d261f558e0a577ee269fe55215505668cdcb6f2a
markd
  Wed Jul 7 07:09:11 2021 -0700
Address several cases of possible uninitialized variables detected by -O3.  None of these appear to be actually bugs due to the flow of the code

diff --git src/lib/diGraph.c src/lib/diGraph.c
index a76204e..bce9e91 100644
--- src/lib/diGraph.c
+++ src/lib/diGraph.c
@@ -676,31 +676,31 @@
 	    slAddHead(&erList, er);
 	    }
 	}
     }
 freeHash(&hash);
 return erList;
 }
 
 void dgSwapEdges(struct diGraph *dg, struct dgEdgeRef *erList)
 /* Swap polarity of all edges in erList.  (Assumes you don't have
  * edges going both directions in graph.) */
 {
 struct dgEdgeRef *er;
 struct dgEdge *edge;
 struct dgNode *a, *b;
-struct dgConnection *con1, *con2;
+struct dgConnection *con1 = NULL, *con2 = NULL;
 
 /* Remove edges from next and previous list of all
  * involved nodes and swap nodes in edge itself. */
 for (er = erList; er != NULL; er = er->next)
     {
     edge = er->edge;
     a = edge->a;
     b = edge->b;
     dgRemoveFromConList(&a->nextList, b, &con1);
     dgRemoveFromConList(&b->prevList, a, &con2);
     edge->a = b;
     edge->b = a;
     con1->node = a;
     slAddHead(&b->nextList, con1);
     con2->node = b;