From 07b90f9ec1c999aebb99771f6877adb92dace4e6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment?= <git@drawbu.dev>
Date: Thu, 1 Oct 2026 11:23:56 +0200
Subject: [PATCH] xml-security-c: fix build with gcc 16

nixpkgs now defaults to gcc16, which defaults to gnu++20 standard.

Upstream needs to be patched, but in the meantime we can just use an older
standard.
---
 pkgs/by-name/xm/xml-security-c/package.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pkgs/by-name/xm/xml-security-c/package.nix b/pkgs/by-name/xm/xml-security-c/package.nix
index 74be5b66d8aa..e2c30a920d5c 100644
--- a/pkgs/by-name/xm/xml-security-c/package.nix
+++ b/pkgs/by-name/xm/xml-security-c/package.nix
@@ -27,6 +27,8 @@ stdenv.mkDerivation (finalAttrs: {
     "--with-xalan"
   ];
 
+  env.CXXFLAGS = "-std=gnu++17";
+
   nativeBuildInputs = [
     autoreconfHook
     pkg-config