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diff --git a/sc4pd/headers/lang/PowerOfTwoAllocPool.h b/sc4pd/headers/lang/PowerOfTwoAllocPool.h
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+++ b/sc4pd/headers/lang/PowerOfTwoAllocPool.h
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+/*
+	SuperCollider real time audio synthesis system
+    Copyright (c) 2002 James McCartney. All rights reserved.
+	http://www.audiosynth.com
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+
+// Implements a power of two size class allocator.
+// There is no consolidation of free space. Once a chunk is allocated it
+// remains at that size from then on whether free or allocated.
+// It uses AdvancingAllocPool as its parent allocator.
+// It is very fast. This is used to allocate Unit output buffers.
+
+#ifndef _PowerOfTwoAllocPool_
+#define _PowerOfTwoAllocPool_
+
+#include <stdexcept>
+#include <stdlib.h>
+#include "clz.h"
+#include "AdvancingAllocPool.h"
+#include "SC_AllocPool.h"
+void post(const char *fmt, ...);
+void postbuf(const char *fmt, ...);
+
+template<class Hdr, class Obj, class Elem, int LargeObjSizeClass, int Align>
+class PowerOfTwoAllocPool 
+{
+public:
+	PowerOfTwoAllocPool(::AllocPool *inPool, 
+		size_t initSize = 64*1024, 
+		size_t growSize = 64*1024
+	)
+		{
+			mLargeObjPool = inPool;
+			mNumLargeObjects = 0;
+			mNumAlloc = 0;
+			mNumFree = 0;
+			size_t tooBigSize = (sizeof(Hdr) + (sizeof(Elem) << (LargeObjSizeClass-1))) + 1;
+			mSmallObjPool.Init(inPool, initSize, growSize, tooBigSize);
+			Init();
+			assert(SanityCheck());
+		}
+	~PowerOfTwoAllocPool()
+		{
+			assert(SanityCheck());
+			assert(mNumLargeObjects == 0); // you have to free the big ones yourself
+			mSmallObjPool.FreeAll();
+		}
+		
+	Obj* Alloc(int32 inNumElems)
+		{
+			//mNumAlloc++;
+			assert(SanityCheck());
+			int sizeclass = LOG2CEIL(inNumElems);
+			if (sizeclass >= LargeObjSizeClass) {
+				mNumLargeObjects++;
+				size_t size = sizeof(Hdr) + (sizeof(Elem) * inNumElems);
+				return (Obj*)mLargeObjPool->Alloc(size);
+			}
+			
+			// get from free list
+			Obj* obj = mFreeLists[sizeclass];
+			if (obj != NULL) {
+				// set free list to next element.
+				mFreeLists[sizeclass] = *(Obj**)obj;
+			} else {
+				// have to allocate it
+				size_t size = mSizes[sizeclass];
+				obj = (Obj*)mSmallObjPool.Alloc(size);
+				if (!obj) throw runtime_error("PowerOfTwoAllocPool out of memory");
+			}
+			//obj->mMagic = 'magk';
+			assert(SanityCheck());
+			return obj;
+		}
+	void Free(Obj* inObjPtr)
+		{
+			//mNumFree++;
+			assert(SanityCheck());
+			if (inObjPtr == 0) return;                   /* free(0) has no effect */
+			/*if (inObjPtr->mMagic != 'magk') {
+				postbuf("bad object\n");
+				throw runtime_error("bad object");
+			}*/
+			int sizeclass = inObjPtr->SizeClass();
+			if (sizeclass >= LargeObjSizeClass) {
+				mLargeObjPool->Free(inObjPtr);
+				mNumLargeObjects--;
+			} else {
+				Obj* nextfree = mFreeLists[sizeclass];
+				mFreeLists[sizeclass] = inObjPtr;
+				*(Obj**)inObjPtr = nextfree;
+			}
+			assert(SanityCheck());
+		}
+	void FreeAll()
+		{
+			assert(mNumLargeObjects == 0); // you have to free the big ones yourself
+			mSmallObjPool.FreeAll();
+			Init();
+		}
+	
+	bool SanityCheck()
+		{
+			//postbuf("PowerOfTwoAllocPool::SanityCheck %d %d\n", mNumAlloc, mNumFree);
+			mLargeObjPool->DoCheckPool();
+			mSmallObjPool.SanityCheck();
+			for (int i=0; i<LargeObjSizeClass; ++i) {
+				Obj* obj = mFreeLists[i];
+				for (int j=0; obj; ++j) {
+					if (j>=1000) {
+						post("linked loop??\n");
+						throw runtime_error("linked loop??\n");
+						return false;
+					}
+					obj = *(Obj**)obj;
+				}
+			}
+			return true;
+		}
+private:
+	void Init()
+		{
+			for (int i=0; i<LargeObjSizeClass; ++i) {
+				mFreeLists[i] = NULL;
+				size_t size = sizeof(Hdr) + (sizeof(Elem) << i);
+				mSizes[i] = (size + (Align-1)) & ~(Align-1); // alignment
+			}
+		}
+	
+	Obj* mFreeLists[LargeObjSizeClass];
+	size_t mSizes[LargeObjSizeClass];
+	AllocPool* mLargeObjPool;
+	AdvancingAllocPool mSmallObjPool;
+	int mNumLargeObjects;
+	int mNumAlloc, mNumFree;
+};
+
+
+#endif
+