blob: b6e5c22d68d5942bd3fdb98f25b5bb2ad76f44f0 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
/* gcc-style "aligned" and "section" attributes */
/* Caveat: some C standard libraries, when preprocessed with -U__GNUC__,
#define away __attribute__, so we use __attribute in the following. */
#include <stdio.h>
/* Alignment */
char filler1 = 1;
__attribute((__aligned__(1<<4))) int a = 1234;
char filler2 = 1;
__attribute((__aligned__(8))) char b = 'b';
/* Sections */
__attribute((__section__("mydata"))) int c = 78;
char filler3 = 1;
__attribute((__section__("mydata"))) int d = 90;
__attribute((__section__("myconst"))) const int e = 12;
const char filler4 = 1;
__attribute((__section__("myconst"))) const int f = 34;
__attribute((__section__("mycode"))) int myfunc(int x) { return x + 1; }
/* Alignment with typedefs and structs */
struct __attribute((__aligned__(8))) mystruct { char c1, c2; };
char filler5 = 1;
struct mystruct u;
typedef __attribute((__aligned__(8))) int myint;
char filler6 = 1;
myint v;
/* Test harness */
int main()
{
printf("Address of a = %u mod 16\n", ((unsigned int) &a) & 0xF);
printf("Address of b = %u mod 8\n", ((unsigned int) &b) & 0x7);
printf("Delta d - c = %u\n", ((unsigned int) &d) - ((unsigned int) &c));
printf("Delta f - e = %u\n", ((unsigned int) &f) - ((unsigned int) &e));
printf("Address of u = %u mod 8\n", ((unsigned int) &u) & 0x7);
printf("Address of v = %u mod 8\n", ((unsigned int) &v) & 0x7);
return 0;
}
|
