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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

#pragma pack(1)  // tells compiler not to add padding to struct object fields.

typedef union {
    int as_int;      // 4 bytes on our platform
    char* as_string; // 8 bytes on our platform
} IntOrString;       // 8 bytes on our platform (max size of its fields)

int main(int argc, char* argv[]) {
    IntOrString int_union_object = { .as_int = 32768 };
    printf("sizeof(int_union_object) == %zd\n", sizeof(int_union_object));

    IntOrString string_union_object = { .as_string = "" };
    printf("sizeof(string_union_object) == %zd\n", sizeof(string_union_object));

    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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