1 // RUN: %clang_cc1 -fsyntax-only -verify -Wvla-extension %s 2 struct NonPOD { 3 NonPOD(); 4 }; 5 6 struct NonPOD2 { 7 NonPOD np; 8 }; 9 10 struct POD { 11 int x; 12 int y; 13 }; 14 15 // We allow VLAs of POD types, only. 16 void vla(int N) { 17 int array1[N]; // expected-warning{{variable length arrays are a C99 feature}} 18 POD array2[N]; // expected-warning{{variable length arrays are a C99 feature}} 19 NonPOD array3[N]; // expected-error{{variable length array of non-POD element type 'NonPOD'}} 20 NonPOD2 array4[N][3]; // expected-error{{variable length array of non-POD element type 'NonPOD2'}} 21 } 22 23 /// Warn about VLAs in templates. 24 template<typename T> 25 void vla_in_template(int N, T t) { 26 int array1[N]; // expected-warning{{variable length arrays are a C99 feature}} 27 } 28 29 struct HasConstantValue { 30 static const unsigned int value = 2; 31 }; 32 33 struct HasNonConstantValue { 34 static unsigned int value; 35 }; 36 37 template<typename T> 38 void vla_in_template(T t) { 39 int array2[T::value]; // expected-warning{{variable length arrays are a C99 feature}} 40 } 41 42 template void vla_in_template<HasConstantValue>(HasConstantValue); 43 template void vla_in_template<HasNonConstantValue>(HasNonConstantValue); // expected-note{{instantiation of}} 44 45 template<typename T> struct X0 { }; 46 47 // Cannot use any variably-modified type with a template parameter or 48 // argument. 49 void inst_with_vla(int N) { 50 int array[N]; // expected-warning{{variable length arrays are a C99 feature}} 51 X0<__typeof__(array)> x0a; // expected-error{{variably modified type 'typeof (array)' (aka 'int [N]') cannot be used as a template argument}} 52 } 53 54 template<typename T> 55 struct X1 { 56 template<int (&Array)[T::value]> // expected-error{{non-type template parameter of variably modified type 'int (&)[HasNonConstantValue::value]'}} \ 57 // expected-warning{{variable length arrays are a C99 feature}} 58 struct Inner { 59 60 }; 61 }; 62 63 X1<HasConstantValue> x1a; 64 X1<HasNonConstantValue> x1b; // expected-note{{in instantiation of}} 65 66 // Template argument deduction does not allow deducing a size from a VLA. 67 // FIXME: This diagnostic should make it clear that the two 'N's are different entities! 68 template<typename T, unsigned N> 69 void accept_array(T (&array)[N]); // expected-note{{candidate template ignored: could not match 'T [N]' against 'int [N]'}} 70 71 void test_accept_array(int N) { 72 int array[N]; // expected-warning{{variable length arrays are a C99 feature}} 73 accept_array(array); // expected-error{{no matching function for call to 'accept_array'}} 74 } 75 76 // Variably-modified types cannot be used in local classes. 77 void local_classes(int N) { // expected-note {{declared here}} 78 struct X { 79 int size; 80 int array[N]; // expected-error{{fields must have a constant size: 'variable length array in structure' extension will never be supported}} \ 81 // expected-error{{reference to local variable 'N' declared in enclosing function 'local_classes'}} \ 82 // expected-warning{{variable length arrays are a C99 feature}} 83 }; 84 } 85 86 namespace PR7206 { 87 void f(int x) { 88 struct edge_info { 89 float left; 90 float right; 91 }; 92 struct edge_info edgeInfo[x]; // expected-warning{{variable length arrays are a C99 feature}} 93 } 94 } 95 96 namespace rdar8020206 { 97 template<typename T> 98 void f(int i) { 99 const unsigned value = i; 100 int array[value * i]; // expected-warning 2{{variable length arrays are a C99 feature}} 101 } 102 103 template void f<int>(int); // expected-note{{instantiation of}} 104 } 105 106 namespace rdar8021385 { 107 typedef int my_int; 108 struct A { typedef int my_int; }; 109 template<typename T> 110 struct B { 111 typedef typename T::my_int my_int; 112 void f0() { 113 int M = 4; 114 my_int a[M]; // expected-warning{{variable length arrays are a C99 feature}} 115 } 116 }; 117 B<A> a; 118 } 119 120 namespace PR8209 { 121 void f(int n) { 122 typedef int vla_type[n]; // expected-warning{{variable length arrays are a C99 feature}} 123 (void)new vla_type; // expected-error{{variably}} 124 } 125 } 126 127 namespace rdar8733881 { // rdar://8733881 128 129 static const int k_cVal3 = (int)(1000*0.2f); 130 int f() { 131 // Ok, fold to a constant size array as an extension. 132 char rgch[k_cVal3] = {0}; 133 } 134 } 135 136 namespace PR11744 { 137 template<typename T> int f(int n) { 138 T arr[3][n]; // expected-warning 3 {{variable length arrays are a C99 feature}} 139 return 3; 140 } 141 int test = f<int>(0); // expected-note {{instantiation of}} 142 } 143