diff --git a/src/join.c b/src/join.c
index 7b24dc20e..5fd02c60f 100644
--- a/src/join.c
+++ b/src/join.c
@@ -1,5 +1,5 @@
 /* join - join lines of two files on a common field
-   Copyright (C) 91, 1995-1999 Free Software Foundation, Inc.
+   Copyright (C) 91, 1995-2000 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -708,11 +708,12 @@ void
 make_blank (struct line *blank, int count)
 {
   int i;
-  char *buffer;
+  unsigned char *buffer;
   struct field *fields;
   blank->nfields = count;
   blank->buf.size = blank->buf.length = count + 1;
-  blank->buf.buffer = buffer = xmalloc (blank->buf.size);
+  blank->buf.buffer = xmalloc (blank->buf.size);
+  buffer = (unsigned char *) blank->buf.buffer;
   blank->fields = fields =
     (struct field *) xmalloc (sizeof (struct field) * count);
   for (i = 0; i < count; i++)