perl-5.16.2/make_ext.pl - toolchain/perl - Git at Google

 #!./miniperl
 use strict;
 use warnings;
 use Config;
 BEGIN {
     if ($^O eq 'MSWin32') {
 	unshift @INC, '../dist/Cwd';
 	require FindExt;
     } else {
 	unshift @INC, 'dist/Cwd';
     }
 }
 use Cwd;

 my $is_Win32 = $^O eq 'MSWin32';
 my $is_VMS = $^O eq 'VMS';
 my $is_Unix = !$is_Win32 && !$is_VMS;

 my @ext_dirs = qw(cpan dist ext);
 my $ext_dirs_re = '(?:' . join('|', @ext_dirs) . ')';

 # This script acts as a simple interface for building extensions.

 # It's actually a cut and shut of the Unix version ext/utils/makeext and the
 # Windows version win32/build_ext.pl hence the two invocation styles.

 # On Unix, it primarily used by the perl Makefile one extension at a time:
 #
 # d_dummy $(dynamic_ext): miniperl preplibrary FORCE
 # 	@$(RUN) ./miniperl make_ext.pl --target=dynamic $@ MAKE=$(MAKE) LIBPERL_A=$(LIBPERL)
 #
 # On Windows or VMS,
 # If '--static' is specified, static extensions will be built.
 # If '--dynamic' is specified, dynamic extensions will be built.
 # If '--nonxs' is specified, nonxs extensions will be built.
 # If '--dynaloader' is specified, DynaLoader will be built.
 # If '--all' is specified, all extensions will be built.
 #
 #    make_ext.pl "MAKE=make [-make_opts]" --dir=directory [--target=target] [--static|--dynamic|--all] +ext2 !ext1
 #
 # E.g.
 #
 #     make_ext.pl "MAKE=nmake -nologo" --dir=..\ext
 #
 #     make_ext.pl "MAKE=nmake -nologo" --dir=..\ext --target=clean
 #
 #     make_ext.pl MAKE=dmake --dir=..\ext
 #
 #     make_ext.pl MAKE=dmake --dir=..\ext --target=clean
 #
 # Will skip building extensions which are marked with an '!' char.
 # Mostly because they still not ported to specified platform.
 #
 # If any extensions are listed with a '+' char then only those
 # extensions will be built, but only if they arent countermanded
 # by an '!ext' and are appropriate to the type of building being done.

 # It may be deleted in a later release of perl so try to
 # avoid using it for other purposes.

 my (%excl, %incl, %opts, @extspec, @pass_through);

 foreach (@ARGV) {
     if (/^!(.*)$/) {
 	$excl{$1} = 1;
     } elsif (/^\+(.*)$/) {
 	$incl{$1} = 1;
     } elsif (/^--([\w\-]+)$/) {
 	$opts{$1} = 1;
     } elsif (/^--([\w\-]+)=(.*)$/) {
 	push @{$opts{$1}}, $2;
     } elsif (/=/) {
 	push @pass_through, $_;
     } elsif (length) {
 	push @extspec, $_;
     }
 }

 my $static = $opts{static} || $opts{all};
 my $dynamic = $opts{dynamic} || $opts{all};
 my $nonxs = $opts{nonxs} || $opts{all};
 my $dynaloader = $opts{dynaloader} || $opts{all};

 # The Perl Makefile.SH will expand all extensions to
 #	lib/auto/X/X.a  (or lib/auto/X/Y/Y.a if nested)
 # A user wishing to run make_ext might use
 #	X (or X/Y or X::Y if nested)

 # canonise into X/Y form (pname)

 foreach (@extspec) {
     if (s{^lib/auto/}{}) {
 	# Remove lib/auto prefix and /*.* suffix
 	s{/[^/]+\.[^/]+$}{};
     } elsif (s{^$ext_dirs_re/}{}) {
 	# Remove ext/ prefix and /pm_to_blib suffix
 	s{/pm_to_blib$}{};
 	# Targets are given as files on disk, but the extension spec is still
 	# written using /s for each ::
 	tr!-!/!;
     } elsif (s{::}{\/}g) {
 	# Convert :: to /
     } else {
 	s/\..*o//;
     }
 }

 my $makecmd  = shift @pass_through; # Should be something like MAKE=make
 unshift @pass_through, 'PERL_CORE=1';

 my @dirs  = @{$opts{dir} || \@ext_dirs};
 my $target   = $opts{target}[0];
 $target = 'all' unless defined $target;

