Index: configure.ac
==================================================================
--- configure.ac
+++ configure.ac
@@ -404,11 +404,11 @@
 case "$host_os" in
 	darwin*)
 		AC_SUBST(LDFLAGS_REEXPORT, ["-Wl,-reexport-lobjfw"])
 		AS_IF([test x"$objc_runtime" = x"Apple runtime"], [
 			AC_SUBST(REEXPORT_LIBOBJC, ["-Wl,-reexport-lobjc"])
-			LDFLAGS="$LDFLAGS -Wl,-U,_CFRetain"
+			LDFLAGS="$LDFLAGS -Wl,-U,_NSFoundationVersionNumber"
 		])
 
 		AS_IF([test x"$objc_runtime" = x"ObjFW runtime"], [
 			AS_IF([test x"$exception_type" = x"DWARF"], [
 				LDFLAGS="$LDFLAGS -Wl,-U,___gxx_personality_v0"

Index: src/OFObject.m
==================================================================
--- src/OFObject.m
+++ src/OFObject.m
@@ -58,11 +58,11 @@
 #elif defined(OF_HAVE_THREADS)
 # import "threading.h"
 #endif
 
 #ifdef OF_APPLE_RUNTIME
-extern void* CFRetain(void*) __attribute__((__weak__));
+extern double *NSFoundationVersionNumber __attribute__((__weak__));
 #endif
 
 #if defined(OF_HAVE_FORWARDING_TARGET_FOR_SELECTOR)
 extern id of_forward(id, SEL, ...);
 extern struct stret of_forward_stret(id, SEL, ...);
@@ -218,18 +218,19 @@
 	objc_setUncaughtExceptionHandler(uncaughtExceptionHandler);
 #endif
 
 #if defined(OF_APPLE_RUNTIME)
 	/*
-	 * If the CFRetain symbol is defined, we are linked against
-	 * CoreFoundation. Since CoreFoundation sets its own forward handler
-	 * on load, we should not set ours, as this will break CoreFoundation.
+	 * If the NSFoundationVersionNumber symbol is defined, we are linked
+	 * against Foundation. Since CoreFoundation sets its own forward
+	 * handler on load, we should not set ours, as this will break
+	 * Foundation.
 	 *
 	 * Unfortunately, there is no way to check if a forward handler has
 	 * already been set, so this is the best we can do.
 	 */
-	if (&CFRetain == NULL)
+	if (&NSFoundationVersionNumber == NULL)
 		objc_setForwardHandler((void*)&of_forward,
 		    (void*)&of_forward_stret);
 #else
 	objc_setForwardHandler((IMP)&of_forward, (IMP)&of_forward_stret);
 #endif