no pointer arithmetic on void pointers.  noted by IRIX cc

--HG--
branch : HEAD
diff --git a/lib/zip_source_buffer.c b/lib/zip_source_buffer.c
index 5ea7ff5..d150786 100644
--- a/lib/zip_source_buffer.c
+++ b/lib/zip_source_buffer.c
@@ -1,5 +1,5 @@
 /*
-  $NiH: zip_source_buffer.c,v 1.1 2004/11/18 17:26:51 wiz Exp $
+  $NiH: zip_source_buffer.c,v 1.2 2004/12/22 16:31:59 dillo Exp $
 
   zip_source_buffer.c -- create zip data source from buffer
   Copyright (C) 1999, 2003, 2004 Dieter Baron and Thomas Klausner
@@ -72,7 +72,7 @@
     }
 
     f->data = data;
-    f->end = data+len;
+    f->end = ((const char *)data)+len;
     f->freep = freep;
     f->mtime = time(NULL);