 # Previously, $make was taken from config.sh.  However, the user might
 # instead be running a possibly incompatible make.  This might happen if
 # the user types "gmake" instead of a plain "make", for example.  The
 # correct current value of MAKE will come through from the main perl
 # makefile as MAKE=/whatever/make in $makecmd.  We'll be cautious in
 # case third party users of this script (are there any?) don't have the
 # MAKE=$(MAKE) argument, which was added after 5.004_03.
 unless(defined $makecmd and $makecmd =~ /^MAKE=(.*)$/) {
     die "$0:  WARNING:  Please include MAKE=\$(MAKE) in \@ARGV\n";
 }

 # This isn't going to cope with anything fancy, such as spaces inside command
 # names, but neither did what it replaced. Once there is a use case that needs
 # it, please supply patches. Until then, I'm sticking to KISS
 my @make = split ' ', $1 || $Config{make} || $ENV{MAKE};
 # Using an array of 0 or 1 elements makes the subsequent code simpler.
 my @run = $Config{run};
 @run = () if not defined $run[0] or $run[0] eq '';


 if ($target eq '') {
     die "make_ext: no make target specified (eg all or clean)\n";
 } elsif ($target !~ /(?:^all|clean)$/) {
     # for the time being we are strict about what make_ext is used for
     die "$0: unknown make target '$target'\n";
 }

 if (!@extspec and !$static and !$dynamic and !$nonxs and !$dynaloader)  {
     die "$0: no extension specified\n";
 }

 my $perl;
 my %extra_passthrough;

 if ($is_Win32) {
     my $build = getcwd();
     $perl = $^X;
     if ($perl =~ m#^\.\.#) {
 	my $here = $build;
 	$here =~ s{/}{\\}g;
 	$perl = "$here\\$perl";
     }
     (my $topdir = $perl) =~ s/\\[^\\]+$//;
     # miniperl needs to find perlglob and pl2bat
     $ENV{PATH} = "$topdir;$topdir\\win32\\bin;$ENV{PATH}";
     my $pl2bat = "$topdir\\win32\\bin\\pl2bat";
     unless (-f "$pl2bat.bat") {
 	my @args = ($perl, "-I$topdir\\lib", ("$pl2bat.pl") x 2);
 	print "@args\n";
 	system(@args) unless defined $::Cross::platform;
     }

     print "In $build";
     foreach my $dir (@dirs) {
 	chdir($dir) or die "Cannot cd to $dir: $!\n";
 	(my $ext = getcwd()) =~ s{/}{\\}g;
 	FindExt::scan_ext($ext);
 	FindExt::set_static_extensions(split ' ', $Config{static_ext});
 	chdir $build
 	    or die "Couldn't chdir to '$build': $!"; # restore our start directory
     }

     my @ext;
     push @ext, FindExt::static_ext() if $static;
     push @ext, FindExt::dynamic_ext() if $dynamic;
     push @ext, FindExt::nonxs_ext() if $nonxs;
     push @ext, 'DynaLoader' if $dynaloader;

     foreach (sort @ext) {
 	if (%incl and !exists $incl{$_}) {
 	    #warn "Skipping extension $_, not in inclusion list\n";
 	    next;
 	}
 	if (exists $excl{$_}) {
 	    warn "Skipping extension $_, not ported to current platform";
 	    next;
 	}
 	push @extspec, $_;
 	if($_ eq 'DynaLoader' and $target !~ /clean$/) {
 	    # No, we don't know why nmake can't work out the dependency chain
 	    push @{$extra_passthrough{$_}}, 'DynaLoader.c';
 	} elsif(FindExt::is_static($_)) {
 	    push @{$extra_passthrough{$_}}, 'LINKTYPE=static';
 	}
     }

     chdir '..'
 	or die "Couldn't chdir to build directory: $!"; # now in the Perl build
 }
 elsif ($is_VMS) {
     $perl = $^X;
     push @extspec, (split ' ', $Config{static_ext}) if $static;
     push @extspec, (split ' ', $Config{dynamic_ext}) if $dynamic;
     push @extspec, (split ' ', $Config{nonxs_ext}) if $nonxs;
     push @extspec, 'DynaLoader' if $dynaloader;
 }

 {
     # Cwd needs to be built before Encode recurses into subdirectories.
     # Pod::Simple needs to be built before Pod::Functions
     # This seems to be the simplest way to ensure this ordering:
     my (@first, @other);
     foreach (@extspec) {
 	if ($_ eq 'Cwd' || $_ eq 'Pod/Simple') {
 	    push @first, $_;
 	} else {
 	    push @other, $_;
 	}
     }
     @extspec = (@first, @other);
 }

 if ($Config{osname} eq 'catamount' and @extspec) {
     # Snowball's chance of building extensions.
     die "This is $Config{osname}, not building $extspec[0], sorry.\n";
 }

 foreach my $spec (@extspec)  {
     my $mname = $spec;
     $mname =~ s!/!::!g;
     my $ext_pathname;

