diff --git a/libguile/instructions.c b/libguile/instructions.c
index 29e60983b..a38035d25 100644
--- a/libguile/instructions.c
+++ b/libguile/instructions.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
+/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013, 2017 Free Software Foundation, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public License
@@ -65,7 +65,8 @@ SCM_SYMBOL (sym_bang, "!");
     M(B1_X7_C24)                                \
     M(B1_X7_S24)                                \
     M(B1_X7_F24)                                \
-    M(B1_X31)
+    M(B1_X31)                                   \
+    M(C16_C16)
 
 #define TYPE_WIDTH 6
 
diff --git a/module/language/bytecode.scm b/module/language/bytecode.scm
index c140b4bb3..e25e8c923 100644
--- a/module/language/bytecode.scm
+++ b/module/language/bytecode.scm
@@ -1,6 +1,6 @@
 ;;; Bytecode
 
-;; Copyright (C) 2013 Free Software Foundation, Inc.
+;; Copyright (C) 2013, 2017 Free Software Foundation, Inc.
 
 ;;;; This library is free software; you can redistribute it and/or
 ;;;; modify it under the terms of the GNU Lesser General Public
@@ -58,6 +58,7 @@
       ((L32) 1)
       ((LO32) 1)
       ((C8_C24) 2)
+      ((C16_C16) 2)
       ((B1_C7_L24) 3)
       ((B1_X7_S24) 2)
       ((B1_X7_F24) 2)
diff --git a/module/system/vm/assembler.scm b/module/system/vm/assembler.scm
index 1eb253f65..89b740762 100644
--- a/module/system/vm/assembler.scm
+++ b/module/system/vm/assembler.scm
@@ -1,6 +1,6 @@
 ;;; Guile bytecode assembler
 
-;;; Copyright (C) 2001, 2009, 2010, 2012, 2013, 2014, 2015 Free Software Foundation, Inc.
+;;; Copyright (C) 2001, 2009, 2010, 2012, 2013, 2014, 2015, 2017 Free Software Foundation, Inc.
 ;;;
 ;;; This library is free software; you can redistribute it and/or
 ;;; modify it under the terms of the GNU Lesser General Public
@@ -278,6 +278,11 @@
         (y (check-srange y #xffffff)))
     (logior x (ash y 8))))
 
+(define-inline (pack-u16-u16 x y)
+  (let ((x (check-urange x #xffff))
+        (y (check-urange y #xffff)))
+    (logior x (ash y 16))))
+
 (define-inline (pack-u1-u7-u24 x y z)
   (let ((x (check-urange x #x1))
         (y (check-urange y #x7f))
@@ -621,6 +626,8 @@ later by the linker."
           (emit asm 0))
          ((C8_C24 a b)
           (emit asm (pack-u8-u24 a b)))
+         ((C16_C16 a b)
+          (emit asm (pack-u16-u16 a b)))
          ((B1_X7_L24 a label)
           (record-label-reference asm label)
           (emit asm (pack-u1-u7-u24 (if a 1 0) 0 0)))
@@ -852,6 +859,7 @@ later by the linker."
           ('L32 #'(label))
           ('LO32 #'(label offset))
           ('C8_C24 #'(a b))
+          ('C16_C16 #'(a b))
           ('B1_X7_L24 #'(a label))
           ('B1_C7_L24 #'(a b label))
           ('B1_X31 #'(a))
diff --git a/module/system/vm/disassembler.scm b/module/system/vm/disassembler.scm
index 4db4a033d..0ab8c6bf9 100644
--- a/module/system/vm/disassembler.scm
+++ b/module/system/vm/disassembler.scm
@@ -1,6 +1,6 @@
 ;;; Guile bytecode disassembler
 
-;;; Copyright (C) 2001, 2009, 2010, 2012, 2013, 2014, 2015 Free Software Foundation, Inc.
+;;; Copyright (C) 2001, 2009, 2010, 2012, 2013, 2014, 2015, 2017 Free Software Foundation, Inc.
 ;;;
 ;;; This library is free software; you can redistribute it and/or
 ;;; modify it under the terms of the GNU Lesser General Public
@@ -115,6 +115,9 @@
           ((C8_C24)
            #'((logand word #xff)
               (ash word -8)))
+          ((C16_C16)
+           #'((logand word #xffff)
+              (ash word -16)))
           ((B1_C7_L24)
            #'((not (zero? (logand word #x1)))
               (logand (ash word -1) #x7f)