diff -Naur Python-3.6.5-orig/configure.ac Python-3.6.5/configure.ac
--- Python-3.6.5-orig/configure.ac	2018-04-16 09:53:08.790604200 +0300
+++ Python-3.6.5/configure.ac	2018-04-16 09:53:09.021005200 +0300
@@ -5447,6 +5447,16 @@
   THREADHEADERS="$THREADHEADERS \$(srcdir)/$h"
 done
 
+case $host in
+  *-*-mingw*)
+    dnl Required for windows builds as Objects/exceptions.c require
+    dnl "errmap.h" from $srcdir/PC.
+    dnl Note we cannot use BASECPPFLAGS as autogenerated pyconfig.h
+    dnl has to be before customized located in ../PC.
+    CPPFLAGS="-I\$(srcdir)/PC $CPPFLAGS"
+    ;;
+esac
+
 AC_SUBST(SRCDIRS)
 SRCDIRS="Parser Objects Python Modules Programs"
 AC_MSG_CHECKING(for build directories)