blob: 7bc6d18e24f9dab72ee27ea6f7b58437bbef458c [file] [log] [blame]
//===--- union2.c --- Test Cases for Bit Accurate Types -------------------===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// This is a test for union type. By assigning values to different
// fields, we can check whether the assignment is correctly performed.
// Note: In the current implementation, a 9-bit data will also occupy
// 2 bytes. So for this example, storing value to the 9-bit field will
// change the two bytes of the memory.
#include <stdio.h>
typedef int __attribute__ ((bitwidth(9))) int9;
typedef int __attribute__ ((bitwidth(31))) int31;
typedef union {short i; int9 i9; int31 i31;} myUnion;
typedef struct myStruct {int9* ptr; short i;} myStruct;
myStruct test(myUnion *u)
myStruct x;
int9* ptr;
u->i31 = -1;
u->i = 0x0;
ptr = &(u->i9);
*ptr= -1;
x.ptr = ptr;
x.i = u->i;
return x;
static myUnion uu;
int main()
myStruct s = test(&uu);
printf("uu.i = %hd\n", uu.i);
printf("uu.i9 = %d\n", (int)uu.i9);
printf("uu.i31= %d\n", uu.i31);
if(s.i == 0x0)
printf("error: s.i=%x\n", s.i);
return 0;