     # Try new style ext/Data-Dumper/ first
     my $copy = $spec;
     $copy =~ tr!/!-!;
     foreach my $dir (@ext_dirs) {
 	if (-d "$dir/$copy") {
 	    $ext_pathname = "$dir/$copy";
 	    last;
 	}
     }

     if (!defined $ext_pathname) {
 	if (-d "ext/$spec") {
 	    # Old style ext/Data/Dumper/
 	    $ext_pathname = "ext/$spec";
 	} else {
 	    warn "Can't find extension $spec in any of @ext_dirs";
 	    next;
 	}
     }

     print "\tMaking $mname ($target)\n";

     build_extension($ext_pathname, $perl, $mname,
 		    [@pass_through, @{$extra_passthrough{$spec} || []}]);
 }

 sub build_extension {
     my ($ext_dir, $perl, $mname, $pass_through) = @_;

     unless (chdir "$ext_dir") {
 	warn "Cannot cd to $ext_dir: $!";
 	return;
     }

     my $up = $ext_dir;
     $up =~ s![^/]+!..!g;

     $perl ||= "$up/miniperl";
     my $return_dir = $up;
     my $lib_dir = "$up/lib";
     $ENV{PERL_CORE} = 1;

     my $makefile;
     if ($is_VMS) {
 	$makefile = 'descrip.mms';
 	if ($target =~ /clean$/
 	    && !-f $makefile
 	    && -f "${makefile}_old") {
 	    $makefile = "${makefile}_old";
 	}
     } else {
 	$makefile = 'Makefile';
     }

     if (!-f $makefile) {
 	if (!-f 'Makefile.PL') {
 	    print "\nCreating Makefile.PL in $ext_dir for $mname\n";
 	    my ($fromname, $key, $value);
 	    if ($mname eq 'podlators') {
 		# We need to special case this somewhere, and this is fewer
 		# lines of code than a core-only Makefile.PL, and no more
 		# complex
 		$fromname = 'VERSION';
 		$key = 'DISTNAME';
 		$value = 'podlators';
 		$mname = 'Pod';
 	    } else {
 		$key = 'ABSTRACT_FROM';
 		# We need to cope well with various possible layouts
 		my @dirs = split /::/, $mname;
 		my $leaf = pop @dirs;
 		my $leafname = "$leaf.pm";
 		my $pathname = join '/', @dirs, $leafname;
 		my @locations = ($leafname, $pathname, "lib/$pathname");
 		foreach (@locations) {
 		    if (-f $_) {
 			$fromname = $_;
 			last;
 		    }
 		}

 		unless ($fromname) {
 		    die "For $mname tried @locations in in $ext_dir but can't find source";
 		}
 		($value = $fromname) =~ s/\.pm\z/.pod/;
 		$value = $fromname unless -e $value;
 	    }
 	    open my $fh, '>', 'Makefile.PL'
 		or die "Can't open Makefile.PL for writing: $!";
 	    printf $fh <<'EOM', $0, $mname, $fromname, $key, $value;
 #-*- buffer-read-only: t -*-

 # This Makefile.PL was written by %s.
 # It will be deleted automatically by make realclean

 use strict;
 use ExtUtils::MakeMaker;

 # This is what the .PL extracts to. Not the ultimate file that is installed.
 # (ie Win32 runs pl2bat after this)

 # Doing this here avoids all sort of quoting issues that would come from
 # attempting to write out perl source with literals to generate the arrays and
 # hash.
 my @temps = 'Makefile.PL';
 foreach (glob('scripts/pod*.PL')) {
     # The various pod*.PL extractors change directory. Doing that with relative
     # paths in @INC breaks. It seems the lesser of two evils to copy (to avoid)
     # the chdir doing anything, than to attempt to convert lib paths to
     # absolute, and potentially run into problems with quoting special
     # characters in the path to our build dir (such as spaces)
     require File::Copy;

     my $temp = $_;
     $temp =~ s!scripts/!!;
     File::Copy::copy($_, $temp) or die "Can't copy $temp to $_: $!";
     push @temps, $temp;
 }

 my $script_ext = $^O eq 'VMS' ? '.com' : '';
 my %%pod_scripts;
 foreach (glob('pod*.PL')) {
     my $script = $_;
     s/.PL$/$script_ext/i;
     $pod_scripts{$script} = $_;
 }
 my @exe_files = values %%pod_scripts;

