ObjFW  Check-in [26f6bd3396]

				    PTHREAD_MUTEX_RECURSIVE);
			], [
				AC_DEFINE(OF_HAVE_RECURSIVE_PTHREAD_MUTEXES, 1,
					[If pthread mutexes can be recursive])
			])

			AC_CHECK_FUNC(pthread_spin_lock, [
				have_spinlocks="yes"
				AC_DEFINE(OF_HAVE_PTHREAD_SPINLOCKS, 1,
					[Whether we have pthread spinlocks])
			])

			AC_CHECK_FUNC(sched_yield, [
				AC_DEFINE(OF_HAVE_SCHED_YIELD, 1,
					[Whether we have sched_yield()])

	printf "  ** To get optimal performance and be able to use all "
	echo "features, you should "
	echo "  ** install Clang >= 3.2."
	echo
])

AS_IF([test x"$enable_threads" != x"no" -a x"$atomic_ops" = x"none" \
    -a x"ac_cv_func_pthread_spin_lock" != x"yes"], [
    -a x"$have_spinlocks" != x"yes"], [
	echo
	printf "  ** Warning: You have enabled threads, but neither atomic "
	echo "operations nor"
	printf "  ** spinlocks are available. Expect *very* poor performance, "
	echo "as a mutex will"
	printf "  ** be locked for every retain and release! If you don't "
	echo "need threads, try"
	echo "  ** --disable-threads to work around this problem."
	echo
])

#if __has_feature(objc_arc)
# define OBJC_UNSAFE_UNRETAINED __unsafe_unretained
#else
# define OBJC_UNSAFE_UNRETAINED
#endif

typedef struct objc_class *Class;
typedef struct objc_object *id;
typedef const struct objc_selector *SEL;
typedef struct objc_class* Class;
typedef struct objc_object* id;
typedef const struct objc_selector* SEL;
typedef signed char BOOL;
typedef id (*IMP)(id, SEL, ...);

struct objc_class {
	Class isa;
	Class superclass;
	const char *name;

	struct objc_protocol_list *protocols;
	void *gc_object_type;
	unsigned long abi_version;
	void *ivar_offsets;
	struct objc_property_list *properties;
};

enum objc_abi_class_info {
enum objc_class_info {
	OBJC_CLASS_INFO_CLASS	    = 0x001,
	OBJC_CLASS_INFO_METACLASS   = 0x002,
	OBJC_CLASS_INFO_NEW_ABI	    = 0x010,
	OBJC_CLASS_INFO_SETUP	    = 0x100,
	OBJC_CLASS_INFO_LOADED	    = 0x200,
	OBJC_CLASS_INFO_DTABLE	    = 0x400,
	OBJC_CLASS_INFO_INITIALIZED = 0x800