diff -r cf91a929b81a .gitignore
--- a/.gitignore	Fri Sep 09 10:36:01 2016 -0700
+++ b/.gitignore	Fri Sep 09 10:51:14 2016 -0700
@@ -22,7 +22,6 @@
 Lib/lib2to3/*.pickle
 Lib/test/data/*
 Lib/_sysconfigdata.py
-Lib/plat-mac/errors.rsrc.df.rsrc
 Makefile
 Makefile.pre
 Misc/python.pc
diff -r cf91a929b81a .hgignore
--- a/.hgignore	Fri Sep 09 10:36:01 2016 -0700
+++ b/.hgignore	Fri Sep 09 10:51:14 2016 -0700
@@ -26,7 +26,6 @@
 python-config.py$
 reflog.txt$
 tags$
-Lib/plat-mac/errors.rsrc.df.rsrc
 Misc/python.pc
 Misc/python-config.sh$
 Modules/Setup$
diff -r cf91a929b81a Lib/sysconfig.py
--- a/Lib/sysconfig.py	Fri Sep 09 10:36:01 2016 -0700
+++ b/Lib/sysconfig.py	Fri Sep 09 10:51:14 2016 -0700
@@ -341,6 +341,15 @@
         config_dir_name += '-%s' % sys.implementation._multiarch
     return os.path.join(get_path('stdlib'), config_dir_name, 'Makefile')
 
+
+def _get_sysconfigdata_name():
+    return '_sysconfigdata_{abi}_{platform}_{multiarch}'.format(
+        abi=sys.abiflags,
+        platform=sys.platform,
+        multiarch=getattr(sys.implementation, '_multiarch', ''),
+    )
+
+
 def _generate_posix_vars():
     """Generate the Python module containing build-time variables."""
     import pprint
@@ -381,7 +390,7 @@
     # _sysconfigdata module manually and populate it with the build vars.
     # This is more than sufficient for ensuring the subsequent call to
     # get_platform() succeeds.
-    name = '_sysconfigdata_' + sys.abiflags
+    name = _get_sysconfigdata_name()
     if 'darwin' in sys.platform:
         import types
         module = types.ModuleType(name)
@@ -407,7 +416,7 @@
 def _init_posix(vars):
     """Initialize the module as appropriate for POSIX systems."""
     # _sysconfigdata is generated at build time, see _generate_posix_vars()
-    name = '_sysconfigdata_' + sys.abiflags
+    name = _get_sysconfigdata_name()
     _temp = __import__(name, globals(), locals(), ['build_time_vars'], 0)
     build_time_vars = _temp.build_time_vars
     vars.update(build_time_vars)
diff -r cf91a929b81a Mac/BuildScript/build-installer.py
--- a/Mac/BuildScript/build-installer.py	Fri Sep 09 10:36:01 2016 -0700
+++ b/Mac/BuildScript/build-installer.py	Fri Sep 09 10:51:14 2016 -0700
@@ -1292,7 +1292,8 @@
 
     import pprint
     if getVersionMajorMinor() >= (3, 6):
-        path = os.path.join(path_to_lib, 'plat-darwin', '_sysconfigdata_m.py')
+        # XXX this is extra-fragile
+        path = os.path.join(path_to_lib, '_sysconfigdata_m_darwin_darwin.py')
     else:
         path = os.path.join(path_to_lib, '_sysconfigdata.py')
     fp = open(path, 'r')
diff -r cf91a929b81a Makefile.pre.in
--- a/Makefile.pre.in	Fri Sep 09 10:36:01 2016 -0700
+++ b/Makefile.pre.in	Fri Sep 09 10:51:14 2016 -0700
@@ -1155,8 +1155,6 @@
 	(cd $(DESTDIR)$(MANDIR)/man1; $(LN) -s python$(VERSION).1 python3.1)
 
 # Install the library
-PLATDIR=	@PLATDIR@
-MACHDEPS=	$(PLATDIR)
 XMLLIBSUBDIRS=  xml xml/dom xml/etree xml/parsers xml/sax
 LIBSUBDIRS=	tkinter tkinter/test tkinter/test/test_tkinter \
 		tkinter/test/test_ttk site-packages test \
@@ -1214,8 +1212,8 @@
 		multiprocessing multiprocessing/dummy \
 		unittest unittest/test unittest/test/testmock \
 		venv venv/scripts venv/scripts/posix \
-		curses pydoc_data $(MACHDEPS)
-libinstall:	build_all $(srcdir)/Lib/$(PLATDIR) $(srcdir)/Modules/xxmodule.c
+		curses pydoc_data
+libinstall:	build_all $(srcdir)/Modules/xxmodule.c
 	@for i in $(SCRIPTDIR) $(LIBDEST); \
 	do \
 		if test ! -d $(DESTDIR)$$i; then \
@@ -1270,10 +1268,10 @@
 			esac; \
 		done; \
 	done
-	$(INSTALL_DATA) `cat pybuilddir.txt`/_sysconfigdata_$(ABIFLAGS).py \
-		$(DESTDIR)$(LIBDEST)/$(PLATDIR); \
+	$(INSTALL_DATA) `cat pybuilddir.txt`/_sysconfigdata_$(ABIFLAGS)_$(MACHDEP)_$(MULTIARCH).py \
+		$(DESTDIR)$(LIBDEST); \
 	echo $(INSTALL_DATA) `cat pybuilddir.txt`/_sysconfigdata_$(ABIFLAGS).py \
-		$(LIBDEST)/$(PLATDIR)
+		$(LIBDEST)
 	$(INSTALL_DATA) $(srcdir)/LICENSE $(DESTDIR)$(LIBDEST)/LICENSE.txt
 	if test -d $(DESTDIR)$(LIBDEST)/distutils/tests; then \
 		$(INSTALL_DATA) $(srcdir)/Modules/xxmodule.c \
@@ -1311,9 +1309,6 @@
 	-PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
 		$(PYTHON_FOR_BUILD) -m lib2to3.pgen2.driver $(DESTDIR)$(LIBDEST)/lib2to3/PatternGrammar.txt
 
-$(srcdir)/Lib/$(PLATDIR):
-	mkdir $(srcdir)/Lib/$(PLATDIR)
-
 python-config: $(srcdir)/Misc/python-config.in Misc/python-config.sh
 	# Substitution happens here, as the completely-expanded BINDIR
 	# is not available in configure
@@ -1589,9 +1584,6 @@
 	-rm -rf build platform
 	-rm -rf $(PYTHONFRAMEWORKDIR)
 	-rm -f python-config.py python-config
-	if [ -n "$(MULTIARCH)" ]; then \
-	  rm -rf $(srcdir)/Lib/$(PLATDIR); \
-	fi
 
 # Make things extra clean, before making a distribution:
 # remove all generated files, even Makefile[.pre]
diff -r cf91a929b81a PC/getpathp.c
--- a/PC/getpathp.c	Fri Sep 09 10:36:01 2016 -0700
+++ b/PC/getpathp.c	Fri Sep 09 10:51:14 2016 -0700
@@ -25,8 +25,8 @@
    * We attempt to locate the "Python Home" - if the PYTHONHOME env var
      is set, we believe it.  Otherwise, we use the path of our host .EXE's
      to try and locate our "landmark" (lib\\os.py) and deduce our home.
-     - If we DO have a Python Home: The relevant sub-directories (Lib,
-       plat-win, etc) are based on the Python Home
+     - If we DO have a Python Home: The relevant sub-directories (Lib) are
+       based on the Python Home
      - If we DO NOT have a Python Home, the core Python Path is
        loaded from the registry.  This is the main PythonPath key,
        and both HKLM and HKCU are combined to form the path)
@@ -34,7 +34,7 @@
    * Iff - we can not locate the Python Home, have not had a PYTHONPATH
      specified, and can't locate any Registry entries (ie, we have _nothing_
      we can assume is a good path), a default path with relative entries is
-     used (eg. .\Lib;.\plat-win, etc)
+     used (eg. .\Lib;.\DLLs, etc)
 
