@@ -822,6 +822,7 @@ regen-grammar: regen-token
 
 .PHONY: regen-pegen
 regen-pegen:
+	@$(MKDIR_P) -p $(srcdir)/Parser/pegen
 	PYTHONPATH=$(srcdir)/Tools/peg_generator $(PYTHON_FOR_REGEN) -m pegen -c -q $(srcdir)/Grammar/python.gram \
 		-o $(srcdir)/Parser/pegen/parse.new.c
 	$(UPDATE_FILE) $(srcdir)/Parser/pegen/parse.c $(srcdir)/Parser/pegen/parse.new.c
 
@@ -1,6 +1,6 @@
-# generated automatically by aclocal 1.15 -*- Autoconf -*-
+# generated automatically by aclocal 1.16.2 -*- Autoconf -*-
 
-# Copyright (C) 1996-2014 Free Software Foundation, Inc.
+# Copyright (C) 1996-2020 Free Software Foundation, Inc.
 
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -12,9 +12,9 @@
 # PARTICULAR PURPOSE.
 
 m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
-dnl pkg.m4 - Macros to locate and utilise pkg-config.   -*- Autoconf -*-
-dnl serial 11 (pkg-config-0.29.1)
-dnl
+# pkg.m4 - Macros to locate and utilise pkg-config.   -*- Autoconf -*-
+# serial 11 (pkg-config-0.29.1)
+
 dnl Copyright © 2004 Scott James Remnant <scott@netsplit.com>.
 dnl Copyright © 2012-2015 Dan Nicholson <dbn.lists@gmail.com>
 dnl
@@ -288,5 +288,73 @@ AS_VAR_COPY([$1], [pkg_cv_][$1])
 AS_VAR_IF([$1], [""], [$5], [$4])dnl
 ])dnl PKG_CHECK_VAR
 
+dnl PKG_WITH_MODULES(VARIABLE-PREFIX, MODULES,
+dnl   [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND],
+dnl   [DESCRIPTION], [DEFAULT])
+dnl ------------------------------------------
+dnl
+dnl Prepare a "--with-" configure option using the lowercase
+dnl [VARIABLE-PREFIX] name, merging the behaviour of AC_ARG_WITH and
+dnl PKG_CHECK_MODULES in a single macro.
+AC_DEFUN([PKG_WITH_MODULES],
+[
+m4_pushdef([with_arg], m4_tolower([$1]))
+
+m4_pushdef([description],
+           [m4_default([$5], [build with ]with_arg[ support])])
+
+m4_pushdef([def_arg], [m4_default([$6], [auto])])
+m4_pushdef([def_action_if_found], [AS_TR_SH([with_]with_arg)=yes])
+m4_pushdef([def_action_if_not_found], [AS_TR_SH([with_]with_arg)=no])
+
+m4_case(def_arg,
+            [yes],[m4_pushdef([with_without], [--without-]with_arg)],
+            [m4_pushdef([with_without],[--with-]with_arg)])
+
+AC_ARG_WITH(with_arg,
+     AS_HELP_STRING(with_without, description[ @<:@default=]def_arg[@:>@]),,
+    [AS_TR_SH([with_]with_arg)=def_arg])
+
+AS_CASE([$AS_TR_SH([with_]with_arg)],
+            [yes],[PKG_CHECK_MODULES([$1],[$2],$3,$4)],
+            [auto],[PKG_CHECK_MODULES([$1],[$2],
+                                        [m4_n([def_action_if_found]) $3],
+                                        [m4_n([def_action_if_not_found]) $4])])
+
+m4_popdef([with_arg])
+m4_popdef([description])
+m4_popdef([def_arg])
+
+])dnl PKG_WITH_MODULES
+
+dnl PKG_HAVE_WITH_MODULES(VARIABLE-PREFIX, MODULES,
+dnl   [DESCRIPTION], [DEFAULT])
+dnl -----------------------------------------------
+dnl
+dnl Convenience macro to trigger AM_CONDITIONAL after PKG_WITH_MODULES
+dnl check._[VARIABLE-PREFIX] is exported as make variable.
+AC_DEFUN([PKG_HAVE_WITH_MODULES],
+[
+PKG_WITH_MODULES([$1],[$2],,,[$3],[$4])
+
+AM_CONDITIONAL([HAVE_][$1],
+               [test "$AS_TR_SH([with_]m4_tolower([$1]))" = "yes"])
+])dnl PKG_HAVE_WITH_MODULES
+
+dnl PKG_HAVE_DEFINE_WITH_MODULES(VARIABLE-PREFIX, MODULES,
+dnl   [DESCRIPTION], [DEFAULT])
+dnl ------------------------------------------------------
+dnl
+dnl Convenience macro to run AM_CONDITIONAL and AC_DEFINE after
+dnl PKG_WITH_MODULES check. HAVE_[VARIABLE-PREFIX] is exported as make
+dnl and preprocessor variable.
+AC_DEFUN([PKG_HAVE_DEFINE_WITH_MODULES],
+[
+PKG_HAVE_WITH_MODULES([$1],[$2],[$3],[$4])
+
+AS_IF([test "$AS_TR_SH([with_]m4_tolower([$1]))" = "yes"],
+        [AC_DEFINE([HAVE_][$1], 1, [Enable ]m4_tolower([$1])[ support])])
+])dnl PKG_HAVE_DEFINE_WITH_MODULES
+
 m4_include([m4/ax_c_float_words_bigendian.m4])
 m4_include([m4/ax_check_openssl.m4])
@@ -16746,7 +16746,7 @@ do
 done
 
 
-SRCDIRS="Parser Objects Python Modules Modules/_io Programs"
+SRCDIRS="Parser Parser/pegen Objects Python Modules Modules/_io Programs"
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for build directories" >&5
 $as_echo_n "checking for build directories... " >&6; }
 for dir in $SRCDIRS; do
 
@@ -5397,7 +5397,7 @@ do
 done
 
 AC_SUBST(SRCDIRS)
-SRCDIRS="Parser Objects Python Modules Modules/_io Programs"
+SRCDIRS="Parser Parser/pegen Objects Python Modules Modules/_io Programs"
 AC_MSG_CHECKING(for build directories)
 for dir in $SRCDIRS; do
     if test ! -d $dir; then