diff -Nru /n/sources/plan9/sys/src/libregexp/regcomp.c /sys/src/libregexp/regcomp.c
--- /n/sources/plan9/sys/src/libregexp/regcomp.c	Fri Jul 23 21:16:07 2010
+++ /sys/src/libregexp/regcomp.c	Sun Aug  9 00:00:00 2015
@@ -113,7 +113,7 @@
 	while(*s)
 		*cp++ = *s++;
 	*cp++ = c;
-	*cp = '\0'; 
+	*cp = '\0';
 	rcerror(buf);
 }
 
@@ -121,7 +121,7 @@
 cant(char *s)
 {
 	char buf[100];
-	strcpy(buf, "can't happen: ");
+	strncpy(buf, "can't happen: ", sizeof(buf));
 	strcat(buf, s);
 	rcerror(buf);
 }
diff -Nru /n/sources/plan9/sys/src/libregexp/regerror.c /sys/src/libregexp/regerror.c
--- /n/sources/plan9/sys/src/libregexp/regerror.c	Sun Dec 12 01:22:31 1999
+++ /sys/src/libregexp/regerror.c	Sun Aug  9 00:00:00 2015
@@ -7,7 +7,7 @@
 {
 	char buf[132];
 
-	strcpy(buf, "regerror: ");
+	strncpy(buf, "regerror: ", sizeof(buf));
 	strcat(buf, s);
 	strcat(buf, "\n");
 	write(2, buf, strlen(buf));
diff -Nru /n/sources/plan9/sys/src/libregexp/regexec.c /sys/src/libregexp/regexec.c
--- /n/sources/plan9/sys/src/libregexp/regexec.c	Sat Jan 12 20:47:52 2008
+++ /sys/src/libregexp/regexec.c	Sun Aug  9 00:00:00 2015
@@ -172,7 +172,7 @@
 		return -1;
 	relist1 = malloc(BIGLISTSIZE*sizeof(Relist));
 	if(relist1 == nil){
-		free(relist1);
+		free(relist0);
 		return -1;
 	}
 	j->relist[0] = relist0;
diff -Nru /n/sources/plan9/sys/src/libregexp/rregsub.c /sys/src/libregexp/rregsub.c
--- /n/sources/plan9/sys/src/libregexp/rregsub.c	Wed Apr 25 19:01:33 2001
+++ /sys/src/libregexp/rregsub.c	Sun Aug  9 00:00:00 2015
@@ -28,7 +28,7 @@
 			case '8':
 			case '9':
 				i = *sp-'0';
-				if(mp[i].rsp != 0 && mp!=0 && ms>i)
+				if(mp!=0 && mp[i].rsp != 0 && ms>i)
 					for(ssp = mp[i].rsp;
 					     ssp < mp[i].rep;
 					     ssp++)
@@ -47,9 +47,8 @@
 					*dp++ = *sp;
 				break;
 			}
-		}else if(*sp == '&'){				
+		}else if(*sp == '&'){
 			if(mp[0].rsp != 0 && mp!=0 && ms>0)
-			if(mp[0].rsp != 0)
 				for(ssp = mp[0].rsp;
 				     ssp < mp[0].rep; ssp++)
 					if(dp < ep)