 
    If a sys.path file exists adjacent to python.exe, it must contain a
diff -r cf91a929b81a Tools/msi/make_zip.py
--- a/Tools/msi/make_zip.py	Fri Sep 09 10:36:01 2016 -0700
+++ b/Tools/msi/make_zip.py	Fri Sep 09 10:51:14 2016 -0700
@@ -67,8 +67,6 @@
     if p.is_dir():
         if name in EXCLUDE_FROM_LIBRARY:
             return False
-        if name.startswith('plat-'):
-            return False
         if name == 'test' and p.parts[-2].lower() == 'lib':
             return False
         if name in {'test', 'tests'} and p.parts[-3].lower() == 'lib':
diff -r cf91a929b81a configure
--- a/configure	Fri Sep 09 10:36:01 2016 -0700
+++ b/configure	Fri Sep 09 10:51:14 2016 -0700
@@ -710,7 +710,6 @@
 NO_AS_NEEDED
 MULTIARCH_CPPFLAGS
 PLATFORM_TRIPLET
-PLATDIR
 MULTIARCH
 ac_ct_CXX
 MAINCC
@@ -782,7 +781,6 @@
 docdir
 oldincludedir
 includedir
-runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -894,7 +892,6 @@
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
-runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1147,15 +1144,6 @@
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
-  -runstatedir | --runstatedir | --runstatedi | --runstated \
-  | --runstate | --runstat | --runsta | --runst | --runs \
-  | --run | --ru | --r)
-    ac_prev=runstatedir ;;
-  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
-  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
-  | --run=* | --ru=* | --r=*)
-    runstatedir=$ac_optarg ;;
-
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1293,7 +1281,7 @@
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir runstatedir
+		libdir localedir mandir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1446,7 +1434,6 @@
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
-  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -2940,7 +2927,7 @@
 	fi
         { $as_echo "$as_me:${as_lineno-$LINENO}: result: $interp" >&5
 $as_echo "$interp" >&6; }
-	PYTHON_FOR_BUILD='_PYTHON_PROJECT_BASE=$(abs_builddir) _PYTHON_HOST_PLATFORM=$(_PYTHON_HOST_PLATFORM) PYTHONPATH=$(shell test -f pybuilddir.txt && echo $(abs_builddir)/`cat pybuilddir.txt`:)$(srcdir)/Lib:$(srcdir)/Lib/$(PLATDIR) '$interp
+	PYTHON_FOR_BUILD='_PYTHON_PROJECT_BASE=$(abs_builddir) _PYTHON_HOST_PLATFORM=$(_PYTHON_HOST_PLATFORM) PYTHONPATH=$(shell test -f pybuilddir.txt && echo $(abs_builddir)/`cat pybuilddir.txt`:)$(srcdir)/Lib '$interp
     fi
     # Used to comment out stuff for rebuilding generated files
     GENERATED_COMMENT='#'
@@ -5303,12 +5290,6 @@
 elif test x$PLATFORM_TRIPLET != x && test x$MULTIARCH = x; then
   MULTIARCH=$PLATFORM_TRIPLET
 fi
-if test x$PLATFORM_TRIPLET = x; then
-  PLATDIR=plat-$MACHDEP
-else
-  PLATDIR=plat-$PLATFORM_TRIPLET
-fi
-
 
 if test x$MULTIARCH != x; then
   MULTIARCH_CPPFLAGS="-DMULTIARCH=\\\"$MULTIARCH\\\""
diff -r cf91a929b81a configure.ac
--- a/configure.ac	Fri Sep 09 10:36:01 2016 -0700
+++ b/configure.ac	Fri Sep 09 10:51:14 2016 -0700
@@ -78,7 +78,7 @@
 	    AC_MSG_ERROR([python$PACKAGE_VERSION interpreter not found])
 	fi
         AC_MSG_RESULT($interp)
-	PYTHON_FOR_BUILD='_PYTHON_PROJECT_BASE=$(abs_builddir) _PYTHON_HOST_PLATFORM=$(_PYTHON_HOST_PLATFORM) PYTHONPATH=$(shell test -f pybuilddir.txt && echo $(abs_builddir)/`cat pybuilddir.txt`:)$(srcdir)/Lib:$(srcdir)/Lib/$(PLATDIR) '$interp
+	PYTHON_FOR_BUILD='_PYTHON_PROJECT_BASE=$(abs_builddir) _PYTHON_HOST_PLATFORM=$(_PYTHON_HOST_PLATFORM) PYTHONPATH=$(shell test -f pybuilddir.txt && echo $(abs_builddir)/`cat pybuilddir.txt`:)$(srcdir)/Lib '$interp
     fi
     # Used to comment out stuff for rebuilding generated files
     GENERATED_COMMENT='#'
@@ -909,12 +909,6 @@
 elif test x$PLATFORM_TRIPLET != x && test x$MULTIARCH = x; then
   MULTIARCH=$PLATFORM_TRIPLET
 fi
-if test x$PLATFORM_TRIPLET = x; then
-  PLATDIR=plat-$MACHDEP
-else
-  PLATDIR=plat-$PLATFORM_TRIPLET
-fi
-AC_SUBST(PLATDIR)
 AC_SUBST(PLATFORM_TRIPLET)
 if test x$MULTIARCH != x; then
   MULTIARCH_CPPFLAGS="-DMULTIARCH=\\\"$MULTIARCH\\\""