squash a -Wsign-compare and a -Wconversion compiler warnings

diff --git a/lib/twopigen/circle.c b/lib/twopigen/circle.c
index 375fd5c2de8b2a944f548cf0419c28d0a8048561..e9b819d1bab35b7bfb52b60a38f4df840c316aa7 100644 (file)
--- a/lib/twopigen/circle.c
+++ b/lib/twopigen/circle.c
@@ -90,7 +90,7 @@ static Agnode_t *findCenterNode(Agraph_t * g)
 {
     Agnode_t *n;
     Agnode_t *center = NULL;
-    int maxNStepsToLeaf = 0;
+    uint64_t maxNStepsToLeaf = 0;
 
     /* With just 1 or 2 nodes, return anything. */
     if (agnnodes(g) <= 2)