Index: generic/nsf.c
===================================================================
diff -u -N -ra25c4bed9bbde4420c60d971812ed29510ed941b -r1aa07d20cab9258b273f984cd694673dfa6a86b8
--- generic/nsf.c	(.../nsf.c)	(revision a25c4bed9bbde4420c60d971812ed29510ed941b)
+++ generic/nsf.c	(.../nsf.c)	(revision 1aa07d20cab9258b273f984cd694673dfa6a86b8)
@@ -14232,7 +14232,7 @@
 
   if (likely(cmd == NULL)) {
     NsfMethodContext *mcPtr = methodObj->internalRep.twoPtrValue.ptr1;
-    int               nsfObjectMethodEpoch = rst->objectMethodEpoch;
+    unsigned int               nsfObjectMethodEpoch = rst->objectMethodEpoch;
 
     if (methodObj->typePtr == &NsfObjectMethodObjType
         && mcPtr->context == object
@@ -14290,7 +14290,7 @@
       /* check for an instance method */
       NsfClass         *currentClass = object->cl;
       NsfMethodContext *mcPtr0 = methodObj->internalRep.twoPtrValue.ptr1;
-      int               nsfInstanceMethodEpoch = rst->instanceMethodEpoch;
+      unsigned int               nsfInstanceMethodEpoch = rst->instanceMethodEpoch;
 
 #if defined(METHOD_OBJECT_TRACE)
       fprintf(stderr, "... method %p/%d '%s' type? %d context? %d nsfMethodEpoch %d => %d\n",
@@ -25103,7 +25103,7 @@
       || objPtr->typePtr == &NsfInstanceMethodObjType
       ) {
     NsfMethodContext *mcPtr = objPtr->internalRep.twoPtrValue.ptr1;
-    int currentMethodEpoch = objPtr->typePtr == &NsfObjectMethodObjType ?
+    unsigned int currentMethodEpoch = objPtr->typePtr == &NsfObjectMethodObjType ?
       RUNTIME_STATE(interp)->objectMethodEpoch :
       RUNTIME_STATE(interp)->instanceMethodEpoch;
     Tcl_Command cmd = mcPtr->cmd;
Index: generic/nsfInt.h
===================================================================
diff -u -N -r81788340d06828bb7131be38cc31858cf842612e -r1aa07d20cab9258b273f984cd694673dfa6a86b8
--- generic/nsfInt.h	(.../nsfInt.h)	(revision 81788340d06828bb7131be38cc31858cf842612e)
+++ generic/nsfInt.h	(.../nsfInt.h)	(revision 1aa07d20cab9258b273f984cd694673dfa6a86b8)
@@ -555,7 +555,7 @@
   const char *volatileVarName;
 #if defined(PER_OBJECT_PARAMETER_CACHING)
   NsfParsedParam *parsedParamPtr;
-  int classParamPtrEpoch;
+  unsigned int classParamPtrEpoch;
 #endif
   CheckOptions checkoptions;
 } NsfObjectOpt;
@@ -914,10 +914,10 @@
   Tcl_Command colonCmd;           /* cmdPtr of cmd ":" to dispatch via cmdResolver */
   Proc fakeProc;                  /* dummy proc structure, used for C-implemented methods with local scope */
   Tcl_Command currentMixinCmdPtr; /* cmdPtr of currently active mixin, used for "info activemixin" */
-  int objectMethodEpoch;
-  int instanceMethodEpoch;
+  unsigned int objectMethodEpoch;
+  unsigned int instanceMethodEpoch;
 #if defined(PER_OBJECT_PARAMETER_CACHING)
-  int classParamPtrEpoch;
+  unsigned int classParamPtrEpoch;
 #endif
   unsigned int overloadedMethods; /* bit-array for tracking overloaded methods */
   Tcl_Obj **methodObjNames;       /* global objects of nsf */
@@ -1191,7 +1191,7 @@
 			   Tcl_Obj     *objPtr,
 			   Tcl_ObjType *objectType,
 			   void        *context,
-			   int          methodEpoch,
+			   unsigned int methodEpoch,
 			   Tcl_Command  cmd,
 			   NsfClass    *cl,
 			   unsigned int flags)
@@ -1204,7 +1204,7 @@
   void        *context;
   Tcl_Command  cmd;
   NsfClass    *cl;
-  int          methodEpoch;
+  unsigned int methodEpoch;
   unsigned int flags;
 } NsfMethodContext;
 
Index: generic/nsfObj.c
===================================================================
diff -u -N -r16324e94fee054ff57d403e5b51cf96117317ea0 -r1aa07d20cab9258b273f984cd694673dfa6a86b8
--- generic/nsfObj.c	(.../nsfObj.c)	(revision 16324e94fee054ff57d403e5b51cf96117317ea0)
+++ generic/nsfObj.c	(.../nsfObj.c)	(revision 1aa07d20cab9258b273f984cd694673dfa6a86b8)
@@ -131,7 +131,7 @@
     register Tcl_Obj *objPtr,   	/* The object to convert. */
     Tcl_ObjType *objectType,
     void *context,			/* context (to avoid over-eager sharing) */
-    int methodEpoch,			/* methodEpoch */
+    unsigned int methodEpoch,		/* methodEpoch */
     Tcl_Command cmd,	  		/* the tclCommand behind the method */
     NsfClass *cl,	  		/* the object/class where the method was defined */
     unsigned int flags			/* flags */