diff --git a/Headers/gnustep/base/NSObject.h b/Headers/gnustep/base/NSObject.h
index e62f720f1..3e732e5c6 100644
--- a/Headers/gnustep/base/NSObject.h
+++ b/Headers/gnustep/base/NSObject.h
@@ -140,6 +140,7 @@ enum {NSNotFound = 0x7fffffff};
 - shouldNotImplement:(SEL)aSel;
 + (Class) autoreleaseClass;
 + (void) setAutoreleaseClass: (Class)aClass;
++ (void) enableDoubleReleaseCheck: (BOOL)enable;
 - read: (TypedStream*)aStream;
 - write: (TypedStream*)aStream;
 @end