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/*
* infer.c -- generate definitions reflecting present hardware architecture
*
* Inspired by mail from Christian Hudon.
*/
#include <assert.h>
#include <stddef.h>
#include <stdio.h>
typedef struct {
char c;
double d;
} tstruct;
static long atdepth(int n) {
return n <= 1 ? (long)&n : atdepth(n - 1);
}
int main(int argc, char *argv[]) {
assert (-1 == (signed char)0xFF); /* chars must be 8 bits */
assert (sizeof(void*) == sizeof(long)); /* these must be the same */
assert (sizeof(int) >= 4); /* need 32-bit ints or better */
assert (sizeof(long) <= 8); /* but can't handle over 64 */
printf("/* generated by infer.c */\n");
printf("#define IntBits %d\n", (int) (8 * sizeof(int)));
printf("#define WordBits %d\n", (int) (8 * sizeof(void *)));
if (offsetof(tstruct, d) > sizeof(void *))
printf("#define Double\n");
if (atdepth(2) > atdepth(1))
printf("#define UpStack\n");
return 0;
}
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