1 /* CC0 (Public domain) - see LICENSE file for details */
2 #ifndef CCAN_ARRAY_SIZE_H
3 #define CCAN_ARRAY_SIZE_H
5 #include <ccan/build_assert/build_assert.h>
8 * ARRAY_SIZE - get the number of elements in a visible array
9 * @arr: the array whose size you want.
11 * This does not work on pointers, or arrays declared as [], or
12 * function parameters. With correct compiler support, such usage
13 * will cause a build error (see build_assert).
15 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + _array_size_chk(arr))
17 #if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
18 /* Two gcc extensions.
19 * &a[0] degrades to a pointer: a different type from an array */
20 #define _array_size_chk(arr) \
21 BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(typeof(arr), \
24 #define _array_size_chk(arr) 0
26 #endif /* CCAN_ALIGNOF_H */