xref: /llvm-project/clang/test/Sema/attr-counted-by-vla.c (revision 876ee11eeeb2b6a7ccfefea00265b4bfd5f9b6dd)
1 // RUN: %clang_cc1 -fsyntax-only -verify=expected,immediate %s
2 // RUN: %clang_cc1 -fsyntax-only -fexperimental-late-parse-attributes %s -verify=expected,late
3 
4 #define __counted_by(f)  __attribute__((counted_by(f)))
5 
6 struct bar;
7 
8 struct not_found {
9   int count;
10   struct bar *fam[] __counted_by(bork); // expected-error {{use of undeclared identifier 'bork'}}
11 };
12 
13 struct no_found_count_not_in_substruct {
14   unsigned long flags;
15   unsigned char count; // expected-note {{'count' declared here}}
16   struct A {
17     int dummy;
18     int array[] __counted_by(count); // expected-error {{'counted_by' field 'count' isn't within the same struct as the annotated flexible array}}
19   } a;
20 };
21 
22 struct not_found_count_not_in_unnamed_substruct {
23   unsigned char count; // expected-note {{'count' declared here}}
24   struct {
25     int dummy;
26     int array[] __counted_by(count); // expected-error {{'counted_by' field 'count' isn't within the same struct as the annotated flexible array}}
27   } a;
28 };
29 
30 struct not_found_count_not_in_unnamed_substruct_2 {
31   struct {
32     unsigned char count; // expected-note {{'count' declared here}}
33   };
34   struct {
35     int dummy;
36     int array[] __counted_by(count); // expected-error {{'counted_by' field 'count' isn't within the same struct as the annotated flexible array}}
37   } a;
38 };
39 
40 struct not_found_count_in_other_unnamed_substruct {
41   struct {
42     unsigned char count;
43   } a1;
44 
45   struct {
46     int dummy;
47     int array[] __counted_by(count); // expected-error {{use of undeclared identifier 'count'}}
48   };
49 };
50 
51 struct not_found_count_in_other_substruct {
52   struct _a1 {
53     unsigned char count;
54   } a1;
55 
56   struct {
57     int dummy;
58     int array[] __counted_by(count); // expected-error {{use of undeclared identifier 'count'}}
59   };
60 };
61 
62 struct not_found_count_in_other_substruct_2 {
63   struct _a2 {
64     unsigned char count;
65   } a2;
66 
67   int array[] __counted_by(count); // expected-error {{use of undeclared identifier 'count'}}
68 };
69 
70 struct not_found_suggest {
71   int bork;
72   struct bar *fam[] __counted_by(blork); // expected-error {{use of undeclared identifier 'blork'}}
73 };
74 
75 int global; // expected-note {{'global' declared here}}
76 
77 struct found_outside_of_struct {
78   int bork;
79   struct bar *fam[] __counted_by(global); // expected-error {{field 'global' in 'counted_by' not inside structure}}
80 };
81 
82 struct self_referrential {
83   int bork;
84   // immediate-error@+2{{use of undeclared identifier 'self'}}
85   // late-error@+1{{'counted_by' requires a non-boolean integer type argument}}
86   struct bar *self[] __counted_by(self);
87 };
88 
89 struct non_int_count {
90   double dbl_count;
91   struct bar *fam[] __counted_by(dbl_count); // expected-error {{'counted_by' requires a non-boolean integer type argument}}
92 };
93 
94 struct array_of_ints_count {
95   int integers[2];
96   struct bar *fam[] __counted_by(integers); // expected-error {{'counted_by' requires a non-boolean integer type argument}}
97 };
98 
99 struct not_a_fam {
100   int count;
101   // expected-error@+1{{'counted_by' cannot be applied to a pointer with pointee of unknown size because 'struct bar' is an incomplete type}}
102   struct bar *non_fam __counted_by(count);
103 };
104 
105 struct not_a_c99_fam {
106   int count;
107   struct bar *non_c99_fam[0] __counted_by(count); // expected-error {{'counted_by' on arrays only applies to C99 flexible array members}}
108 };
109 
110 struct annotated_with_anon_struct {
111   unsigned long flags;
112   struct {
113     unsigned char count;
114     int array[] __counted_by(crount); // expected-error {{use of undeclared identifier 'crount'}}
115   };
116 };
117 
118 //==============================================================================
119 // __counted_by on a struct VLA with element type that has unknown size
120 //==============================================================================
121 
122 struct size_unknown; // expected-note 2{{forward declaration of 'struct size_unknown'}}
123 struct on_member_arr_incomplete_ty_ty_pos {
124   int count;
125   // expected-error@+2{{'counted_by' only applies to pointers or C99 flexible array members}}
126   // expected-error@+1{{array has incomplete element type 'struct size_unknown'}}
127   struct size_unknown buf[] __counted_by(count);
128 };
129 
130 struct on_member_arr_incomplete_const_ty_ty_pos {
131   int count;
132   // expected-error@+2{{'counted_by' only applies to pointers or C99 flexible array members}}
133   // expected-error@+1{{array has incomplete element type 'const struct size_unknown'}}
134   const struct size_unknown buf[] __counted_by(count);
135 };
136 
137 struct on_member_arr_void_ty_ty_pos {
138   int count;
139   // expected-error@+2{{'counted_by' only applies to pointers or C99 flexible array members}}
140   // expected-error@+1{{array has incomplete element type 'void'}}
141   void buf[] __counted_by(count);
142 };
143 
144 typedef void(fn_ty)(int);
145 
146 struct on_member_arr_fn_ptr_ty {
147   int count;
148   // An Array of function pointers is allowed
149   fn_ty* buf[] __counted_by(count);
150 };
151 
152 struct on_member_arr_fn_ty {
153   int count;
154   // An array of functions is not allowed.
155   // expected-error@+2{{'counted_by' only applies to pointers or C99 flexible array members}}
156   // expected-error@+1{{'buf' declared as array of functions of type 'fn_ty' (aka 'void (int)')}}
157   fn_ty buf[] __counted_by(count);
158 };
159 
160 
161 // `buffer_of_structs_with_unnannotated_vla`,
162 // `buffer_of_structs_with_annotated_vla`, and
163 // `buffer_of_const_structs_with_annotated_vla` are currently prevented because
164 // computing the size of `Arr` at runtime would require an O(N) walk of `Arr`
165 // elements to take into account the length of the VLA in each struct instance.
166 
167 struct has_unannotated_VLA {
168   int count;
169   char buffer[];
170 };
171 
172 struct has_annotated_VLA {
173   int count;
174   char buffer[] __counted_by(count);
175 };
176 
177 struct buffer_of_structs_with_unnannotated_vla {
178   int count;
179   // Treating this as a warning is a temporary fix for existing attribute adopters. It **SHOULD BE AN ERROR**.
180   // expected-warning@+1{{'counted_by' should not be applied to an array with element of unknown size because 'struct has_unannotated_VLA' is a struct type with a flexible array member. This will be an error in a future compiler version}}
181   struct has_unannotated_VLA Arr[] __counted_by(count);
182 };
183 
184 
185 struct buffer_of_structs_with_annotated_vla {
186   int count;
187   // Treating this as a warning is a temporary fix for existing attribute adopters. It **SHOULD BE AN ERROR**.
188   // expected-warning@+1{{'counted_by' should not be applied to an array with element of unknown size because 'struct has_annotated_VLA' is a struct type with a flexible array member. This will be an error in a future compiler version}}
189   struct has_annotated_VLA Arr[] __counted_by(count);
190 };
191 
192 struct buffer_of_const_structs_with_annotated_vla {
193   int count;
194   // Treating this as a warning is a temporary fix for existing attribute adopters. It **SHOULD BE AN ERROR**.
195   // Make sure the `const` qualifier is printed when printing the element type.
196   // expected-warning@+1{{'counted_by' should not be applied to an array with element of unknown size because 'const struct has_annotated_VLA' is a struct type with a flexible array member. This will be an error in a future compiler version}}
197   const struct has_annotated_VLA Arr[] __counted_by(count);
198 };
199 
200