[llvm] [gn build] Manually partially port #108276 (PR #149595)

[Arthur Eubanks via llvm-commits]

https://github.com/aeubanks created https://github.com/llvm/llvm-project/pull/149595

Fixes windows gn clang build.

Don't worry about exporting clang symbols on windows in gn build for now.

>From 361f59888a6dab93bd61dee75f195d9fd823a911 Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeubanks at google.com>
Date: Fri, 18 Jul 2025 21:28:39 +0000
Subject: [PATCH] [gn build] Manually partially port #108276

Fixes windows gn clang build.

Don't worry about exporting clang symbols on windows in gn build for now.
---
 llvm/utils/gn/build/BUILD.gn | 1 +
 1 file changed, 1 insertion(+)

diff --git a/llvm/utils/gn/build/BUILD.gn b/llvm/utils/gn/build/BUILD.gn
index 9b5254e4c9f0b..f080a4c64c37d 100644
--- a/llvm/utils/gn/build/BUILD.gn
+++ b/llvm/utils/gn/build/BUILD.gn
@@ -179,6 +179,7 @@ config("compiler_defaults") {
       "_HAS_EXCEPTIONS=0",
       "_UNICODE",
       "UNICODE",
+      "CLANG_BUILD_STATIC",
     ]
     cflags += [ "/EHs-c-" ]
     cflags_cc += [ "/std:c++17" ]