G M: Restore the ability for libcxx to compile again on mingw 64.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@190837 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/__config b/include/__config
index eef8c78..4d79d7f 100644
--- a/include/__config
+++ b/include/__config
@@ -80,7 +80,10 @@
# if defined(_MSC_VER) && !defined(__clang__)
# define _LIBCPP_MSVC // Using Microsoft Visual C++ compiler
# endif
-# define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
+# // If mingw not explicitly detected, assume using MS C runtime only.
+# ifndef __MINGW32__
+# define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
+# endif
#endif // _WIN32
#ifdef __linux__