Index: src/OFObject.m
==================================================================
--- src/OFObject.m
+++ src/OFObject.m
@@ -58,11 +58,12 @@
 #elif defined(OF_HAVE_THREADS)
 # import "threading.h"
 #endif
 
 #ifdef OF_APPLE_RUNTIME
-extern double *NSFoundationVersionNumber __attribute__((__weak__));
+static double NSFoundationVersionNumber
+    OF_WEAK_REF("NSFoundationVersionNumber");
 #endif
 
 #if defined(OF_HAVE_FORWARDING_TARGET_FOR_SELECTOR)
 extern id of_forward(id, SEL, ...);
 extern struct stret of_forward_stret(id, SEL, ...);

Index: src/macros.h
==================================================================
--- src/macros.h
+++ src/macros.h
@@ -68,16 +68,18 @@
 # define OF_INLINE inline __attribute__((__always_inline__))
 # define OF_LIKELY(cond) (__builtin_expect(!!(cond), 1))
 # define OF_UNLIKELY(cond) (__builtin_expect(!!(cond), 0))
 # define OF_CONST_FUNC __attribute__((__const__))
 # define OF_NO_RETURN_FUNC __attribute__((__noreturn__))
+# define OF_WEAK_REF(sym) __attribute__((__weakref__(sym)))
 #else
 # define OF_INLINE inline
 # define OF_LIKELY(cond) cond
 # define OF_UNLIKELY(cond) cond
 # define OF_CONST_FUNC
 # define OF_NO_RETURN_FUNC
+# define OF_WEAK_REF(sym)
 #endif
 
 #ifdef OF_BIG_ENDIAN
 # define OF_BYTE_ORDER_NATIVE OF_BYTE_ORDER_BIG_ENDIAN
 #else

Index: src/runtime/exception.m
==================================================================
--- src/runtime/exception.m
+++ src/runtime/exception.m
@@ -27,15 +27,15 @@
 #import "runtime-private.h"
 
 #import "macros.h"
 
 #if defined(HAVE_DWARF_EXCEPTIONS)
-# define PERSONALITY	 __gnu_objc_personality_v0
-# define CXX_PERSONALITY __gxx_personality_v0
+# define PERSONALITY __gnu_objc_personality_v0
+# define CXX_PERSONALITY_STR "__gxx_personality_v0"
 #elif defined(HAVE_SJLJ_EXCEPTIONS)
-# define PERSONALITY	 __gnu_objc_personality_sj0
-# define CXX_PERSONALITY __gxx_personality_sj0
+# define PERSONALITY __gnu_objc_personality_sj0
+# define CXX_PERSONALITY_STR "__gxx_personality_sj0"
 # define _Unwind_RaiseException _Unwind_SjLj_RaiseException
 # define __builtin_eh_return_data_regno(i) (i)
 #elif defined(HAVE_SEH_EXCEPTIONS)
 # define PERSONALITY	 gnu_objc_personality
 #else
@@ -213,11 +213,11 @@
 	_Unwind_SetGR(ctx, 15, (value | thumb));
 }
 #endif
 
 #ifdef CXX_PERSONALITY
-extern PERSONALITY_FUNC(CXX_PERSONALITY) __attribute__((__weak__));
+static PERSONALITY_FUNC(cxx_personality) OF_WEAK_REF(CXX_PERSONALITY_STR);
 #endif
 
 #ifdef HAVE_SEH_EXCEPTIONS
 extern EXCEPTION_DISPOSITION _GCC_specific_handler(PEXCEPTION_RECORD, void*,
     PCONTEXT, PDISPATCHER_CONTEXT, _Unwind_Reason_Code(*)(int, int, uint64_t,
@@ -568,12 +568,12 @@
 	if (foreign) {
 		switch (ex_class) {
 #ifdef CXX_PERSONALITY
 		case GNUCCXX0_EXCEPTION_CLASS:
 		case CLNGCXX0_EXCEPTION_CLASS:
-			if (CXX_PERSONALITY != NULL)
-				return CALL_PERSONALITY(CXX_PERSONALITY);
+			if (cxx_personality != NULL)
+				return CALL_PERSONALITY(cxx_personality);
 			break;
 #endif
 		}
 
 		/*