diff --git a/src/lib/update/deliver.c b/src/lib/update/deliver.c
index 555e0f87..c6992b7f 100644
--- a/src/lib/update/deliver.c
+++ b/src/lib/update/deliver.c
@@ -55,7 +55,7 @@ deliver(struct sctstr *from, struct ichrstr *ip, int dir,
     int amt_moved;
     int amt_dst;
     int mobility;
-    float mcost;
+    double mcost;
     struct dchrstr *dp;
     int n;