[LLVM][Clang][Cygwin] Fix Cygwin builds

clang/include/clang/Support/Compiler.h

@@ -50,7 +50,7 @@
 #define CLANG_EXPORT_TEMPLATE
 #endif
 #elif defined(__ELF__) || defined(__MINGW32__) || defined(_AIX) ||             \
-    defined(__MVS__)
+    defined(__MVS__) || defined(__CYGWIN__)
 #define CLANG_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define CLANG_TEMPLATE_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define CLANG_EXPORT_TEMPLATE

clang/lib/AST/ItaniumCXXABI.cpp

@@ -236,8 +236,7 @@ class ItaniumCXXABI : public CXXABI {
 
   CallingConv getDefaultMethodCallConv(bool isVariadic) const override {
     const llvm::Triple &T = Context.getTargetInfo().getTriple();
-    if (!isVariadic && T.isWindowsGNUEnvironment() &&
-        T.getArch() == llvm::Triple::x86)
+    if (!isVariadic && T.isOSCygMing() && T.getArch() == llvm::Triple::x86)
       return CC_X86ThisCall;
     return Context.getTargetInfo().getDefaultCallingConv();
   }

clang/lib/AST/RecordLayoutBuilder.cpp

@@ -1950,7 +1950,7 @@ void ItaniumRecordLayoutBuilder::LayoutField(const FieldDecl *D,
           // silently there. For other targets that have ms_struct enabled
           // (most probably via a pragma or attribute), trigger a diagnostic
           // that defaults to an error.
-          if (!Context.getTargetInfo().getTriple().isWindowsGNUEnvironment())
+          if (!Context.getTargetInfo().getTriple().isOSCygMing())
             Diag(D->getLocation(), diag::warn_npot_ms_struct);
         }
         if (TypeSize > FieldAlign &&

clang/lib/Basic/Targets/X86.h

@@ -948,7 +948,6 @@ 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,

clang/lib/CodeGen/CodeGenModule.cpp

@@ -1680,7 +1680,7 @@ static bool shouldAssumeDSOLocal(const CodeGenModule &CGM,
 
   const llvm::Triple &TT = CGM.getTriple();
   const auto &CGOpts = CGM.getCodeGenOpts();
-  if (TT.isWindowsGNUEnvironment()) {
+  if (TT.isOSCygMing()) {
     // In MinGW, variables without DLLImport can still be automatically
     // imported from a DLL by the linker; don't mark variables that
     // potentially could come from another DLL as DSO local.

clang/lib/CodeGen/ItaniumCXXABI.cpp

@@ -3757,7 +3757,7 @@ static bool ShouldUseExternalRTTIDescriptor(CodeGenModule &CGM,
     bool IsDLLImport = RD->hasAttr<DLLImportAttr>();
 
     // Don't import the RTTI but emit it locally.
-    if (CGM.getTriple().isWindowsGNUEnvironment())
+    if (CGM.getTriple().isOSCygMing())
       return false;
 
     if (CGM.getVTables().isVTableExternal(RD)) {
@@ -4044,10 +4044,7 @@ static llvm::GlobalVariable::LinkageTypes getTypeInfoLinkage(CodeGenModule &CGM,
           return llvm::GlobalValue::ExternalLinkage;
       // MinGW always uses LinkOnceODRLinkage for type info.
       if (RD->isDynamicClass() &&
-          !CGM.getContext()
-               .getTargetInfo()
-               .getTriple()
-               .isWindowsGNUEnvironment())
+          !CGM.getContext().getTargetInfo().getTriple().isOSCygMing())
         return CGM.getVTableLinkage(RD);
     }
 

clang/lib/CodeGen/Targets/X86.cpp

@@ -1391,7 +1391,7 @@ class WinX86_64ABIInfo : public ABIInfo {
 public:
   WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, X86AVXABILevel AVXLevel)
       : ABIInfo(CGT), AVXLevel(AVXLevel),
-        IsMingw64(getTarget().getTriple().isWindowsGNUEnvironment()) {}
+        IsMingw64(getTarget().getTriple().isOSCygMing()) {}
 
   void computeInfo(CGFunctionInfo &FI) const override;
 

clang/lib/Driver/ToolChain.cpp

@@ -744,9 +744,7 @@ std::string ToolChain::buildCompilerRTBasename(const llvm::opt::ArgList &Args,
     Suffix = IsITANMSVCWindows ? ".lib" : ".a";
     break;
   case ToolChain::FT_Shared:
-    Suffix = TT.isOSWindows()
-                 ? (TT.isWindowsGNUEnvironment() ? ".dll.a" : ".lib")
-                 : ".so";
+    Suffix = TT.isOSWindows() ? (TT.isOSCygMing() ? ".dll.a" : ".lib") : ".so";
     break;
   }
 

clang/lib/Sema/SemaDecl.cpp

@@ -12536,7 +12536,7 @@ static bool isDefaultStdCall(FunctionDecl *FD, Sema &S) {
 
   // Default calling convention for MinGW is __cdecl
   const llvm::Triple &T = S.Context.getTargetInfo().getTriple();
-  if (T.isWindowsGNUEnvironment())
+  if (T.isOSCygMing())
     return false;
 
   // Default calling convention for WinMain, wWinMain and DllMain

clang/lib/Sema/SemaDeclCXX.cpp

@@ -6272,7 +6272,7 @@ static void ReferenceDllExportedMembers(Sema &S, CXXRecordDecl *Class) {
     }
   } MarkingDllexportedContext(S, Class, ClassAttr->getLocation());
 
-  if (S.Context.getTargetInfo().getTriple().isWindowsGNUEnvironment())
+  if (S.Context.getTargetInfo().getTriple().isOSCygMing())
     S.MarkVTableUsed(Class->getLocation(), Class, true);
 
   for (Decl *Member : Class->decls()) {
@@ -6574,7 +6574,7 @@ void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
   // declarations, except in MinGW mode.
   if (ClassExported && !ClassAttr->isInherited() &&
       TSK == TSK_ExplicitInstantiationDeclaration &&
-      !Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) {
+      !Context.getTargetInfo().getTriple().isOSCygMing()) {
     Class->dropAttr<DLLExportAttr>();
     return;
   }

clang/lib/Sema/SemaTemplate.cpp

@@ -8889,8 +8889,7 @@ Sema::CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
         // The declaration itself has not actually been instantiated, so it is
         // still okay to specialize it.
         StripImplicitInstantiation(
-            PrevDecl,
-            Context.getTargetInfo().getTriple().isWindowsGNUEnvironment());
+            PrevDecl, Context.getTargetInfo().getTriple().isOSCygMing());
         return false;
       }
       // Fall through
@@ -9758,7 +9757,7 @@ DeclResult Sema::ActOnExplicitInstantiation(
                                        : TSK_ExplicitInstantiationDeclaration;
 
   if (TSK == TSK_ExplicitInstantiationDeclaration &&
-      !Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) {
+      !Context.getTargetInfo().getTriple().isOSCygMing()) {
     // Check for dllexport class template instantiation declarations,
     // except for MinGW mode.
     for (const ParsedAttr &AL : Attr) {
@@ -9823,7 +9822,7 @@ DeclResult Sema::ActOnExplicitInstantiation(
     = PrevDecl ? PrevDecl->getTemplateSpecializationKind() : TSK_Undeclared;
 
   if (TSK == TSK_ExplicitInstantiationDefinition && PrevDecl != nullptr &&
-      Context.getTargetInfo().getTriple().isWindowsGNUEnvironment()) {
+      Context.getTargetInfo().getTriple().isOSCygMing()) {
     // Check for dllexport class template instantiation definitions in MinGW
     // mode, if a previous declaration of the instantiation was seen.
     for (const ParsedAttr &AL : Attr) {
@@ -9991,7 +9990,7 @@ DeclResult Sema::ActOnExplicitInstantiation(
     // In MinGW mode, export the template instantiation if the declaration
     // was marked dllexport.
     if (PrevDecl_TSK == TSK_ExplicitInstantiationDeclaration &&
-        Context.getTargetInfo().getTriple().isWindowsGNUEnvironment() &&
+        Context.getTargetInfo().getTriple().isOSCygMing() &&
         PrevDecl->hasAttr<DLLExportAttr>()) {
       dllExportImportClassTemplateSpecialization(*this, Def);
     }

