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diff --git a/mesalib/src/glu/sgi/libtess/priorityq-heap.c b/mesalib/src/glu/sgi/libtess/priorityq-heap.c
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index 000000000..e3a6c6068
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+++ b/mesalib/src/glu/sgi/libtess/priorityq-heap.c
@@ -0,0 +1,252 @@
+/*
+ * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
+ * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice including the dates of first publication and
+ * either this permission notice or a reference to
+ * http://oss.sgi.com/projects/FreeB/
+ * shall be included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
+ * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Silicon Graphics, Inc.
+ * shall not be used in advertising or otherwise to promote the sale, use or
+ * other dealings in this Software without prior written authorization from
+ * Silicon Graphics, Inc.
+ */
+/*
+** Author: Eric Veach, July 1994.
+**
+*/
+
+#include <stddef.h>
+#include <assert.h>
+#include "priorityq-heap.h"
+#include "memalloc.h"
+
+#define INIT_SIZE 32
+
+#define TRUE 1
+#define FALSE 0
+
+#ifdef FOR_TRITE_TEST_PROGRAM
+#define LEQ(x,y) (*pq->leq)(x,y)
+#else
+/* Violates modularity, but a little faster */
+#include "geom.h"
+#define LEQ(x,y) VertLeq((GLUvertex *)x, (GLUvertex *)y)
+#endif
+
+/* really __gl_pqHeapNewPriorityQ */
+PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) )
+{
+ PriorityQ *pq = (PriorityQ *)memAlloc( sizeof( PriorityQ ));
+ if (pq == NULL) return NULL;
+
+ pq->size = 0;
+ pq->max = INIT_SIZE;
+ pq->nodes = (PQnode *)memAlloc( (INIT_SIZE + 1) * sizeof(pq->nodes[0]) );
+ if (pq->nodes == NULL) {
+ memFree(pq);
+ return NULL;
+ }
+
+ pq->handles = (PQhandleElem *)memAlloc( (INIT_SIZE + 1) * sizeof(pq->handles[0]) );
+ if (pq->handles == NULL) {
+ memFree(pq->nodes);
+ memFree(pq);
+ return NULL;
+ }
+
+ pq->initialized = FALSE;
+ pq->freeList = 0;
+ pq->leq = leq;
+
+ pq->nodes[1].handle = 1; /* so that Minimum() returns NULL */
+ pq->handles[1].key = NULL;
+ return pq;
+}
+
+/* really __gl_pqHeapDeletePriorityQ */
+void pqDeletePriorityQ( PriorityQ *pq )
+{
+ memFree( pq->handles );
+ memFree( pq->nodes );
+ memFree( pq );
+}
+
+
+static void FloatDown( PriorityQ *pq, long curr )
+{
+ PQnode *n = pq->nodes;
+ PQhandleElem *h = pq->handles;
+ PQhandle hCurr, hChild;
+ long child;
+
+ hCurr = n[curr].handle;
+ for( ;; ) {
+ child = curr << 1;
+ if( child < pq->size && LEQ( h[n[child+1].handle].key,
+ h[n[child].handle].key )) {
+ ++child;
+ }
+
+ assert(child <= pq->max);
+
+ hChild = n[child].handle;
+ if( child > pq->size || LEQ( h[hCurr].key, h[hChild].key )) {
+ n[curr].handle = hCurr;
+ h[hCurr].node = curr;
+ break;
+ }
+ n[curr].handle = hChild;
+ h[hChild].node = curr;
+ curr = child;
+ }
+}
+
+
