diff --git a/Tools/bgen/bgen/bgenBuffer.py b/Tools/bgen/bgen/bgenBuffer.py
index f895315..bc11e64 100644
--- a/Tools/bgen/bgen/bgenBuffer.py
+++ b/Tools/bgen/bgen/bgenBuffer.py
@@ -38,10 +38,11 @@
         self.sizeformat = sizeformat or type2format[sizetype]
         self.label_needed = 0
 
-    def getDeclarations(self, name, reference=False):
+    def getArgDeclarations(self, name, reference=False):
         if reference:
             raise RuntimeError, "Cannot pass buffer types by reference"
-        return self.getBufferDeclarations(name) + self.getSizeDeclarations(name)
+        return (self.getBufferDeclarations(name) + 
+                self.getSizeDeclarations(name))
 
     def getBufferDeclarations(self, name):
         return self.getInputBufferDeclarations(name) + self.getOutputBufferDeclarations(name)
@@ -53,10 +54,10 @@
         return ["%s %s__out__[%s]" % (self.datatype, name, self.size)]
 
     def getSizeDeclarations(self, name):
-        return [
-            "%s %s__len__" %(self.sizetype, name),
-            "int %s__in_len__" %(name)
-            ]
+        return ["%s %s__len__" %(self.sizetype, name)]
+
+    def getAuxDeclarations(self, name):
+        return ["int %s__in_len__" %(name)]
 
     def getargsFormat(self):
         return "s#"
@@ -189,6 +190,9 @@
         return ["%s *%s__in__" % (self.type, name)]
 
     def getSizeDeclarations(self, name):
+        return []
+        
+    def getAuxDeclarations(self, name):
         return ["int %s__in_len__" % (name)]
 
     def getOutputBufferDeclarations(self, name):
@@ -248,6 +252,9 @@
     def getSizeDeclarations(self, name):
         return []
 
+    def getAuxDeclarations(self, name):
+        return []
+
     def passOutput(self, name):
         return "&%s__out__" % name
 
@@ -262,5 +269,8 @@
     def getSizeDeclarations(self, name):
         return []
 
+    def getAuxDeclarations(self, name):
+        return []
+
     def passOutput(self, name):
         return "%s__out__" % name
diff --git a/Tools/bgen/bgen/bgenStackBuffer.py b/Tools/bgen/bgen/bgenStackBuffer.py
index 32f97f9..431bb73 100644
--- a/Tools/bgen/bgen/bgenStackBuffer.py
+++ b/Tools/bgen/bgen/bgenStackBuffer.py
@@ -23,6 +23,9 @@
     """
 
     def getSizeDeclarations(self, name):
+        return []
+
+    def getAuxDeclarations(self, name):
         return ["int %s__len__ = %s" % (name, self.size)]
 
     def passOutput(self, name):
diff --git a/Tools/bgen/bgen/bgenStringBuffer.py b/Tools/bgen/bgen/bgenStringBuffer.py
index 01155b3..a232f83 100644
--- a/Tools/bgen/bgen/bgenStringBuffer.py
+++ b/Tools/bgen/bgen/bgenStringBuffer.py
@@ -26,6 +26,9 @@
     def getSizeDeclarations(self, name):
         return []
 
+    def getAuxDeclarations(self, name):
+        return []
+
     def getargsFormat(self):
         return "s"
 
diff --git a/Tools/bgen/bgen/bgenType.py b/Tools/bgen/bgen/bgenType.py
index a31aa74..f7cb388 100644
--- a/Tools/bgen/bgen/bgenType.py
+++ b/Tools/bgen/bgen/bgenType.py
@@ -24,17 +24,25 @@
 
         Example: int.declare('spam') prints "int spam;"
         """
-        for decl in self.getDeclarations(name, reference):
+        for decl in self.getArgDeclarations(name, reference):
+            Output("%s;", decl)
+        for decl in self.getAuxDeclarations(name):
             Output("%s;", decl)
 
-    def getDeclarations(self, name, reference=False):
-        """Return a string declaring a variable or argument, without
-        any syntactic adornment"""
+    def getArgDeclarations(self, name, reference=False):
+        """Return the main part of the declarations for this type: the items
+        that will be passed as arguments in the C/C++ function call."""
         if reference:
             return ["%s& %s" % (self.typeName, name)]
         else:
             return ["%s %s" % (self.typeName, name)]
 
+    def getAuxDeclarations(self, name):
+        """Return any auxiliary declarations needed for implementing this
+        type, such as helper variables used to hold sizes, etc. These declarations
+        are not part of the C/C++ function call interface."""
+        return []
+        
     def getargs(self):
         return self.getargsFormat(), self.getargsArgs()
 
@@ -187,7 +195,10 @@
         self.substitute = substitute
         self.typeName = None    # Don't show this argument in __doc__ string
 
-    def getDeclarations(self, name, reference=False):
+    def getArgDeclarations(self, name, reference=False):
+        return []
+
+    def getAuxDeclarations(self, name, reference=False):
         return []
 
     def getargsFormat(self):
diff --git a/Tools/bgen/bgen/bgenVariable.py b/Tools/bgen/bgen/bgenVariable.py
index bc1199c..6edeb87 100644
--- a/Tools/bgen/bgen/bgenVariable.py
+++ b/Tools/bgen/bgen/bgenVariable.py
@@ -45,11 +45,12 @@
         elif self.flags != SelfMode:
             self.type.declare(self.name)
 
-    def getDeclarations(self):
-        """Return the unadorned declaration of the variable,
-        suitable for use in a formal parameter list."""
+    def getArgDeclarations(self):
         refmode = (self.flags & RefMode)
-        return self.type.getDeclarations(self.name, reference=refmode)
+        return self.type.getArgDeclarations(self.name, reference=refmode)
+    
+    def getAuxDeclarations(self):
+        return self.type.getAuxDeclarations(self.name)
 
     def getargsFormat(self):
         """Call the type's getargsFormatmethod."""
diff --git a/Tools/bgen/bgen/scantools.py b/Tools/bgen/bgen/scantools.py
index 67539e0..1ebf70d 100644
--- a/Tools/bgen/bgen/scantools.py
+++ b/Tools/bgen/bgen/scantools.py
@@ -482,8 +482,7 @@
         modifiers = self.getmodifiers(match)
         type = self.pythonizename(type)
         name = self.pythonizename(name)
-        if name in self.alreadydone:
-            self.report("Name has already been defined: %r", name)
+        if self.checkduplicate(name):
             return
         self.report("==> %s %s <==", type, name)
         if self.blacklisted(type, name):
@@ -499,7 +498,6 @@
             ##  self.report("    %r", arg)
             self.report("*** %s %s unmanageable", type, name)
             return
-        self.alreadydone.append(name)
         if modifiers:
             self.generate(type, name, arglist, modifiers)
         else:
@@ -508,6 +506,13 @@
     def getmodifiers(self, match):
         return []
 
+    def checkduplicate(self, name):
+        if name in self.alreadydone:
+            self.report("Name has already been defined: %r", name)
+            return True
+        self.alreadydone.append(name)
+        return False
+
     def pythonizename(self, name):
         name = re.sub("\*", " ptr", name)
         name = name.strip()