[clang] [Cygwin] Cygwin basic support (PR #74868)

[徐持恒 Xu Chiheng via cfe-commits]

https://github.com/xu-chiheng created https://github.com/llvm/llvm-project/pull/74868

None

>From 680b2b48925d52c006eee5f26b1173856dfcf376 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=BE=90=E6=8C=81=E6=81=92=20Xu=20Chiheng?=
 <chiheng.xu at gmail.com>
Date: Sat, 9 Dec 2023 00:59:00 +0800
Subject: [PATCH] [Cygwin] Cygwin basic support

---
 clang/lib/Basic/Targets/X86.h         | 5 ++++-
 clang/lib/Driver/ToolChains/Clang.cpp | 4 +++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Basic/Targets/X86.h b/clang/lib/Basic/Targets/X86.h
index 0ab1c10833db26..e77e1e690cfc0c 100644
--- a/clang/lib/Basic/Targets/X86.h
+++ b/clang/lib/Basic/Targets/X86.h
@@ -905,7 +905,6 @@ class LLVM_LIBRARY_VISIBILITY CygwinX86_64TargetInfo : public X86_64TargetInfo {
   CygwinX86_64TargetInfo(const llvm::Triple &Triple, const TargetOptions &Opts)
       : X86_64TargetInfo(Triple, Opts) {
     this->WCharType = TargetInfo::UnsignedShort;
-    TLSSupported = false;
   }
 
   void getTargetDefines(const LangOptions &Opts,
@@ -919,6 +918,10 @@ class LLVM_LIBRARY_VISIBILITY CygwinX86_64TargetInfo : public X86_64TargetInfo {
     if (Opts.CPlusPlus)
       Builder.defineMacro("_GNU_SOURCE");
   }
+
+  BuiltinVaListKind getBuiltinVaListKind() const override {
+    return TargetInfo::CharPtrBuiltinVaList;
+  }
 };
 
 class LLVM_LIBRARY_VISIBILITY DarwinX86_64TargetInfo
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index eb26bfade47b7a..8b38c9e386d76e 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -6656,7 +6656,9 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   // -fuse-cxa-atexit is default.
   if (!Args.hasFlag(
           options::OPT_fuse_cxa_atexit, options::OPT_fno_use_cxa_atexit,
-          !RawTriple.isOSAIX() && !RawTriple.isOSWindows() &&
+          !RawTriple.isOSAIX()
+          && !RawTriple.isWindowsGNUEnvironment()
+          && !RawTriple.isWindowsMSVCEnvironment() &&
               ((RawTriple.getVendor() != llvm::Triple::MipsTechnologies) ||
                RawTriple.hasEnvironment())) ||
       KernelOrKext)