bitfield-layout.c revision a5728872c7702ddd09537c95bc3cbd20e1f2fb09
1// RUN: %clang_cc1 %s -fsyntax-only -verify -triple=i686-apple-darwin9 2 3#define CHECK_SIZE(kind, name, size) extern int name##1[sizeof(kind name) == size ? 1 : -1]; 4#define CHECK_ALIGN(kind, name, size) extern int name##2[__alignof(kind name) == size ? 1 : -1]; 5 6// Zero-width bit-fields 7struct a {char x; int : 0; char y;}; 8CHECK_SIZE(struct, a, 5) 9CHECK_ALIGN(struct, a, 1) 10 11union b {char x; int : 0; char y;}; 12CHECK_SIZE(union, b, 1) 13CHECK_ALIGN(union, b, 1) 14 15// Unnamed bit-field align 16struct c {char x; int : 20;}; 17CHECK_SIZE(struct, c, 4) 18CHECK_ALIGN(struct, c, 1) 19 20union d {char x; int : 20;}; 21CHECK_SIZE(union, d, 3) 22CHECK_ALIGN(union, d, 1) 23 24// Bit-field packing 25struct __attribute__((packed)) e {int x : 4, y : 30, z : 30;}; 26CHECK_SIZE(struct, e, 8) 27CHECK_ALIGN(struct, e, 1) 28 29// Alignment on bit-fields 30struct f {__attribute((aligned(8))) int x : 30, y : 30, z : 30;}; 31CHECK_SIZE(struct, f, 24) 32CHECK_ALIGN(struct, f, 8) 33