diff --git a/ChangeLog b/ChangeLog
index bd4db65..0181c40 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-08  Brion Vibber  <brion@pobox.com>
+
+	* config.sub (asmjs): Recognize.
+	* testsuite/config-sub.data: Add a test case.
+
 2015-03-06  Ed Schouten  <ed@80386.nl>
 	    Ben Elliston  <bje@gnu.org>
 
diff --git a/config.sub b/config.sub
index 60e3590..8f1229c 100755
--- a/config.sub
+++ b/config.sub
@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2015 Free Software Foundation, Inc.
 
-timestamp='2015-03-06'
+timestamp='2015-03-08'
 
 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -518,6 +518,9 @@ case $basic_machine in
 		basic_machine=i386-pc
 		os=-aros
 		;;
+        asmjs)
+		basic_machine=asmjs-unknown
+		;;
 	aux)
 		basic_machine=m68k-apple
 		os=-aux
diff --git a/testsuite/config-sub.data b/testsuite/config-sub.data
index 75387a8..ae95c23 100644
--- a/testsuite/config-sub.data
+++ b/testsuite/config-sub.data
@@ -37,6 +37,7 @@ armv7-unknown-netbsdelf7.0-eabi	armv7-unknown-netbsdelf7.0-eabi
 armv7-unknown-netbsdelf7.0-eabihf	armv7-unknown-netbsdelf7.0-eabihf
 armv8b-linux-gnueabi		armv8b-unknown-linux-gnueabi
 aros				i386-pc-aros
+asmjs				asmjs-unknown-none
 avr32				avr32-unknown-none
 avr32-linux			avr32-unknown-linux-gnu
 be32-none			be32-unknown-none