@@ -16,11 +16,13 @@
 
 #import <Foundation/NSDictionary.h>
 
 #import "NSBridging.h"
 
+#ifdef NS_ASSUME_NONNULL_BEGIN
 NS_ASSUME_NONNULL_BEGIN
+#endif
 
 /*!
  * @category NSDictionary (OFObject) \
  *	     NSDictionary+OFObject.h ObjFW-Bridge/NSDictionary+OFObject.h
  *
@@ -27,6 +29,8 @@
  * @brief Support for bridging NSDictionaries to OFDictionaries.
  */
 @interface NSDictionary (OFObject) <NSBridging>
 @end
 
+#ifdef NS_ASSUME_NONNULL_END
 NS_ASSUME_NONNULL_END
+#endif