1 // RUN: %clang_cc1 -fsyntax-only -fblocks -Wnullable-to-nonnull-conversion -Wno-nullability-declspec %s -verify
2 
3 #if __has_feature(nullability)
4 #else
5 #  error nullability feature should be defined
6 #endif
7 
8 typedef int * int_ptr;
9 
10 // Parse nullability type specifiers.
11 // This note requires C11.
12 #if __STDC_VERSION__ > 199901L
13 // expected-note@+2{{'_Nonnull' specified here}}
14 #endif
15 typedef int * _Nonnull nonnull_int_ptr;
16 typedef int * _Nullable nullable_int_ptr;
17 typedef int * _Null_unspecified null_unspecified_int_ptr;
18 
19 // Redundant nullability type specifiers.
20 typedef int * _Nonnull _Nonnull redundant_1; // expected-warning{{duplicate nullability specifier '_Nonnull'}}
21 
22 // Conflicting nullability type specifiers.
23 typedef int * _Nonnull _Nullable conflicting_1; // expected-error{{nullability specifier '_Nullable' conflicts with existing specifier '_Nonnull'}}
24 typedef int * _Null_unspecified _Nonnull conflicting_2; // expected-error{{nullability specifier '_Nonnull' conflicts with existing specifier '_Null_unspecified'}}
25 
26 // Redundant nullability specifiers via a typedef are okay.
27 typedef nonnull_int_ptr _Nonnull redundant_okay_1;
28 
29 // Conflicting nullability specifiers via a typedef are not.
30 // Some of these errors require C11.
31 #if __STDC_VERSION__ > 199901L
32 typedef nonnull_int_ptr _Nullable conflicting_2; // expected-error{{nullability specifier '_Nullable' conflicts with existing specifier '_Nonnull'}}
33 #endif
34 typedef nonnull_int_ptr nonnull_int_ptr_typedef;
35 #if __STDC_VERSION__ > 199901L
36 typedef nonnull_int_ptr_typedef _Nullable conflicting_2; // expected-error{{nullability specifier '_Nullable' conflicts with existing specifier '_Nonnull'}}
37 #endif
38 typedef nonnull_int_ptr_typedef nonnull_int_ptr_typedef_typedef;
39 typedef nonnull_int_ptr_typedef_typedef _Null_unspecified conflicting_3; // expected-error{{nullability specifier '_Null_unspecified' conflicts with existing specifier '_Nonnull'}}
40 
41 // Nullability applies to all pointer types.
42 typedef int (* _Nonnull function_pointer_type_1)(int, int);
43 typedef int (^ _Nonnull block_type_1)(int, int);
44 
45 // Nullability must be on a pointer type.
46 typedef int _Nonnull int_type_1; // expected-error{{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int'}}
47 
48 // Nullability can move out to a pointer/block pointer declarator
49 // (with a suppressed warning).
50 typedef _Nonnull int * nonnull_int_ptr_2;
51 typedef int _Nullable * nullable_int_ptr_2;
52 typedef _Nonnull int (* function_pointer_type_2)(int, int);
53 typedef _Nonnull int (^ block_type_2)(int, int);
54 typedef _Nonnull int * * _Nullable nonnull_int_ptr_ptr_1;
55 typedef _Nonnull int *(^ block_type_3)(int, int);
56 typedef _Nonnull int *(* function_pointer_type_3)(int, int);
57 typedef _Nonnull int_ptr (^ block_type_4)(int, int);
58 typedef _Nonnull int_ptr (* function_pointer_type_4)(int, int);
59 typedef void (* function_pointer_type_5)(int_ptr _Nonnull);
60 
61 void acceptFunctionPtr(_Nonnull int *(*)(void));
62 void acceptBlockPtr(_Nonnull int *(^)(void));
63 
testBlockFunctionPtrNullability()64 void testBlockFunctionPtrNullability() {
65   float *fp;
66   fp = (function_pointer_type_3)0; // expected-warning{{from 'function_pointer_type_3' (aka 'int * _Nonnull (*)(int, int)')}}
67   fp = (block_type_3)0; // expected-error{{from incompatible type 'block_type_3' (aka 'int * _Nonnull (^)(int, int)')}}
68   fp = (function_pointer_type_4)0; // expected-warning{{from 'function_pointer_type_4' (aka 'int * _Nonnull (*)(int, int)')}}
69   fp = (function_pointer_type_5)0; // expected-warning{{from 'function_pointer_type_5' (aka 'void (*)(int * _Nonnull)')}}
70   fp = (block_type_4)0; // expected-error{{from incompatible type 'block_type_4' (aka 'int_ptr  _Nonnull (^)(int, int)')}}
71 
72   acceptFunctionPtr(0); // no-warning
73   acceptBlockPtr(0); // no-warning
74 }
75 
76 // Moving nullability where it creates a conflict.
