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
|
/* EXPECT:
-1155497588
*/
typedef unsigned long long uvlong;
int fn1(uvlong p_9) {
/* extract from ldrgen seed=637312671 */
uvlong v_73, q;
if (p_9) {
v_73 = 909910719;
}
q = (uvlong)p_9 / ((v_73 - 572547313ull) + 445ull);
return q;
}
/* Excerpt from linux/kernel.h */
/*
* This returns a constant expression while determining if an argument is
* a constant expression, most importantly without evaluating the argument.
* Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de>
*/
#define __is_constexpr(x) \
(sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8)))
_Static_assert(__is_constexpr(5 &&(1<<3) || 0/0), "");
_Static_assert(!__is_constexpr(5/0), "");
_Static_assert(!__is_constexpr(fn1(0)), "");
#include <stddef.h>
#include <stdint.h>
struct foo { int *a, b[2]; };
static intptr_t offst[] = {
(long)((struct foo *)0)->b,
(long)&((struct foo *)0)->a,
(long)&((struct foo *)0)->b[1],
(intptr_t)("12" - 5)
};
extern int printf(const char *, ...);
#include <assert.h>
int main() {
printf("%d\n", fn1(-77ull));
assert(offst[0] == offsetof(struct foo, b));
assert(offst[1] == offsetof(struct foo, a));
assert(offst[2] == offsetof(struct foo, b[1]));
}
|
