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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: 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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