77 typedef _Nonnull int * _Nullable *  conflict_int_ptr_ptr_2; // expected-error{{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int'}}
78 
79 // Nullability is not part of the canonical type.
80 typedef int * _Nonnull ambiguous_int_ptr;
81 // Redefining a typedef is a C11 feature.
82 #if __STDC_VERSION__ > 199901L
83 typedef int * ambiguous_int_ptr;
84 typedef int * _Nullable ambiguous_int_ptr;
85 #endif
86 
87 // Printing of nullability.
88 float f;
89 int * _Nonnull ip_1 = &f; // expected-warning{{incompatible pointer types initializing 'int * _Nonnull' with an expression of type 'float *'}}
90 
91 // Check printing of nullability specifiers.
printing_nullability(void)92 void printing_nullability(void) {
93   int * _Nonnull iptr;
94   float *fptr = iptr; // expected-warning{{incompatible pointer types initializing 'float *' with an expression of type 'int * _Nonnull'}}
95 
96   int * * _Nonnull iptrptr;
97   float **fptrptr = iptrptr; // expected-warning{{incompatible pointer types initializing 'float **' with an expression of type 'int ** _Nonnull'}}
98 
99   int * _Nullable * _Nonnull iptrptr2;
100   float * *fptrptr2 = iptrptr2; // expected-warning{{incompatible pointer types initializing 'float **' with an expression of type 'int * _Nullable * _Nonnull'}}
101 }
102 
103 // Check passing null to a _Nonnull argument.
104 void accepts_nonnull_1(_Nonnull int *ptr);
105 void (*accepts_nonnull_2)(_Nonnull int *ptr);
106 void (^accepts_nonnull_3)(_Nonnull int *ptr);
107 
test_accepts_nonnull_null_pointer_literal()108 void test_accepts_nonnull_null_pointer_literal() {
109   accepts_nonnull_1(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
110   accepts_nonnull_2(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
111   accepts_nonnull_3(0); // expected-warning{{null passed to a callee that requires a non-null argument}}
112 }
113 
114 // Check returning nil from a _Nonnull-returning function.
returns_int_ptr(int x)115 _Nonnull int *returns_int_ptr(int x) {
116   if (x) {
117     return 0; // expected-warning{{null returned from function that requires a non-null return value}}
118   }
119 
120   return (_Nonnull int *)0;
121 }
122 
123 // Check nullable-to-nonnull conversions.
nullable_to_nonnull(_Nullable int * ptr)124 void nullable_to_nonnull(_Nullable int *ptr) {
125   int *a = ptr; // okay
126   _Nonnull int *b = ptr; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
127   b = ptr; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
128 
129   accepts_nonnull_1(ptr); // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
130 }
131 
132 // Check nullability of conditional expressions.
conditional_expr(int c)133 void conditional_expr(int c) {
134   int * _Nonnull p;
135   int * _Nonnull nonnullP;
136   int * _Nullable nullableP;
137   int * _Null_unspecified unspecifiedP;
138   int *noneP;
139 
140   p = c ? nonnullP : nonnullP;
141   p = c ? nonnullP : nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
142   p = c ? nonnullP : unspecifiedP;
143   p = c ? nonnullP : noneP;
144   p = c ? nullableP : nonnullP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
145   p = c ? nullableP : nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
146   p = c ? nullableP : unspecifiedP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
147   p = c ? nullableP : noneP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
148   p = c ? unspecifiedP : nonnullP;
149   p = c ? unspecifiedP : nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
150   p = c ? unspecifiedP : unspecifiedP;
151   p = c ? unspecifiedP : noneP;
152   p = c ? noneP : nonnullP;
153   p = c ? noneP : nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
154   p = c ? noneP : unspecifiedP;
155   p = c ? noneP : noneP;
156 
157   // Check that we don't remove all sugar when creating a new QualType for the
158   // conditional expression.
159   typedef int *IntP;
160   typedef IntP _Nonnull NonnullIntP0;
161   typedef NonnullIntP0 _Nonnull NonnullIntP1;
162   typedef IntP _Nullable NullableIntP0;
163   typedef NullableIntP0 _Nullable NullableIntP1;
164   NonnullIntP1 nonnullP2;
165   NullableIntP1 nullableP2;
166 
167   p = c ? nonnullP2 : nonnullP2;
168   p = c ? nonnullP2 : nullableP2; // expected-warning{{implicit conversion from nullable pointer 'IntP _Nullable' (aka 'int *') to non-nullable pointer type 'int * _Nonnull'}}
169   p = c ? nullableP2 : nonnullP2; // expected-warning{{implicit conversion from nullable pointer 'NullableIntP1' (aka 'int *') to non-nullable pointer type 'int * _Nonnull'}}
170   p = c ? nullableP2 : nullableP2; // expected-warning{{implicit conversion from nullable pointer 'NullableIntP1' (aka 'int *') to non-nullable pointer type 'int * _Nonnull'}}
171 }
172 
173 // Check nullability of binary conditional expressions.