 WriteMakefile(
     NAME          => '%s',
     VERSION_FROM  => '%s',
     %-13s => '%s',
     realclean     => { FILES => "@temps" },
     (%%pod_scripts ? (
         PL_FILES  => \%%pod_scripts,
         EXE_FILES => \@exe_files,
         clean     => { FILES => "@exe_files" },
     ) : ()),
 );

 # ex: set ro:
 EOM
 	    close $fh or die "Can't close Makefile.PL: $!";
 	}
   eval {
     my $ftime = time - 4;
     utime $ftime, $ftime, 'Makefile.PL';
   };
 	print "\nRunning Makefile.PL in $ext_dir\n";

 	# Presumably this can be simplified
 	my @cross;
 	if (defined $::Cross::platform) {
 	    # Inherited from win32/buildext.pl
 	    @cross = "-MCross=$::Cross::platform";
 	} elsif ($opts{cross}) {
 	    # Inherited from make_ext.pl
 	    @cross = '-MCross';
 	}

 	my @args = ("-I$lib_dir", @cross, 'Makefile.PL');
 	if ($is_VMS) {
 	    my $libd = VMS::Filespec::vmspath($lib_dir);
 	    push @args, "INST_LIB=$libd", "INST_ARCHLIB=$libd";
 	} else {
 	    push @args, 'INSTALLDIRS=perl', 'INSTALLMAN1DIR=none',
 		'INSTALLMAN3DIR=none';
 	}
 	push @args, @$pass_through;
 	_quote_args(\@args) if $is_VMS;
 	print join(' ', @run, $perl, @args), "\n";
 	my $code = system @run, $perl, @args;
 	warn "$code from $ext_dir\'s Makefile.PL" if $code;

 	# Right. The reason for this little hack is that we're sitting inside
 	# a program run by ./miniperl, but there are tasks we need to perform
 	# when the 'realclean', 'distclean' or 'veryclean' targets are run.
 	# Unfortunately, they can be run *after* 'clean', which deletes
 	# ./miniperl
 	# So we do our best to leave a set of instructions identical to what
 	# we would do if we are run directly as 'realclean' etc
 	# Whilst we're perfect, unfortunately the targets we call are not, as
 	# some of them rely on a $(PERL) for their own distclean targets.
 	# But this always used to be a problem with the old /bin/sh version of
 	# this.
 	if ($is_Unix) {
 	    my $suffix = '.sh';
 	    foreach my $clean_target ('realclean', 'veryclean') {
 		my $file = "$return_dir/$clean_target$suffix";
 		open my $fh, '>>', $file or die "open $file: $!";
 		# Quite possible that we're being run in parallel here.
 		# Can't use Fcntl this early to get the LOCK_EX
 		flock $fh, 2 or warn "flock $file: $!";
 		print $fh <<"EOS";
 cd $ext_dir
 if test ! -f Makefile -a -f Makefile.old; then
     echo "Note: Using Makefile.old"
     make -f Makefile.old $clean_target MAKE='@make' @pass_through
 else
     if test ! -f Makefile ; then
 	echo "Warning: No Makefile!"
     fi
     make $clean_target MAKE='@make' @pass_through
 fi
 cd $return_dir
 EOS
 		close $fh or die "close $file: $!";
 	    }
 	}
     }

     if (not -f $makefile) {
 	print "Warning: No Makefile!\n";
     }

     if ($is_VMS) {
 	_macroify_passthrough($pass_through);
 	unshift @$pass_through, "/DESCRIPTION=$makefile";
     }

     if (!$target or $target !~ /clean$/) {
 	# Give makefile an opportunity to rewrite itself.
 	# reassure users that life goes on...
 	my @args = ('config', @$pass_through);
 	system(@run, @make, @args) and print "@run @make @args failed, continuing anyway...\n";
     }
     my @targ = ($target, @$pass_through);
     print "Making $target in $ext_dir\n@run @make @targ\n";
     my $code = system(@run, @make, @targ);
     die "Unsuccessful make($ext_dir): code=$code" if $code != 0;

     chdir $return_dir || die "Cannot cd to $return_dir: $!";
 }

 sub _quote_args {
     my $args = shift; # must be array reference

     # Do not quote qualifiers that begin with '/'.
     map { if (!/^\//) {
           $_ =~ s/\"/""/g;     # escape C<"> by doubling
           $_ = q(").$_.q(");
         }
     } @{$args}
     ;
 }

