diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index 0bef623..a217402 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -6460,7 +6460,7 @@
     /*
      * Find all *.txt files.
      */
-    dirlen = STRLEN(dir);
+    dirlen = (int)STRLEN(dir);
     STRCPY(NameBuff, dir);
     STRCAT(NameBuff, "/**/*");
     STRCAT(NameBuff, ext);