[clang] Enable c++20 modules support for c++23preview in clang-cl (PR #173663)

[via cfe-commits]

https://github.com/waruqi updated https://github.com/llvm/llvm-project/pull/173663

>From 1010718f88a507b1189d06d4226453b9fdb8f30f Mon Sep 17 00:00:00 2001
From: ruki <waruqi at gmail.com>
Date: Fri, 26 Dec 2025 21:33:48 +0800
Subject: [PATCH] Enable c++20 modules support for c++23preview in clang-cl

---
 clang/lib/Driver/ToolChains/Clang.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 310f3b58a211e..b021b27ebd7a4 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -7221,6 +7221,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
        Std->containsValue("c++20") || Std->containsValue("gnu++20") ||
        Std->containsValue("c++2b") || Std->containsValue("gnu++2b") ||
        Std->containsValue("c++23") || Std->containsValue("gnu++23") ||
+       Std->containsValue("c++23preview") ||
        Std->containsValue("c++2c") || Std->containsValue("gnu++2c") ||
        Std->containsValue("c++26") || Std->containsValue("gnu++26") ||
        Std->containsValue("c++latest") || Std->containsValue("gnu++latest"));