diff -Naur Python-3.7.0-orig/configure.ac Python-3.7.0/configure.ac
--- Python-3.7.0-orig/configure.ac	2018-07-12 10:20:53.635104900 +0300
+++ Python-3.7.0/configure.ac	2018-07-12 10:20:53.947105500 +0300
@@ -561,6 +561,14 @@
   AC_DEFINE(_INCLUDE__STDC_A1_SOURCE, 1, Define to include mbstate_t for mbrtowc)
 fi
 
+AC_MSG_CHECKING([for init system calls])
+AC_SUBST(INITSYS)
+case $host in
+  *-*-mingw*)	INITSYS=nt;;
+  *)		INITSYS=posix;;
+esac
+AC_MSG_RESULT([$INITSYS])
+
 # Record the configure-time value of MACOSX_DEPLOYMENT_TARGET,
 # it may influence the way we can build extensions, so distutils
 # needs to check it
diff -Naur Python-3.7.0-orig/Modules/posixmodule.c Python-3.7.0/Modules/posixmodule.c
--- Python-3.7.0-orig/Modules/posixmodule.c	2018-06-27 06:07:35.000000000 +0300
+++ Python-3.7.0/Modules/posixmodule.c	2018-07-12 10:20:53.947105500 +0300
@@ -173,6 +173,27 @@
 #define HAVE_CWAIT      1
 #define HAVE_FSYNC      1
 #define fsync _commit
+#elif defined(__MINGW32__)	/* GCC for windows hosts */
+/* getlogin is detected by configure on mingw-w64 */
+#undef HAVE_GETLOGIN
+/*#define HAVE_GETCWD	1 - detected by configure*/
+#define HAVE_GETPPID    1
+#define HAVE_GETLOGIN   1
+#define HAVE_SPAWNV	1
+#define HAVE_WSPAWNV    1
+#define HAVE_WEXECV    1
+/*#define HAVE_EXECV	1 - detected by configure*/
+#define HAVE_PIPE	1
+#define HAVE_POPEN	1
+#define HAVE_SYSTEM	1
+#define HAVE_CWAIT	1
+#define HAVE_FSYNC	1
+#define fsync _commit
+#include <windows.h>
+#include <winioctl.h>
+#ifndef _MAX_ENV
+#define _MAX_ENV	32767
+#endif
 #else
 /* Unix functions that the configure script doesn't check for */
 #define HAVE_EXECV      1
@@ -289,7 +310,7 @@
 #endif
 #endif
 
-#ifdef _MSC_VER
+#ifdef MS_WINDOWS
 #ifdef HAVE_DIRECT_H
 #include <direct.h>
 #endif
@@ -1297,7 +1318,7 @@
 */
 #include <crt_externs.h>
 static char **environ;
-#elif !defined(_MSC_VER) && ( !defined(__WATCOMC__) || defined(__QNX__) )
+#elif !defined(MS_WINDOWS) && ( !defined(__WATCOMC__) || defined(__QNX__) )
 extern char **environ;
 #endif /* !_MSC_VER */
 
diff -Naur Python-3.7.0-orig/Modules/Setup.config.in Python-3.7.0/Modules/Setup.config.in
--- Python-3.7.0-orig/Modules/Setup.config.in	2018-07-12 10:20:43.495087100 +0300
+++ Python-3.7.0/Modules/Setup.config.in	2018-07-12 10:20:53.962705500 +0300
@@ -3,3 +3,6 @@
 # The purpose of this file is to conditionally enable certain modules
 # based on configure-time options.
 
+# init system calls(posix/nt/...) for INITFUNC (used by makesetup)
+@INITSYS@ -DPy_BUILD_CORE posixmodule.c # system calls
+
diff -Naur Python-3.7.0-orig/Modules/Setup.dist Python-3.7.0/Modules/Setup.dist
--- Python-3.7.0-orig/Modules/Setup.dist	2018-06-27 06:07:35.000000000 +0300
+++ Python-3.7.0/Modules/Setup.dist	2018-07-12 10:20:53.978305500 +0300
@@ -104,7 +104,6 @@
 # This only contains the minimal set of modules required to run the
 # setup.py script in the root of the Python source tree.
 
-posix -DPy_BUILD_CORE posixmodule.c	# posix (UNIX) system calls
 errno errnomodule.c			# posix (UNIX) errno values
 pwd pwdmodule.c				# this is needed to find out the user's home dir
 					# if $HOME is not set