{array index 2 is past the end of the array (that has type 'int[2][2][2]')}}279 multi[0][2][0] + // expected-warning {{array index 2 is past the end of the array (that has type 'int[2][2]')}}280 multi[0][0][2]; // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}281}282 283struct multi_s {284 int arr[4];285};286struct multi_s multi2[4]; // expected-note {{array 'multi2' declared here}}287int test_struct_multiarray() {288 return multi2[4].arr[0]; // expected-warning {{array index 4 is past the end of the array (that has type 'struct multi_s[4]')}}289}290 291namespace PR39746 {292 struct S;293 extern S xxx[2]; // expected-note {{array 'xxx' declared here}}294 class C {};295 296 C &f() { return reinterpret_cast<C *>(xxx)[1]; } // no-warning297 // We have no info on whether this is out-of-bounds.298 C &g() { return reinterpret_cast<C *>(xxx)[2]; } // no-warning299 // We can still diagnose this.300 C &h() { return reinterpret_cast<C *>(xxx)[-1]; } // expected-warning {{array index -1 is before the beginning of the array}}301}302 303namespace PR41087 {304 template <typename Ty> void foo() {305 Ty buffer[2]; // expected-note 3{{array 'buffer' declared here}}306 ((char *)buffer)[2] = 'A'; // expected-warning 1{{array index 2 is past the end of the array (that has type 'char[2]', cast to 'char *')}}307 ((char *)buffer)[-1] = 'A'; // expected-warning 2{{array index -1 is before the beginning of the array}}308 }309 310 void f() {311 foo<char>(); // expected-note 1{{in instantiation of function template specialization}}312 foo<int>(); // expected-note 1{{in instantiation of function template specialization}}313 };314}315 316namespace var_template_array {317template <typename T> int arr[2]; // expected-note {{array 'arr<int>' declared here}}318template <> int arr<float>[1]; // expected-note {{array 'arr<float>' declared here}}319 320void test() {321 arr<int>[1] = 0; // ok322 arr<int>[2] = 0; // expected-warning {{array index 2 is past the end of the array (that has type 'int[2]')}}323 arr<float>[1] = 0; // expected-warning {{array index 1 is past the end of the array (that has type 'int[1]')}}324}325} // namespace var_template_array326