 sub _macroify_passthrough {
     my $passthrough = shift;
     _quote_args($passthrough);
     my $macro = '/MACRO=(' . join(',',@$passthrough) . ')';
     @$passthrough = ();
     @$passthrough[0] = $macro;
 }
	#!./miniperl
	use strict;
	use warnings;
	use Config;
	BEGIN {
	if ($^O eq 'MSWin32') {
	unshift @INC, '../dist/Cwd';
	require FindExt;
	} else {
	unshift @INC, 'dist/Cwd';
	}
	}
	use Cwd;

	my $is_Win32 = $^O eq 'MSWin32';
	my $is_VMS = $^O eq 'VMS';
	my $is_Unix = !$is_Win32 && !$is_VMS;

	my @ext_dirs = qw(cpan dist ext);
	my $ext_dirs_re = '(?:' . join('\|', @ext_dirs) . ')';

	# This script acts as a simple interface for building extensions.

	# It's actually a cut and shut of the Unix version ext/utils/makeext and the
	# Windows version win32/build_ext.pl hence the two invocation styles.

	# On Unix, it primarily used by the perl Makefile one extension at a time:
	#
	# d_dummy $(dynamic_ext): miniperl preplibrary FORCE
	# @$(RUN) ./miniperl make_ext.pl --target=dynamic $@ MAKE=$(MAKE) LIBPERL_A=$(LIBPERL)
	#
	# On Windows or VMS,
	# If '--static' is specified, static extensions will be built.
	# If '--dynamic' is specified, dynamic extensions will be built.
	# If '--nonxs' is specified, nonxs extensions will be built.
	# If '--dynaloader' is specified, DynaLoader will be built.
	# If '--all' is specified, all extensions will be built.
	#
	# make_ext.pl "MAKE=make [-make_opts]" --dir=directory [--target=target] [--static\|--dynamic\|--all] +ext2 !ext1
	#
	# E.g.
	#
	# make_ext.pl "MAKE=nmake -nologo" --dir=..\ext
	#
	# make_ext.pl "MAKE=nmake -nologo" --dir=..\ext --target=clean
	#
	# make_ext.pl MAKE=dmake --dir=..\ext
	#
	# make_ext.pl MAKE=dmake --dir=..\ext --target=clean
	#
	# Will skip building extensions which are marked with an '!' char.
	# Mostly because they still not ported to specified platform.
	#
	# If any extensions are listed with a '+' char then only those
	# extensions will be built, but only if they arent countermanded
	# by an '!ext' and are appropriate to the type of building being done.

	# It may be deleted in a later release of perl so try to
	# avoid using it for other purposes.

	my (%excl, %incl, %opts, @extspec, @pass_through);

	foreach (@ARGV) {
	if (/^!(.*)$/) {
	$excl{$1} = 1;
	} elsif (/^\+(.*)$/) {
	$incl{$1} = 1;
	} elsif (/^--([\w\-]+)$/) {
	$opts{$1} = 1;
	} elsif (/^--([\w\-]+)=(.*)$/) {
	push @{$opts{$1}}, $2;
	} elsif (/=/) {
	push @pass_through, $_;
	} elsif (length) {
	push @extspec, $_;
	}
	}

	my $static = $opts{static} \|\| $opts{all};
	my $dynamic = $opts{dynamic} \|\| $opts{all};
	my $nonxs = $opts{nonxs} \|\| $opts{all};
	my $dynaloader = $opts{dynaloader} \|\| $opts{all};

	# The Perl Makefile.SH will expand all extensions to
	# lib/auto/X/X.a (or lib/auto/X/Y/Y.a if nested)
	# A user wishing to run make_ext might use
	# X (or X/Y or X::Y if nested)

	# canonise into X/Y form (pname)

	foreach (@extspec) {
	if (s{^lib/auto/}{}) {
	# Remove lib/auto prefix and /. suffix
	s{/[^/]+\.[^/]+$}{};
	} elsif (s{^$ext_dirs_re/}{}) {
	# Remove ext/ prefix and /pm_to_blib suffix
	s{/pm_to_blib$}{};
	# Targets are given as files on disk, but the extension spec is still
	# written using /s for each ::
	tr!-!/!;
	} elsif (s{::}{\/}g) {
	# Convert :: to /
	} else {
	s/\..*o//;
	}
	}

	my $makecmd = shift @pass_through; # Should be something like MAKE=make
	unshift @pass_through, 'PERL_CORE=1';

	my @dirs = @{$opts{dir} \|\| \@ext_dirs};
	my $target = $opts{target}[0];
	$target = 'all' unless defined $target;