llvm/cmake/modules/AddLLVM.cmake

@@ -666,7 +666,7 @@ function(llvm_add_library name)
     # When building shared objects for each target there are some internal APIs
     # that are used across shared objects which we can't hide.
     if (LLVM_BUILD_LLVM_DYLIB_VIS AND NOT BUILD_SHARED_LIBS AND NOT APPLE AND
-        (NOT (WIN32 OR CYGWIN) OR (MINGW AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
+        (NOT (WIN32 OR CYGWIN) OR ((MINGW OR CYGWIN) AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
         NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX") AND
         NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
 

llvm/include/llvm/Support/Compiler.h

@@ -129,7 +129,7 @@
 #endif
 
 #if (!(defined(_WIN32) || defined(__CYGWIN__)) ||                              \
-     (defined(__MINGW32__) && defined(__clang__)))
+     ((defined(__MINGW32__) || defined(__CYGWIN__)) && defined(__clang__)))
 #define LLVM_LIBRARY_VISIBILITY LLVM_ATTRIBUTE_VISIBILITY_HIDDEN
 // Clang compilers older then 15 do not support gnu style attributes on
 // namespaces.
@@ -198,7 +198,7 @@
 #endif
 #define LLVM_ABI_EXPORT __declspec(dllexport)
 #elif defined(__ELF__) || defined(__MINGW32__) || defined(_AIX) ||             \
-    defined(__MVS__)
+    defined(__MVS__) || defined(__CYGWIN__)
 #define LLVM_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define LLVM_TEMPLATE_ABI LLVM_ATTRIBUTE_VISIBILITY_DEFAULT
 #define LLVM_EXPORT_TEMPLATE

llvm/lib/Target/CMakeLists.txt

@@ -22,7 +22,7 @@ add_llvm_component_library(LLVMTarget
 # When building shared objects for each target there are some internal APIs
 # that are used across shared objects which we can't hide.
 if (NOT BUILD_SHARED_LIBS AND NOT APPLE AND
-    (NOT (WIN32 OR CYGWIN) OR (MINGW AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
+    (NOT (WIN32 OR CYGWIN) OR ((MINGW OR CYGWIN) AND CMAKE_CXX_COMPILER_ID MATCHES "Clang")) AND
     NOT (${CMAKE_SYSTEM_NAME} MATCHES "AIX") AND
     NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
   # Set default visibility to hidden, so we don't export all the Target classes

llvm/tools/llvm-shlib/CMakeLists.txt

@@ -66,11 +66,11 @@ if(LLVM_BUILD_LLVM_DYLIB)
     else()
       # GNU ld doesn't resolve symbols in the version script.
       set(LIB_NAMES -Wl,--whole-archive ${LIB_NAMES} -Wl,--no-whole-archive)
-      if (NOT LLVM_LINKER_IS_SOLARISLD AND NOT MINGW)
+      if (NOT LLVM_LINKER_IS_SOLARISLD AND NOT (MINGW OR CYGWIN))
         # Solaris ld does not accept global: *; so there is no way to version *all* global symbols
         set(LIB_NAMES -Wl,--version-script,${LLVM_LIBRARY_DIR}/tools/llvm-shlib/simple_version_script.map ${LIB_NAMES})
       endif()
-      if (NOT MINGW AND NOT LLVM_LINKER_IS_SOLARISLD_ILLUMOS)
+      if (NOT (MINGW OR CYGWIN) AND NOT LLVM_LINKER_IS_SOLARISLD_ILLUMOS)
         # Optimize function calls for default visibility definitions to avoid PLT and
         # reduce dynamic relocations.
         # Note: for -fno-pic default, the address of a function may be different from