diff -u -r --new-file libc/sysdeps/s390/bits/string.h libc-s390/sysdeps/s390/bits/string.h
--- libc/sysdeps/s390/bits/string.h	Tue Nov 21 18:30:12 2000
+++ libc-s390/sysdeps/s390/bits/string.h	Tue Nov 21 18:21:19 2000
@@ -131,6 +131,8 @@
 			  "   jz   2f\n"
 			  "   la   %1,1(%1)\n"
 			  "   brct %2,1b\n"
+			  "   la   %0,0(%0,%1)\n"
+			  "   xc   0(1,%0),0(%0\n)
 			  "2:"
                           : "+&a" (__dest), "+&a" (__src), "+&d" (__n) :
                           : "cc", "memory", "0" );