--- tc.prompt.c.orig	Sat Sep  5 01:17:01 1998
+++ tc.prompt.c	Fri Apr 16 05:15:55 1999
@@ -212,7 +212,7 @@
 		if (what == FMT_HISTORY)
 		    fmthist('R', info, str = cbuff, sizeof(cbuff));
 		if (str != NULL)
-		    for (; *str; *p++ = attributes | *str++)
+		    for (; *str; *p++ = attributes | ((unsigned char)*str++))
 			if (p >= ep) break;
 		break;
 	    case '#':
