diff --git a/src/syntax.c b/src/syntax.c
index 48e7152..0212052 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -4084,8 +4084,8 @@
 
     if (msg_col >= endcol)	// output at least one space
 	endcol = msg_col + 1;
-    if (Columns <= endcol)	// avoid hang for tiny window
-	endcol = Columns - 1;
+    if (Columns <= (long)endcol)	// avoid hang for tiny window
+	endcol = (int)(Columns - 1);
 
     msg_advance(endcol);
     if (SYN_CLSTR(curwin->w_s)[id].scl_list != NULL)