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__
diff --git a/include/__locale b/include/__locale
index 51fada4..3bf617d 100644
--- a/include/__locale
+++ b/include/__locale
@@ -19,7 +19,7 @@
 #include <cstdint>
 #include <cctype>
 #include <locale.h>
-#ifdef _LIBCPP_MSVCRT
+#if defined(_LIBCPP_MSVCRT) || defined(__MINGW32__)
 # include <support/win32/locale_win32.h>
 #elif _AIX
 # include <support/ibm/xlocale.h>
diff --git a/include/algorithm b/include/algorithm
index e3b0882..367489f 100644
--- a/include/algorithm
+++ b/include/algorithm
@@ -631,6 +631,9 @@
 #if defined(__IBMCPP__)
 #include "support/ibm/support.h"
 #endif
+#if defined(_LIBCPP_MSVCRT) || defined(__MINGW32__)
+#include "support/win32/support.h"
+#endif
 
 #include <__undef_min_max>
 
diff --git a/include/cstdio b/include/cstdio
index 1cde3ee..3bc9659 100644
--- a/include/cstdio
+++ b/include/cstdio
@@ -103,6 +103,11 @@
 #pragma GCC system_header
 #endif
 
+// snprintf
+#if defined(_LIBCPP_MSVCRT)
+#include "support/win32/support.h"
+#endif
+
 #ifdef getc
 inline _LIBCPP_INLINE_VISIBILITY int __libcpp_getc(FILE* __stream) {return getc(__stream);}
 #undef getc
diff --git a/include/cwchar b/include/cwchar
index 90eae75..9f51587 100644
--- a/include/cwchar
+++ b/include/cwchar
@@ -106,7 +106,7 @@
 #include <__config>
 #include <cwctype>
 #include <wchar.h>
-#ifdef _LIBCPP_MSVCRT
+#if defined(_LIBCPP_MSVCRT) || defined(__MINGW32__)
 #include <support/win32/support.h> // pull in *swprintf defines
 #endif // _LIBCPP_MSVCRT
 
diff --git a/include/locale b/include/locale
index 5db2566..4dd7737 100644
--- a/include/locale
+++ b/include/locale
@@ -191,7 +191,7 @@
 #endif
 #include <cstdlib>
 #include <ctime>
-#ifdef _LIBCPP_MSVCRT
+#if defined(_LIBCPP_MSVCRT) || defined(__MINGW32__)
 #include <support/win32/locale_win32.h>
 #else // _LIBCPP_MSVCRT
 #include <nl_types.h>
diff --git a/include/support/win32/limits_win32.h b/include/support/win32/limits_win32.h
index 52229c4..a1fad20 100644
--- a/include/support/win32/limits_win32.h
+++ b/include/support/win32/limits_win32.h
@@ -12,16 +12,15 @@
 #define _LIBCPP_SUPPORT_WIN32_LIMITS_WIN32_H
 
 #if !defined(_LIBCPP_MSVCRT)
-#error "This header complements Microsoft's C Runtime library, and should not be included otherwise."
+#error "This header complements the Microsoft C Runtime library, and should not be included otherwise."
 #else
 
-#ifndef NOMINMAX
-#define NOMINMAX
-#endif
-#include <windows.h> // ymath.h works correctly
-
+#include <limits.h> // CHAR_BIT
 #include <float.h> // limit constants
 
+#if ! defined(__clang__)
+#define __CHAR_BIT__       CHAR_BIT
+
 #define __FLT_MANT_DIG__   FLT_MANT_DIG
 #define __FLT_DIG__        FLT_DIG
 #define __FLT_RADIX__      FLT_RADIX
@@ -73,6 +72,7 @@
 #define __builtin_nans(__dummy)  _Snan._Double
 #define __builtin_nansf(__dummy) _FSnan._Float
 #define __builtin_nansl(__dummy) _LSnan._Long_double
+#endif ! defined(__clang__)
 
 #endif // _LIBCPP_MSVCRT
 
diff --git a/include/support/win32/locale_win32.h b/include/support/win32/locale_win32.h
index 019586c..4592755 100644
--- a/include/support/win32/locale_win32.h
+++ b/include/support/win32/locale_win32.h
@@ -15,6 +15,7 @@
 extern "C" unsigned short  __declspec(dllimport) _ctype[];
 
