Update runtime files.
diff --git a/runtime/syntax/zsh.vim b/runtime/syntax/zsh.vim
index b4efcdc..3eba438 100644
--- a/runtime/syntax/zsh.vim
+++ b/runtime/syntax/zsh.vim
@@ -2,7 +2,7 @@
 " Language:             Zsh shell script
 " Maintainer:           Christian Brabandt <cb@256bit.org>
 " Previous Maintainer:  Nikolai Weibull <now@bitwi.se>
-" Latest Revision:      2017-11-22
+" Latest Revision:      2018-05-12
 " License:              Vim (see :h license)
 " Repository:           https://github.com/chrisbra/vim-zsh
 
@@ -67,15 +67,15 @@
 syn region  zshHereDoc          matchgroup=zshRedir
                                 \ start='<\@<!<<\s*\z([^<]\S*\)'
                                 \ end='^\z1\>'
-                                \ contains=@zshSubst
+                                \ contains=@zshSubst,@zshDerefs,zshQuoted,zshPOSIXString
 syn region  zshHereDoc          matchgroup=zshRedir
                                 \ start='<\@<!<<\s*\\\z(\S\+\)'
                                 \ end='^\z1\>'
-                                \ contains=@zshSubst
+                                \ contains=@zshSubst,@zshDerefs,zshQuoted,zshPOSIXString
 syn region  zshHereDoc          matchgroup=zshRedir
                                 \ start='<\@<!<<-\s*\\\=\z(\S\+\)'
                                 \ end='^\s*\z1\>'
-                                \ contains=@zshSubst
+                                \ contains=@zshSubst,@zshDerefs,zshQuoted,zshPOSIXString
 syn region  zshHereDoc          matchgroup=zshRedir
                                 \ start=+<\@<!<<\s*\(["']\)\z(\S\+\)\1+
                                 \ end='^\z1\>'
@@ -118,8 +118,8 @@
                                 \ ttyctl type ulimit umask unalias unfunction
                                 \ unhash unlimit unset  vared wait
                                 \ whence where which zcompile zformat zftp zle
-                                \ zmodload zparseopts zprof zpty zregexparse
-                                \ zsocket zstyle ztcp
+                                \ zmodload zparseopts zprof zpty zrecompile
+                                \ zregexparse zsocket zstyle ztcp
 
 " Options, generated by: echo ${(j:\n:)options[(I)*]} | sort
 " Create a list of option names from zsh source dir: