From 21adae63bfa4eb22c6d93393bffaa1aeb88b2ecc Mon Sep 17 00:00:00 2001
From: Nikita Smith <git.nikita.smith@gmail.com>
Date: Wed, 11 Feb 2026 00:03:19 -0800
Subject: [PATCH] enable spec-conformant preprocessor in MSVC

---
 build.bat | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/build.bat b/build.bat
index eb0dd4d1..07d1dcec 100644
--- a/build.bat
+++ b/build.bat
@@ -67,7 +67,7 @@ if "%pgo%"=="1" (
 
 :: --- Compile/Link Line Definitions ------------------------------------------
 set cl_common=     /I..\src\ /I..\local\ /nologo /FC /Z7
-set cl_debug=      call cl /Od /Ob1 /DBUILD_DEBUG=1 /D_DEBUG %cl_common% %auto_compile_flags%
+set cl_debug=      call cl /Od /Ob1 /DBUILD_DEBUG=1 /D_DEBUG %cl_common% %auto_compile_flags% /Zc:preprocessor
 set cl_release=    call cl /O2 /DBUILD_DEBUG=0 /DNDEBUG %cl_common% %auto_compile_flags%
 set cl_link=       /link /MANIFEST:EMBED /INCREMENTAL:NO /pdbaltpath:%%%%_PDB%%%% /NATVIS:"%~dp0\src\natvis\base.natvis" /noexp /nocoffgrpinfo /opt:ref /opt:icf
 set cl_out=        /out: