diff --git a/runtime/syntax/c.vim b/runtime/syntax/c.vim
index 68b6778c7..d2f2b85b4 100644
--- a/runtime/syntax/c.vim
+++ b/runtime/syntax/c.vim
@@ -1,7 +1,7 @@
" Vim syntax file
" Language: C
" Maintainer: The Vim Project <https://github.com/vim/vim>
-" Last Change: 2025 Jan 18
+" Last Change: 2025 Nov 18
" Former Maintainer: Bram Moolenaar <Br...@vim.org>
" Quit when a (custom) syntax file was already loaded
@@ -421,8 +421,10 @@ if !exists("c_no_ansi") || exists("c_ansi_constants") || exists("c_gnu")
syn keyword cConstant NDEBUG
" POSIX 2001
syn keyword cConstant SIGBUS SIGPOLL SIGPROF SIGSYS SIGURG SIGVTALRM SIGXCPU SIGXFSZ
+ " POSIX Issue 8 (post 2017)
+ syn keyword cConstant SIGWINCH
" non-POSIX signals
- syn keyword cConstant SIGWINCH SIGINFO
+ syn keyword cConstant SIGINFO SIGIO
" Add POSIX errors as well. List comes from:
" http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html syn keyword cConstant E2BIG EACCES EADDRINUSE EADDRNOTAVAIL EAFNOSUPPORT EAGAIN EALREADY EBADF