1 #ifndef CCAN_ARRAY_SIZE_H
2 #define CCAN_ARRAY_SIZE_H
4 #include <ccan/build_assert/build_assert.h>
7 * ARRAY_SIZE - get the number of elements in a visible array
8 * @arr: the array whose size you want.
10 * This does not work on pointers, or arrays declared as [], or
11 * function parameters. With correct compiler support, such usage
12 * will cause a build error (see build_assert).
14 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + _array_size_chk(arr))
16 #if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
17 /* Two gcc extensions.
18 * &a[0] degrades to a pointer: a different type from an array */
19 #define _array_size_chk(arr) \
20 EXPR_BUILD_ASSERT(!__builtin_types_compatible_p(typeof(arr), \
23 #define _array_size_chk(arr) 0
25 #endif /* CCAN_ALIGNOF_H */