117 lines
2.6 KiB
C
Executable File
117 lines
2.6 KiB
C
Executable File
#include <stdio.h>
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#include <stdbool.h>
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/*
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* found in the good old Usenet
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*/
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/* The expected sizes in these comments assime a 64-bit machine */
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struct foo1 {
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char *p;
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char c;
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long x;
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};
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struct foo2 {
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char c; /* 1 byte */
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char pad[7]; /* 7 bytes */
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char *p; /* 8 bytes */
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long x; /* 8 bytes */
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};
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struct foo3 {
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char *p; /* 8 bytes */
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char c; /* 1 byte */
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};
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struct foo4 {
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short s; /* 2 bytes */
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char c; /* 1 byte */
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};
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struct foo5 {
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char c;
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struct foo5_inner {
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char *p;
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short x;
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} inner;
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};
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struct foo6 {
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short s;
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char c;
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int flip:1;
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int nybble:4;
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int septet:7;
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};
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struct foo7 {
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int bigfield:31;
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int littlefield:1;
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};
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struct foo8 {
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int bigfield1:31;
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int littlefield1:1;
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int bigfield2:31;
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int littlefield2:1;
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};
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struct foo9 {
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int bigfield1:31;
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int bigfield2:31;
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int littlefield1:1;
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int littlefield2:1;
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};
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struct foo10 {
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char c;
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struct foo10 *p;
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short x;
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};
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struct foo11 {
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struct foo11 *p;
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short x;
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char c;
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};
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struct foo12 {
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struct foo12_inner {
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char *p;
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short x;
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} inner;
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char c;
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};
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int main(int argc, char *argv[])
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{
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printf("sizeof(char *) = %zu\n", sizeof(char *));
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printf("sizeof(long) = %zu\n", sizeof(long));
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printf("sizeof(int) = %zu\n", sizeof(int));
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printf("sizeof(short) = %zu\n", sizeof(short));
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printf("sizeof(char) = %zu\n", sizeof(char));
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printf("sizeof(float) = %zu\n", sizeof(float));
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printf("sizeof(double) = %zu\n", sizeof(double));
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printf("sizeof(struct foo1) = %zu\n", sizeof(struct foo1));
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printf("sizeof(struct foo2) = %zu\n", sizeof(struct foo2));
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printf("sizeof(struct foo3) = %zu\n", sizeof(struct foo3));
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printf("sizeof(struct foo4) = %zu\n", sizeof(struct foo4));
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printf("sizeof(struct foo5) = %zu\n", sizeof(struct foo5));
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printf("sizeof(struct foo6) = %zu\n", sizeof(struct foo6));
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printf("sizeof(struct foo7) = %zu\n", sizeof(struct foo7));
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printf("sizeof(struct foo8) = %zu\n", sizeof(struct foo8));
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printf("sizeof(struct foo9) = %zu\n", sizeof(struct foo9));
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printf("sizeof(struct foo10) = %zu\n", sizeof(struct foo10));
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printf("sizeof(struct foo11) = %zu\n", sizeof(struct foo11));
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printf("sizeof(struct foo12) = %zu\n", sizeof(struct foo12));
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if (sizeof(struct foo3) == 16) {
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puts("This looks like a 64-bit machine.");
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} else if (sizeof(struct foo3) == 6) {
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puts("This looks like a 32-bit machine.");
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}
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}
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