gcc/testsuite/g++.dg/ext/flexary.h

   1 // Definitions of helper macros for tests of flexible array members.
   2
   3 #if __cplusplus < 201102L
   4 #  define _CAT(x, y)  x ## y
   5 #  define CAT(x, y)  _CAT (x, y)
   6
   7 // Generate a struct with a unique name containing a bitfield
   8 // of size that must evaluate to a non-zero value, otherwise
   9 // generate a compiler error.
  10 #  define ASSERT(expr)                                                  \
  11   struct CAT (FAM_Assert, __LINE__) { unsigned asrt: 0 != (expr); }
  12 #else
  13 // In C++ 11 and beyond, use static_assert.
  14 # define ASSERT(expr) static_assert (expr, #expr)
  15 #endif
  16
  17 // Macro to verify that a flexible array member is allocated
  18 // at the very end of the containing struct.
  19 #define ASSERT_AT_END(T, m)                             \
  20   ASSERT (__builtin_offsetof (T, m) == sizeof (T))
  21
  22 typedef __SIZE_TYPE__ size_t;