	# Previously, $make was taken from config.sh. However, the user might
	# instead be running a possibly incompatible make. This might happen if
	# the user types "gmake" instead of a plain "make", for example. The
	# correct current value of MAKE will come through from the main perl
	# makefile as MAKE=/whatever/make in $makecmd. We'll be cautious in
	# case third party users of this script (are there any?) don't have the
	# MAKE=$(MAKE) argument, which was added after 5.004_03.
	unless(defined $makecmd and $makecmd =~ /^MAKE=(.*)$/) {
	die "$0: WARNING: Please include MAKE=\$(MAKE) in \@ARGV\n";
	}

	# This isn't going to cope with anything fancy, such as spaces inside command
	# names, but neither did what it replaced. Once there is a use case that needs
	# it, please supply patches. Until then, I'm sticking to KISS
	my @make = split ' ', $1 \|\| $Config{make} \|\| $ENV{MAKE};
	# Using an array of 0 or 1 elements makes the subsequent code simpler.
	my @run = $Config{run};
	@run = () if not defined $run[0] or $run[0] eq '';


	if ($target eq '') {
	die "make_ext: no make target specified (eg all or clean)\n";
	} elsif ($target !~ /(?:^all\|clean)$/) {
	# for the time being we are strict about what make_ext is used for
	die "$0: unknown make target '$target'\n";
	}

	if (!@extspec and !$static and !$dynamic and !$nonxs and !$dynaloader) {
	die "$0: no extension specified\n";
	}

	my $perl;
	my %extra_passthrough;

	if ($is_Win32) {
	my $build = getcwd();
	$perl = $^X;
	if ($perl =~ m#^\.\.#) {
	my $here = $build;
	$here =~ s{/}{\\}g;
	$perl = "$here\\$perl";
	}
	(my $topdir = $perl) =~ s/\\[^\\]+$//;
	# miniperl needs to find perlglob and pl2bat
	$ENV{PATH} = "$topdir;$topdir\\win32\\bin;$ENV{PATH}";
	my $pl2bat = "$topdir\\win32\\bin\\pl2bat";
	unless (-f "$pl2bat.bat") {
	my @args = ($perl, "-I$topdir\\lib", ("$pl2bat.pl") x 2);
	print "@args\n";
	system(@args) unless defined $::Cross::platform;
	}

	print "In $build";
	foreach my $dir (@dirs) {
	chdir($dir) or die "Cannot cd to $dir: $!\n";
	(my $ext = getcwd()) =~ s{/}{\\}g;
	FindExt::scan_ext($ext);
	FindExt::set_static_extensions(split ' ', $Config{static_ext});
	chdir $build
	or die "Couldn't chdir to '$build': $!"; # restore our start directory
	}

	my @ext;
	push @ext, FindExt::static_ext() if $static;
	push @ext, FindExt::dynamic_ext() if $dynamic;
	push @ext, FindExt::nonxs_ext() if $nonxs;
	push @ext, 'DynaLoader' if $dynaloader;

	foreach (sort @ext) {
	if (%incl and !exists $incl{$_}) {
	#warn "Skipping extension $_, not in inclusion list\n";
	next;
	}
	if (exists $excl{$_}) {
	warn "Skipping extension $_, not ported to current platform";
	next;
	}
	push @extspec, $_;
	if($_ eq 'DynaLoader' and $target !~ /clean$/) {
	# No, we don't know why nmake can't work out the dependency chain
	push @{$extra_passthrough{$_}}, 'DynaLoader.c';
	} elsif(FindExt::is_static($_)) {
	push @{$extra_passthrough{$_}}, 'LINKTYPE=static';
	}
	}

	chdir '..'
	or die "Couldn't chdir to build directory: $!"; # now in the Perl build
	}
	elsif ($is_VMS) {
	$perl = $^X;
	push @extspec, (split ' ', $Config{static_ext}) if $static;
	push @extspec, (split ' ', $Config{dynamic_ext}) if $dynamic;
	push @extspec, (split ' ', $Config{nonxs_ext}) if $nonxs;
	push @extspec, 'DynaLoader' if $dynaloader;
	}

