Index: lib/libedit/chartype.c
===================================================================
--- lib/libedit/chartype.c
+++ lib/libedit/chartype.c
@@ -37,6 +37,7 @@
 __FBSDID("$FreeBSD$");
 
 #include <ctype.h>
+#include <limits.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -182,17 +183,11 @@
 protected size_t
 ct_enc_width(Char c)
 {
-	/* UTF-8 encoding specific values */
-	if (c < 0x80)
-		return 1;
-	else if (c < 0x0800)
-		return 2;
-	else if (c < 0x10000)
-		return 3;
-	else if (c < 0x110000)
-		return 4;
-	else
-		return 0; /* not a valid codepoint */
+	char buf[MB_LEN_MAX];
+	int size;
+	if ((size = wctomb(buf, c)) < 0)
+		return 0;
+	return (size_t)size;
 }
 
 protected ssize_t
Index: lib/libedit/editline.3
===================================================================
--- lib/libedit/editline.3
+++ lib/libedit/editline.3
@@ -28,7 +28,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd April 28, 2017
+.Dd November 9, 2018
 .Dt EDITLINE 3
 .Os
 .Sh NAME
@@ -183,8 +183,6 @@
 locale set by the application program and never uses
 .Xr setlocale 3
 to change the locale.
-The only locales supported are UTF-8 and the default C or POSIX locale.
-If any other locale is set, behaviour is undefined.
 .Sh LINE EDITING FUNCTIONS
 The line editing functions use a common data structure,
 .Fa EditLine ,
Index: lib/libedit/el.h
===================================================================
--- lib/libedit/el.h
+++ lib/libedit/el.h
@@ -56,7 +56,6 @@
 #define	NO_TTY		0x02
 #define	EDIT_DISABLED	0x04
 #define	UNBUFFERED	0x08
-#define	CHARSET_IS_UTF8 0x10
 #define	NARROW_HISTORY	0x40
 
 typedef unsigned char el_action_t;	/* Index to command array	*/
Index: lib/libedit/el.c
===================================================================
--- lib/libedit/el.c
+++ lib/libedit/el.c
@@ -99,10 +99,6 @@
          * Initialize all the modules. Order is important!!!
          */
 	el->el_flags = 0;
-	if (setlocale(LC_CTYPE, NULL) != NULL){
-		if (strcmp(nl_langinfo(CODESET), "UTF-8") == 0)
-			el->el_flags |= CHARSET_IS_UTF8;
-	}
 
 	if (terminal_init(el) == -1) {
 		el_free(el->el_prog);
@@ -293,7 +289,7 @@
 		void *ptr = va_arg(ap, void *);
 
 		rv = hist_set(el, func, ptr);
-		if (!(el->el_flags & CHARSET_IS_UTF8))
+		if (MB_CUR_MAX == 1)
 			el->el_flags &= ~NARROW_HISTORY;
 		break;
 	}
Index: lib/libedit/read.c
===================================================================
--- lib/libedit/read.c
+++ lib/libedit/read.c
@@ -363,17 +363,6 @@
 				goto again;
 			}
 		case (size_t)-2:
-			/*
-			 * We don't support other multibyte charsets.
-			 * The second condition shouldn't happen
-			 * and is here merely for additional safety.
-			 */
-			if ((el->el_flags & CHARSET_IS_UTF8) == 0 ||
-			    cbp >= MB_LEN_MAX) {
-				errno = EILSEQ;
-				*cp = L'\0';
-				return -1;
-			}
 			/* Incomplete sequence, read another byte. */
 			goto again;
 		default: