7112954574ae6a8429a230d895733513f28a22c9
hiram
  Wed Oct 6 14:08:59 2010 -0700
there are no calls to hTrackDb(NULL) except in obsolete hgText.c
diff --git src/hg/lib/hdb.c src/hg/lib/hdb.c
index ee75743..587e258 100644
--- src/hg/lib/hdb.c
+++ src/hg/lib/hdb.c
@@ -3565,7 +3565,7 @@
 {
 static char *existingDb = NULL;
 static struct trackDb *tdbList = NULL;
-if ((NULL == db) || differentStringNullOk(existingDb, db))
+if (differentStringNullOk(existingDb, db))
     {
     tdbList = loadTrackDb(db, NULL);
     tdbList = trackDbLinkUpGenerations(tdbList);