Index: lib/Driver/MinGWToolChain.cpp
===================================================================
--- lib/Driver/MinGWToolChain.cpp
+++ lib/Driver/MinGWToolChain.cpp
@@ -62,20 +62,27 @@
   }
 }
 
+llvm::ErrorOr<std::string> MinGW::findGcc() {
+  llvm::SmallVector<llvm::SmallString<32>, 2> Gccs;
+  Gccs.emplace_back(getTriple().getArchName());
+  Gccs[0] += "-w64-mingw32-gcc";
+  Gccs.emplace_back("mingw32-gcc");
+  for (StringRef CandidateGcc : Gccs)
+    if (llvm::ErrorOr<std::string> GPPName = llvm::sys::findProgramByName(CandidateGcc))
+      return GPPName;
+  return make_error_code(std::errc::no_such_file_or_directory);
+}
+
 MinGW::MinGW(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
     : ToolChain(D, Triple, Args) {
   getProgramPaths().push_back(getDriver().getInstalledDir());
 
-  // On Windows if there is no sysroot we search for gcc on the PATH.
   if (getDriver().SysRoot.size())
-  Base = getDriver().SysRoot;
-#ifdef LLVM_ON_WIN32
-  else if (llvm::ErrorOr<std::string> GPPName =
-               llvm::sys::findProgramByName("gcc"))
+    Base = getDriver().SysRoot;
+  else if (llvm::ErrorOr<std::string> GPPName = findGcc())
     Base = llvm::sys::path::parent_path(
         llvm::sys::path::parent_path(GPPName.get()));
-#endif
-  if (!Base.size())
+  else
     Base = llvm::sys::path::parent_path(getDriver().getInstalledDir());
 
   Base += llvm::sys::path::get_separator();
Index: lib/Driver/ToolChains.h
===================================================================
--- lib/Driver/ToolChains.h
+++ lib/Driver/ToolChains.h
@@ -662,6 +662,7 @@
   mutable std::unique_ptr<tools::gcc::Preprocessor> Preprocessor;
   mutable std::unique_ptr<tools::gcc::Compiler> Compiler;
   void findGccLibDir();
+  llvm::ErrorOr<std::string> findGcc();
 };
 
 class LLVM_LIBRARY_VISIBILITY OpenBSD : public Generic_ELF {