From: Roumen Petrov <local@example.net>
Date: Sat, 23 Feb 2013 13:54:02 +0200

Issue #17592: MINGW: configure MACHDEP and platform for build

diff -r 3f921c3b1e87 Python/getplatform.c
--- a/Python/getplatform.c	Fri Mar 11 22:53:15 2016 +0100
+++ b/Python/getplatform.c	Sun Mar 13 02:26:06 2016 +0000
@@ -1,6 +1,12 @@
 
 #include "Python.h"
 
+#ifdef __MINGW32__
+#  undef PLATFORM
+/* see PC/pyconfig.h */
+#  define PLATFORM "win32"
+#endif
+
 #ifndef PLATFORM
 #define PLATFORM "unknown"
 #endif
diff -r 3f921c3b1e87 configure.ac
--- a/configure.ac	Fri Mar 11 22:53:15 2016 +0100
+++ b/configure.ac	Sun Mar 13 02:26:06 2016 +0000
@@ -355,17 +355,28 @@
 ##AC_ARG_WITH(dyld,
 ##            AS_HELP_STRING([--with-dyld],
 ##                           [Use (OpenStep|Rhapsody) dynamic linker]))
-##
-# Set name for machine-dependent library files
+
+# Set name for machine-dependent library files.
+# Variables ac_sys_system and ac_sys_release are used for setting
+# a lot of different things including 'define_xopen_source'
+# in a case statement below.
 AC_ARG_VAR([MACHDEP], [name for machine-dependent library files])
 AC_MSG_CHECKING(MACHDEP)
+case "$host" in
+*-*-mingw*)
+    # On those hosts MACHDEP is 'win', as platform-specific files
+    # go in plat-$(MACHDEP), but runtime platform is 'win32'
+    test -z "$MACHDEP" && MACHDEP=win
+
+    dnl Configuration will be based only on "host triplet" as build
+    dnl must not depend from posix-compatible environment.
+    ac_sys_system=ignore
+    ;;
+esac
 if test -z "$MACHDEP"
 then
     # avoid using uname for cross builds
     if test "$cross_compiling" = yes; then
-       # ac_sys_system and ac_sys_release are used for setting
-       # a lot of different things including 'define_xopen_source'
-       # in the case statement below.
 	case "$host" in
 	*-*-linux*)
 		ac_sys_system=Linux
@@ -405,25 +416,34 @@
 
 AC_SUBST(_PYTHON_HOST_PLATFORM)
 if test "$cross_compiling" = yes; then
-	case "$host" in
-	*-*-linux*)
-		case "$host_cpu" in
-		arm*)
-			_host_cpu=arm
+	case "$host_os" in
+	mingw*)
+		# As sys.platform() returns 'win32' to build python and
+		# extensions, we will use 'mingw' (in setup.py etc.)
+		_PYTHON_HOST_PLATFORM=mingw
+		;;
+	*)
+		case "$host" in
+		*-*-linux*)
+			case "$host_cpu" in
+			arm*)
+				_host_cpu=arm
+				;;
+			*)
+				_host_cpu=$host_cpu
+			esac
+			;;
+		*-*-cygwin* | *-*-mingw*)
+			_host_cpu=
 			;;
 		*)
-			_host_cpu=$host_cpu
+			# for now, limit cross builds to known configurations
+			MACHDEP="unknown"
+			AC_MSG_ERROR([cross build not supported for $host])
 		esac
+		_PYTHON_HOST_PLATFORM="$MACHDEP${_host_cpu:+-$_host_cpu}"
 		;;
-	*-*-cygwin*)
-		_host_cpu=
-		;;
-	*)
-		# for now, limit cross builds to known configurations
-		MACHDEP="unknown"
-		AC_MSG_ERROR([cross build not supported for $host])
 	esac
-	_PYTHON_HOST_PLATFORM="$MACHDEP${_host_cpu:+-$_host_cpu}"
 fi
 
 # Some systems cannot stand _XOPEN_SOURCE being defined at all; they