	{
	# Cwd needs to be built before Encode recurses into subdirectories.
	# Pod::Simple needs to be built before Pod::Functions
	# This seems to be the simplest way to ensure this ordering:
	my (@first, @other);
	foreach (@extspec) {
	if ($_ eq 'Cwd' \|\| $_ eq 'Pod/Simple') {
	push @first, $_;
	} else {
	push @other, $_;
	}
	}
	@extspec = (@first, @other);
	}

	if ($Config{osname} eq 'catamount' and @extspec) {
	# Snowball's chance of building extensions.
	die "This is $Config{osname}, not building $extspec[0], sorry.\n";
	}

	foreach my $spec (@extspec) {
	my $mname = $spec;
	$mname =~ s!/!::!g;
	my $ext_pathname;

	# Try new style ext/Data-Dumper/ first
	my $copy = $spec;
	$copy =~ tr!/!-!;
	foreach my $dir (@ext_dirs) {
	if (-d "$dir/$copy") {
	$ext_pathname = "$dir/$copy";
	last;
	}
	}

	if (!defined $ext_pathname) {
	if (-d "ext/$spec") {
	# Old style ext/Data/Dumper/
	$ext_pathname = "ext/$spec";
	} else {
	warn "Can't find extension $spec in any of @ext_dirs";
	next;
	}
	}

	print "\tMaking $mname ($target)\n";

	build_extension($ext_pathname, $perl, $mname,
	[@pass_through, @{$extra_passthrough{$spec} \|\| []}]);
	}

	sub build_extension {
	my ($ext_dir, $perl, $mname, $pass_through) = @_;

	unless (chdir "$ext_dir") {
	warn "Cannot cd to $ext_dir: $!";
	return;
	}

	my $up = $ext_dir;
	$up =~ s![^/]+!..!g;

	$perl \|\|= "$up/miniperl";
	my $return_dir = $up;
	my $lib_dir = "$up/lib";
	$ENV{PERL_CORE} = 1;

	my $makefile;
	if ($is_VMS) {
	$makefile = 'descrip.mms';
	if ($target =~ /clean$/
	&& !-f $makefile
	&& -f "${makefile}_old") {
	$makefile = "${makefile}_old";
	}
	} else {
	$makefile = 'Makefile';
	}

	if (!-f $makefile) {
	if (!-f 'Makefile.PL') {
	print "\nCreating Makefile.PL in $ext_dir for $mname\n";
	my ($fromname, $key, $value);
	if ($mname eq 'podlators') {
	# We need to special case this somewhere, and this is fewer
	# lines of code than a core-only Makefile.PL, and no more
	# complex
	$fromname = 'VERSION';
	$key = 'DISTNAME';
	$value = 'podlators';
	$mname = 'Pod';
	} else {
	$key = 'ABSTRACT_FROM';
	# We need to cope well with various possible layouts
	my @dirs = split /::/, $mname;
	my $leaf = pop @dirs;
	my $leafname = "$leaf.pm";
	my $pathname = join '/', @dirs, $leafname;
	my @locations = ($leafname, $pathname, "lib/$pathname");
	foreach (@locations) {
	if (-f $_) {
	$fromname = $_;
	last;
	}
	}

	unless ($fromname) {
	die "For $mname tried @locations in in $ext_dir but can't find source";
	}
	($value = $fromname) =~ s/\.pm\z/.pod/;
	$value = $fromname unless -e $value;
	}
	open my $fh, '>', 'Makefile.PL'
	or die "Can't open Makefile.PL for writing: $!";
	printf $fh <<'EOM', $0, $mname, $fromname, $key, $value;
	#-- buffer-read-only: t --

	# This Makefile.PL was written by %s.
	# It will be deleted automatically by make realclean

	use strict;
	use ExtUtils::MakeMaker;

	# This is what the .PL extracts to. Not the ultimate file that is installed.
	# (ie Win32 runs pl2bat after this)

	# Doing this here avoids all sort of quoting issues that would come from
	# attempting to write out perl source with literals to generate the arrays and
	# hash.
	my @temps = 'Makefile.PL';
	foreach (glob('scripts/pod*.PL')) {
	# The various pod*.PL extractors change directory. Doing that with relative
	# paths in @INC breaks. It seems the lesser of two evils to copy (to avoid)
	# the chdir doing anything, than to attempt to convert lib paths to
	# absolute, and potentially run into problems with quoting special
	# characters in the path to our build dir (such as spaces)
	require File::Copy;

	my $temp = $_;
	$temp =~ s!scripts/!!;
	File::Copy::copy($_, $temp) or die "Can't copy $temp to $_: $!";
	push @temps, $temp;
	}

	my $script_ext = $^O eq 'VMS' ? '.com' : '';
	my %%pod_scripts;
	foreach (glob('pod*.PL')) {
	my $script = $_;
	s/.PL$/$script_ext/i;
	$pod_scripts{$script} = $_;
	}
	my @exe_files = values %%pod_scripts;

