patch 7.4.1580
Problem:    Crash when using function reference. (Luchr)
Solution:   Set initial refcount. (Ken Takata, closes #690)
diff --git a/src/eval.c b/src/eval.c
index 5069324..85f2092 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -21705,6 +21705,7 @@
 	/* Turn "dict.Func" into a partial for "Func" with "dict". */
 	if (pt != NULL)
 	{
+	    pt->pt_refcount = 1;
 	    pt->pt_dict = selfdict;
 	    selfdict = NULL;
 	    pt->pt_name = rettv->vval.v_string;