#include <stdbool.h>

/** Define a proposition as likely true.
 * @param prop Proposition
**/
#undef likely
#ifdef __GNUC__
    #define likely(prop) \
        __builtin_expect((prop) ? true : false, true /* likely */)
#else
    #define likely(prop) \
        (prop)
#endif

/** Define a proposition as likely false.
 * @param prop Proposition
**/
#undef unlikely
#ifdef __GNUC__
    #define unlikely(prop) \
        __builtin_expect((prop) ? true : false, false /* unlikely */)
#else
    #define unlikely(prop) \
        (prop)
#endif

/** Define a variable as unused.
**/
#undef unused
#ifdef __GNUC__
    #define unused(variable) \
        variable __attribute__((unused))
#else
    #define unused(variable)
    #warning This compiler has no support for GCC attributes
#endif