[MinGW] Allow using LTO when lld is used as linker

Differential Revision: https://reviews.llvm.org/D53195

llvm-svn: 344412
diff --git a/clang/lib/Driver/ToolChains/MinGW.h b/clang/lib/Driver/ToolChains/MinGW.h
index 450044d..04d2300 100644
--- a/clang/lib/Driver/ToolChains/MinGW.h
+++ b/clang/lib/Driver/ToolChains/MinGW.h
@@ -59,6 +59,8 @@
   MinGW(const Driver &D, const llvm::Triple &Triple,
         const llvm::opt::ArgList &Args);
 
+  bool HasNativeLLVMSupport() const override;
+
   bool IsIntegratedAssemblerDefault() const override;
   bool IsUnwindTablesDefault(const llvm::opt::ArgList &Args) const override;
   bool isPICDefault() const override;
@@ -99,6 +101,8 @@
   void findGccLibDir();
   llvm::ErrorOr<std::string> findGcc();
   llvm::ErrorOr<std::string> findClangRelativeSysroot();
+
+  bool NativeLLVMSupport;
 };
 
 } // end namespace toolchains