Updated runtime files.
diff --git a/runtime/syntax/c.vim b/runtime/syntax/c.vim
index 3fe3256..57d99ab 100644
--- a/runtime/syntax/c.vim
+++ b/runtime/syntax/c.vim
@@ -1,7 +1,7 @@
 " Vim syntax file
 " Language:	C
 " Maintainer:	Bram Moolenaar <Bram@vim.org>
-" Last Change:	2016 Apr 10
+" Last Change:	2016 Jul 07
 
 " Quit when a (custom) syntax file was already loaded
 if exists("b:current_syntax")
@@ -295,7 +295,7 @@
   syn keyword cConstant SCHAR_MIN SINT_MIN SLONG_MIN SSHRT_MIN
   syn keyword cConstant SCHAR_MAX SINT_MAX SLONG_MAX SSHRT_MAX
   if !exists("c_no_c99")
-    syn keyword cConstant __func__
+    syn keyword cConstant __func__ __VA_ARGS__
     syn keyword cConstant LLONG_MIN LLONG_MAX ULLONG_MAX
     syn keyword cConstant INT8_MIN INT16_MIN INT32_MIN INT64_MIN
     syn keyword cConstant INT8_MAX INT16_MAX INT32_MAX INT64_MAX