From fca21c8fc0bd4da8636aad94bf052ff47bab3c58 Mon Sep 17 00:00:00 2001
From: Tim Edwards <tim@opencircuitdesign.com>
Date: Mon, 5 Apr 2021 14:16:28 -0400
Subject: [PATCH] Corrected an error causing weird and undefined behavior when
 extracting substrate regions, due to failure to clean up the tagged tiles
 after exiting a search due to finding a substrate type that was not the
 global substrate.

---
 extract/ExtBasic.c | 22 ++--------------------
 extract/ExtHier.c  |  7 ++++++-
 2 files changed, 8 insertions(+), 21 deletions(-)

diff --git a/extract/ExtBasic.c b/extract/ExtBasic.c
index c5e0b1c3..90d33753 100644
--- a/extract/ExtBasic.c
+++ b/extract/ExtBasic.c
@@ -1821,26 +1821,8 @@ extOutputDevices(def, transList, outFile)
 		    extTransFindSubs(reg->treg_tile, t, tmask, def, &node, NULL);
 
 		    if ((node == NULL) && (TTMaskHasType(tmask, TT_SPACE))) {
-			/* Device node is possibly the substrate.  But:  Note	*/
-			/* that TT_SPACE in the mask covers all planes, and it	*/
-			/* is not possible to specify TT_SPACE in a single	*/
-			/* plane.  So it is necessary to check for any		*/
-			/* shielding types that	block the substrate.		*/
-
-			if (!TTMaskIsZero(&ExtCurStyle->exts_globSubstrateShieldTypes))
-			{
-			    extTransFindSubs(reg->treg_tile, t, 
-					&ExtCurStyle->exts_globSubstrateShieldTypes,
-					def, &node, NULL);
-			}
-			if ((glob_subsnode == NULL) || (node != NULL)) {
-			    /* See if there is another matching device record	*/
-			    /* with a different terminal type, and try again.	*/
-			    devptr = extDevFindMatch(devptr, t);
-			    break;
-			}
-			else if ((node == NULL) && (glob_subsnode != NULL))
-			    node = glob_subsnode;
+			/* Device node is the global substrate. */
+			node = glob_subsnode;
 		    }
 		    else if (node == NULL) {
 			/* See if there is another matching device record	*/
diff --git a/extract/ExtHier.c b/extract/ExtHier.c
index 1426abec..8e51d155 100644
--- a/extract/ExtHier.c
+++ b/extract/ExtHier.c
@@ -127,7 +127,11 @@ extHierSubstrate(ha, use, x, y)
 
     /* Find the child's substrate node */
     nodeList = extFindNodes(use->cu_def, (Rect *) NULL, TRUE);
-    if (nodeList == NULL) return;
+    if (nodeList == NULL)
+    {
+    	ExtResetTiles(use->cu_def, extUnInit);
+	return;
+    }
 
     /* Check if the child's substrate node is covered by any substrate	*/
     /* shield type (e.g., deep nwell).  This is a stupid-simple check	*/
@@ -161,6 +165,7 @@ extHierSubstrate(ha, use, x, y)
 			extHierSubShieldFunc, (ClientData)NULL) != 0)
     	    {
     		freeMagic(nodeList);
+    		ExtResetTiles(use->cu_def, extUnInit);
 		return;
 	    }
 	}