diff --git a/runtime/ftplugin/tex.vim b/runtime/ftplugin/tex.vim
index 4089927..1147001 100644
--- a/runtime/ftplugin/tex.vim
+++ b/runtime/ftplugin/tex.vim
@@ -41,5 +41,6 @@
 endif " exists("loaded_matchit")
 
 let &cpo = s:save_cpo
+unlet s:save_cpo
 
 " vim:sts=2:sw=2: