gcc/testsuite/gcc.dg/flex-array-counted-by-8.c

   1  /* Testing the correct usage of attribute counted_by in c23, multiple
   2   * definitions of the same tag in same or different scopes.
   3  * { dg-do compile }
   4  * { dg-options "-std=c23" }
   5  */
   6
   7 /* Allowed redefinitions of the same struct in the same scope, with the
   8    same counted_by attribute.  */
   9 struct f {
  10   int b;
  11   int c;
  12   int a[] __attribute__ ((counted_by (b))); };
  13 struct f {
  14   int b;
  15   int c;
  16   int a[] __attribute__ ((counted_by (b))); };
  17 struct f {
  18   int b;
  19   int c;
  20   int a[]; }; /* { dg-error "redefinition of struct or union" } */
  21
  22 /* Error when the counted_by attribute is defined differently.  */
  23 struct f {
  24   int b;
  25   int c;
  26   int a[] __attribute__ ((counted_by (c))); }; /* { dg-error "redefinition of struct or union" } */
  27
  28 struct h {
  29   int b;
  30   int c;
  31   int a[] __attribute__ ((counted_by (b))); } p;
  32
  33 void test (void)
  34 {
  35   struct h {
  36   int b;
  37   int c;
  38   int a[] __attribute__ ((counted_by (b))); } x;
  39
  40   p = x;
  41 }
  42
  43 void test1 (void)
  44 {
  45   struct h {
  46   int b;
  47   int c;
  48   int a[] __attribute__ ((counted_by (c))); } y;
  49
  50   p = y;   /* { dg-error "incompatible types when assigning to type" } */
  51 }
  52
  53 struct nested_f {
  54   struct {
  55     union {
  56       int b;
  57       float f;
  58     };
  59     int n;
  60   };
  61   char c[] __attribute__ ((counted_by (b)));
  62 };
  63
  64 struct nested_f {
  65   struct {
  66     union {
  67       int b;
  68       float f;
  69     };
  70     int n;
  71   };
  72   char c[] __attribute__ ((counted_by (b)));
  73 };
  74
  75 struct nested_f {
  76   struct {
  77     union {
  78       int b;
  79       float f;
  80     };
  81     int n;
  82   };
  83   char c[] __attribute__ ((counted_by (n)));
  84 };  /* { dg-error "redefinition of struct or union" } */
  85
  86 struct nested_h {
  87   struct {
  88     union {
  89       int b;
  90       float f;
  91     };
  92     int n;
  93   };
  94   char c[] __attribute__ ((counted_by (b)));
  95 } nested_p;
  96
  97 void test_2 (void)
  98 {
  99 struct nested_h {
 100   struct {
 101     union {
 102       int b;
 103       float f;
 104     };
 105     int n;
 106   };
 107   char c[] __attribute__ ((counted_by (b)));
 108 } nested_x;
 109
 110  nested_p = nested_x;
 111 }
 112
 113 void test_3 (void)
 114 {
 115 struct nested_h {
 116   struct {
 117     union {
 118       int b;
 119       float f;
 120     };
 121     int n;
 122   };
 123   char c[] __attribute__ ((counted_by (n)));
 124 } nested_y;
 125
 126  nested_p = nested_y; /* { dg-error "incompatible types when assigning to type" } */
 127 }