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#include <stdio.h>
#include <string.h>
#include "config.h"
/**
* build_assert - routines for build-time assertions
*
* This code provides routines which will cause compilation to fail should some
* assertion be untrue: such failures are preferable to run-time assertions,
* but much more limited since they can only depends on compile-time constants.
*
* These assertions are most useful when two parts of the code must be kept in
* sync: it is better to avoid such cases if possible, but seconds best is to
* detect invalid changes at build time.
*
* For example, a tricky piece of code might rely on a certain element being at
* the start of the structure. To ensure that future changes don't break it,
* you would catch such changes in your code like so:
*
* Example:
* #include <stddef.h>
* #include <ccan/build_assert/build_assert.h>
*
* struct foo {
* char string[5];
* int x;
* };
*
* static char *foo_string(struct foo *foo)
* {
* // This trick requires that the string be first in the structure
* BUILD_ASSERT(offsetof(struct foo, string) == 0);
* return (char *)foo;
* }
*
* License: CC0 (Public domain)
* Author: Rusty Russell <rusty@rustcorp.com.au>
*/
int main(int argc, char *argv[])
{
if (argc != 2)
return 1;
if (strcmp(argv[1], "depends") == 0)
/* Nothing. */
return 0;
return 1;
}
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