etc/NEWS: Add entry for new `switch' bytecode.

diff --git a/etc/NEWS b/etc/NEWS
index 32137a79da6170a249ca14a92e55db2e92ecfe8f..f0df0a70caaa6941522ae3219705341926ceaff4 100644 (file)
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -741,6 +741,12 @@ processes on exit.
 \f
 * Incompatible Lisp Changes in Emacs 26.1
 
++++
+** Certain cond/pcase/cl-case forms are now compiled using a faster jump
+table implementation. This uses a new bytecode op `switch', which isn't
+compatible with previous Emacs versions. This functionality can be disabled
+by setting `byte-compile-cond-use-jump-table' to nil.
+
 +++
 ** Resizing a frame no longer runs 'window-configuration-change-hook'.
 Put your function on 'window-size-change-functions' instead.