binary_conditional_expr()174 void binary_conditional_expr() {
175   int * _Nonnull p;
176   int * _Nonnull nonnullP;
177   int * _Nullable nullableP;
178   int * _Null_unspecified unspecifiedP;
179   int *noneP;
180 
181   p = nonnullP ?: nonnullP;
182   p = nonnullP ?: nullableP;
183   p = nonnullP ?: unspecifiedP;
184   p = nonnullP ?: noneP;
185   p = nullableP ?: nonnullP;
186   p = nullableP ?: nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
187   p = nullableP ?: unspecifiedP;
188   p = nullableP ?: noneP;
189   p = unspecifiedP ?: nonnullP;
190   p = unspecifiedP ?: nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
191   p = unspecifiedP ?: unspecifiedP;
192   p = unspecifiedP ?: noneP;
193   p = noneP ?: nonnullP;
194   p = noneP ?: nullableP; // expected-warning{{implicit conversion from nullable pointer 'int * _Nullable' to non-nullable pointer type 'int * _Nonnull'}}
195   p = noneP ?: unspecifiedP;
196   p = noneP ?: noneP;
197 }
198 
199 extern int GLOBAL_LENGTH;
200 
201 // Nullability can appear on arrays when the arrays are in parameter lists.
202 void arrays(int ints[_Nonnull],
203             void *ptrs[_Nullable],
204             void **nestedPtrs[_Nullable],
205             void * _Null_unspecified * _Nonnull nestedPtrs2[_Nullable],
206             int fixedSize[_Nonnull 2],
207             int staticSize[_Nonnull static 2],
208             int staticSize2[static _Nonnull 2],
209             int starSize[_Nonnull *],
210             int vla[_Nonnull GLOBAL_LENGTH],
211             void ** _Nullable reference);
testDecayedType()212 void testDecayedType() {
213   int produceAnErrorMessage = arrays; // expected-warning {{incompatible pointer to integer conversion initializing 'int' with an expression of type 'void (int * _Nonnull, void ** _Nullable, void *** _Nullable, void * _Null_unspecified * _Nonnull * _Nullable, int * _Nonnull, int * _Nonnull, int * _Nonnull, int * _Nonnull, int * _Nonnull, void ** _Nullable)'}}
214 }
215 
216 int notInFunction[_Nullable 3]; // expected-error {{nullability specifier '_Nullable' cannot be applied to non-pointer type 'int [3]'}}
217 
nestedArrays(int x[5][_Nonnull1])218 void nestedArrays(int x[5][_Nonnull 1]) {} // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int [1]'}}
nestedArrays2(int x[5][_Nonnull1][2])219 void nestedArrays2(int x[5][_Nonnull 1][2]) {} // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int [1][2]'}}
nestedArraysOK(int x[_Nonnull5][1])220 void nestedArraysOK(int x[_Nonnull 5][1]) {} // ok
221 
222 void nullabilityOnBase(_Nonnull int x[1], // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int'}}
223                        int _Nonnull y[1]); // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int'}}
224 
225 typedef int INTS[4];
226 typedef int BAD_INTS[_Nonnull 4]; // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int [4]'}}
227 
228 void typedefTest(INTS _Nonnull x,
229                  _Nonnull INTS xx,
230                  INTS _Nonnull y[2], // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'INTS' (aka 'int [4]')}}
231                  INTS z[_Nonnull 2]);
232 
233 INTS _Nonnull x; // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'INTS' (aka 'int [4]')}}
234 _Nonnull INTS x; // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'INTS' (aka 'int [4]')}}
235 
arraysInBlocks()236 void arraysInBlocks() {
237   typedef int INTS[4];
238   void (^simple)(int [_Nonnull 2]) = ^(int x[_Nonnull 2]) {};
239   simple(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
240   void (^nested)(void *_Nullable x[_Nonnull 2]) = ^(void *_Nullable x[_Nonnull 2]) {};
241   nested(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
242   void (^nestedBad)(int x[2][_Nonnull 2]) = // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int [2]'}}
243     ^(int x[2][_Nonnull 2]) {}; // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'int [2]'}}
244 
245   void (^withTypedef)(INTS _Nonnull) = ^(INTS _Nonnull x) {};
246   withTypedef(0); // expected-warning {{null passed to a callee that requires a non-null argument}}
247   void (^withTypedefBad)(INTS _Nonnull [2]) = // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'INTS' (aka 'int [4]')}}
248       ^(INTS _Nonnull x[2]) {}; // expected-error {{nullability specifier '_Nonnull' cannot be applied to non-pointer type 'INTS' (aka 'int [4]')}}
249 }
250