+static void FloatUp( PriorityQ *pq, long curr )
+{
+ PQnode *n = pq->nodes;
+ PQhandleElem *h = pq->handles;
+ PQhandle hCurr, hParent;
+ long parent;
+
+ hCurr = n[curr].handle;
+ for( ;; ) {
+ parent = curr >> 1;
+ hParent = n[parent].handle;
+ if( parent == 0 || LEQ( h[hParent].key, h[hCurr].key )) {
+ n[curr].handle = hCurr;
+ h[hCurr].node = curr;
+ break;
+ }
+ n[curr].handle = hParent;
+ h[hParent].node = curr;
+ curr = parent;
+ }
+}
+
+/* really __gl_pqHeapInit */
+void pqInit( PriorityQ *pq )
+{
+ long i;
+
+ /* This method of building a heap is O(n), rather than O(n lg n). */
+
+ for( i = pq->size; i >= 1; --i ) {
+ FloatDown( pq, i );
+ }
+ pq->initialized = TRUE;
+}
+
+/* really __gl_pqHeapInsert */
+/* returns LONG_MAX iff out of memory */
+PQhandle pqInsert( PriorityQ *pq, PQkey keyNew )
+{
+ long curr;
+ PQhandle free;
+
+ curr = ++ pq->size;
+ if( (curr*2) > pq->max ) {
+ PQnode *saveNodes= pq->nodes;
+ PQhandleElem *saveHandles= pq->handles;
+
+ /* If the heap overflows, double its size. */
+ pq->max <<= 1;
+ pq->nodes = (PQnode *)memRealloc( pq->nodes,
+ (size_t)
+ ((pq->max + 1) * sizeof( pq->nodes[0] )));
+ if (pq->nodes == NULL) {
+ pq->nodes = saveNodes; /* restore ptr to free upon return */
+ return LONG_MAX;
+ }
+ pq->handles = (PQhandleElem *)memRealloc( pq->handles,
+ (size_t)
+ ((pq->max + 1) *
+ sizeof( pq->handles[0] )));
+ if (pq->handles == NULL) {
+ pq->handles = saveHandles; /* restore ptr to free upon return */
+ return LONG_MAX;
+ }
+ }
+
+ if( pq->freeList == 0 ) {
+ free = curr;
+ } else {
+ free = pq->freeList;
+ pq->freeList = pq->handles[free].node;
+ }
+
+ pq->nodes[curr].handle = free;
+ pq->handles[free].node = curr;
+ pq->handles[free].key = keyNew;
+
+ if( pq->initialized ) {
+ FloatUp( pq, curr );
+ }
+ assert(free != LONG_MAX);
+ return free;
+}
+
+/* really __gl_pqHeapExtractMin */
+PQkey pqExtractMin( PriorityQ *pq )
+{
+ PQnode *n = pq->nodes;
+ PQhandleElem *h = pq->handles;
+ PQhandle hMin = n[1].handle;
+ PQkey min = h[hMin].key;
+
+ if( pq->size > 0 ) {
+ n[1].handle = n[pq->size].handle;
+ h[n[1].handle].node = 1;
+
+ h[hMin].key = NULL;
+ h[hMin].node = pq->freeList;
+ pq->freeList = hMin;
+
+ if( -- pq->size > 0 ) {
+ FloatDown( pq, 1 );
+ }
+ }
+ return min;
+}
+
+/* really __gl_pqHeapDelete */
+void pqDelete( PriorityQ *pq, PQhandle hCurr )
+{
+ PQnode *n = pq->nodes;
+ PQhandleElem *h = pq->handles;
+ long curr;
+
+ assert( hCurr >= 1 && hCurr <= pq->max && h[hCurr].key != NULL );
+
+ curr = h[hCurr].node;
+ n[curr].handle = n[pq->size].handle;
+ h[n[curr].handle].node = curr;
+
+ if( curr <= -- pq->size ) {
+ if( curr <= 1 || LEQ( h[n[curr>>1].handle].key, h[n[curr].handle].key )) {
+ FloatDown( pq, curr );
+ } else {
+ FloatUp( pq, curr );
+ }
+ }
+ h[hCurr].key = NULL;
+ h[hCurr].node = pq->freeList;
+ pq->freeList = hCurr;
+}