diff -urNp ncompress-4.2.4-orig/compress42.c ncompress-4.2.4/compress42.c
--- ncompress-4.2.4-orig/compress42.c	2012-01-03 15:13:58.014222927 +0100
+++ ncompress-4.2.4/compress42.c	2012-01-03 15:15:17.117097419 +0100
@@ -1441,7 +1441,7 @@ compress(fdin, fdout)
 					boff = -(((OBUFSIZ<<3)-boff)%(n_bits<<3));
 					bytes_out += OBUFSIZ;
 
-					memcpy(outbuf, outbuf+OBUFSIZ, (outbits>>3)+1);
+					memmove(outbuf, outbuf+OBUFSIZ, (outbits>>3)+1);
 					memset(outbuf+(outbits>>3)+1, '\0', OBUFSIZ);
 				}