 #include "support/win32/support.h"
+#include <stdio.h>
 #include <memory>
 #include <xlocinfo.h> // _locale_t
 #define locale_t _locale_t
@@ -35,18 +36,18 @@
 locale_t newlocale( int mask, const char * locale, locale_t base );
 locale_t uselocale( locale_t newloc );
 lconv *localeconv_l( locale_t loc );
-size_t mbrlen_l( const char *__restrict__ s, size_t n,
-                 mbstate_t *__restrict__ ps, locale_t loc);
-size_t mbsrtowcs_l( wchar_t *__restrict__ dst, const char **__restrict__ src,
-                    size_t len, mbstate_t *__restrict__ ps, locale_t loc );
-size_t wcrtomb_l( char *__restrict__ s, wchar_t wc, mbstate_t *__restrict__ ps,
+size_t mbrlen_l( const char *__restrict s, size_t n,
+                 mbstate_t *__restrict ps, locale_t loc);
+size_t mbsrtowcs_l( wchar_t *__restrict dst, const char **__restrict src,
+                    size_t len, mbstate_t *__restrict ps, locale_t loc );
+size_t wcrtomb_l( char *__restrict s, wchar_t wc, mbstate_t *__restrict ps,
                   locale_t loc);
-size_t mbrtowc_l( wchar_t *__restrict__ pwc, const char *__restrict__ s,
-                  size_t n, mbstate_t *__restrict__ ps, locale_t loc);
-size_t mbsnrtowcs_l( wchar_t *__restrict__ dst, const char **__restrict__ src,
-                     size_t nms, size_t len, mbstate_t *__restrict__ ps, locale_t loc);
-size_t wcsnrtombs_l( char *__restrict__ dst, const wchar_t **__restrict__ src,
-                     size_t nwc, size_t len, mbstate_t *__restrict__ ps, locale_t loc);
+size_t mbrtowc_l( wchar_t *__restrict pwc, const char *__restrict s,
+                  size_t n, mbstate_t *__restrict ps, locale_t loc);
+size_t mbsnrtowcs_l( wchar_t *__restrict dst, const char **__restrict src,
+                     size_t nms, size_t len, mbstate_t *__restrict ps, locale_t loc);
+size_t wcsnrtombs_l( char *__restrict dst, const wchar_t **__restrict src,
+                     size_t nwc, size_t len, mbstate_t *__restrict ps, locale_t loc);
 wint_t btowc_l( int c, locale_t loc );
 int wctob_l( wint_t c, locale_t loc );
 typedef _VSTD::remove_pointer<locale_t>::type __locale_struct;
@@ -59,7 +60,6 @@
 }
 
 // the *_l functions are prefixed on Windows, only available for msvcr80+, VS2005+
-#include <stdio.h>
 #define mbtowc_l _mbtowc_l
 #define strtoll_l _strtoi64_l
 #define strtoull_l _strtoui64_l
@@ -120,10 +120,10 @@
     return ( c == L' ' || c == L'\t' );
 }
 
-#ifdef _MSC_VER
+#if defined(_LIBCPP_MSVCRT)
 inline int isblank( int c, locale_t /*loc*/ )
 { return ( c == ' ' || c == '\t' ); }
 inline int iswblank( wint_t c, locale_t /*loc*/ )
 { return ( c == L' ' || c == L'\t' ); }
-#endif // _MSC_VER
+#endif // _LIBCPP_MSVCRT
 #endif // _LIBCPP_SUPPORT_WIN32_LOCALE_WIN32_H
diff --git a/include/support/win32/math_win32.h b/include/support/win32/math_win32.h
index 22400c0..c62c54e 100644
--- a/include/support/win32/math_win32.h
+++ b/include/support/win32/math_win32.h
@@ -16,7 +16,9 @@
 #else
 
 #include <math.h>
+#include <float.h> // _FPCLASS_PN etc.
 
+// Necessary?
 typedef float float_t;
 typedef double double_t;
 
diff --git a/include/support/win32/support.h b/include/support/win32/support.h
index 17abb91..b953ab7 100644
--- a/include/support/win32/support.h
+++ b/include/support/win32/support.h
@@ -15,11 +15,16 @@
    Functions and constants used in libc++ that are missing from the Windows C library.
   */
 
-#include <cwchar>  // mbstate_t
+#include <wchar.h>  // mbstate_t
 #include <cstdarg> // va_ macros
 #define swprintf _snwprintf
 #define vswprintf _vsnwprintf
 
+#ifndef NOMINMAX
+#define NOMINMAX
+#endif
+#include <Windows.h>
+
 extern "C" {
 
 int vasprintf( char **sptr, const char *__restrict fmt, va_list ap );