	WriteMakefile(
	NAME => '%s',
	VERSION_FROM => '%s',
	%-13s => '%s',
	realclean => { FILES => "@temps" },
	(%%pod_scripts ? (
	PL_FILES => \%%pod_scripts,
	EXE_FILES => \@exe_files,
	clean => { FILES => "@exe_files" },
	) : ()),
	);

	# ex: set ro:
	EOM
	close $fh or die "Can't close Makefile.PL: $!";
	}
	eval {
	my $ftime = time - 4;
	utime $ftime, $ftime, 'Makefile.PL';
	};
	print "\nRunning Makefile.PL in $ext_dir\n";

	# Presumably this can be simplified
	my @cross;
	if (defined $::Cross::platform) {
	# Inherited from win32/buildext.pl
	@cross = "-MCross=$::Cross::platform";
	} elsif ($opts{cross}) {
	# Inherited from make_ext.pl
	@cross = '-MCross';
	}

	my @args = ("-I$lib_dir", @cross, 'Makefile.PL');
	if ($is_VMS) {
	my $libd = VMS::Filespec::vmspath($lib_dir);
	push @args, "INST_LIB=$libd", "INST_ARCHLIB=$libd";
	} else {
	push @args, 'INSTALLDIRS=perl', 'INSTALLMAN1DIR=none',
	'INSTALLMAN3DIR=none';
	}
	push @args, @$pass_through;
	_quote_args(\@args) if $is_VMS;
	print join(' ', @run, $perl, @args), "\n";
	my $code = system @run, $perl, @args;
	warn "$code from $ext_dir\'s Makefile.PL" if $code;

	# Right. The reason for this little hack is that we're sitting inside
	# a program run by ./miniperl, but there are tasks we need to perform
	# when the 'realclean', 'distclean' or 'veryclean' targets are run.
	# Unfortunately, they can be run after 'clean', which deletes
	# ./miniperl
	# So we do our best to leave a set of instructions identical to what
	# we would do if we are run directly as 'realclean' etc
	# Whilst we're perfect, unfortunately the targets we call are not, as
	# some of them rely on a $(PERL) for their own distclean targets.
	# But this always used to be a problem with the old /bin/sh version of
	# this.
	if ($is_Unix) {
	my $suffix = '.sh';
	foreach my $clean_target ('realclean', 'veryclean') {
	my $file = "$return_dir/$clean_target$suffix";
	open my $fh, '>>', $file or die "open $file: $!";
	# Quite possible that we're being run in parallel here.
	# Can't use Fcntl this early to get the LOCK_EX
	flock $fh, 2 or warn "flock $file: $!";
	print $fh <<"EOS";
	cd $ext_dir
	if test ! -f Makefile -a -f Makefile.old; then
	echo "Note: Using Makefile.old"
	make -f Makefile.old $clean_target MAKE='@make' @pass_through
	else
	if test ! -f Makefile ; then
	echo "Warning: No Makefile!"
	fi
	make $clean_target MAKE='@make' @pass_through
	fi
	cd $return_dir
	EOS
	close $fh or die "close $file: $!";
	}
	}
	}

	if (not -f $makefile) {
	print "Warning: No Makefile!\n";
	}

	if ($is_VMS) {
	_macroify_passthrough($pass_through);
	unshift @$pass_through, "/DESCRIPTION=$makefile";
	}

	if (!$target or $target !~ /clean$/) {
	# Give makefile an opportunity to rewrite itself.
	# reassure users that life goes on...
	my @args = ('config', @$pass_through);
	system(@run, @make, @args) and print "@run @make @args failed, continuing anyway...\n";
	}
	my @targ = ($target, @$pass_through);
	print "Making $target in $ext_dir\n@run @make @targ\n";
	my $code = system(@run, @make, @targ);
	die "Unsuccessful make($ext_dir): code=$code" if $code != 0;

	chdir $return_dir \|\| die "Cannot cd to $return_dir: $!";
	}

	sub _quote_args {
	my $args = shift; # must be array reference

	# Do not quote qualifiers that begin with '/'.
	map { if (!/^\//) {
	$_ =~ s/\"/""/g; # escape C<"> by doubling
	$_ = q(").$_.q(");
	}
	} @{$args}
	;
	}

	sub _macroify_passthrough {
	my $passthrough = shift;
	_quote_args($passthrough);
	my $macro = '/MACRO=(' . join(',',@$passthrough) . ')';
	@$passthrough = ();
	@$passthrough[0] = $macro;
	}