updated for version 7.4.072
Problem:    Crash when using Insert mode completion.
Solution:   Avoid going past the end of pum_array. (idea by Fransisco Lopes)
diff --git a/src/popupmnu.c b/src/popupmnu.c
index 44ed878..8ff0711 100644
--- a/src/popupmnu.c
+++ b/src/popupmnu.c
@@ -282,6 +282,10 @@
     int		round;
     int		n;
 
+    /* Never display more than we have */
+    if (pum_first > pum_size - pum_height)
+	pum_first = pum_size - pum_height;
+
     if (pum_scrollbar)
     {
 	thumb_heigth = pum_height * pum_height / pum_size;
@@ -672,10 +676,6 @@
 #endif
     }
 
-    /* Never display more than we have */
-    if (pum_first > pum_size - pum_height)
-	pum_first = pum_size - pum_height;
-
     if (!resized)
 	pum_redraw();