--- /dev/null
+package ExtUtils::HasCompiler;
+$ExtUtils::HasCompiler::VERSION = '0.012';
+use strict;
+use warnings;
+
+use base 'Exporter';
+our @EXPORT_OK = qw/can_compile_loadable_object/;
+our %EXPORT_TAGS = (all => \@EXPORT_OK);
+
+use Config;
+use Carp 'carp';
+use File::Basename 'basename';
+use File::Spec::Functions qw/catfile catdir/;
+use File::Temp qw/tempdir tempfile/;
+
+my $tempdir = tempdir(CLEANUP => 1);
+
+my $loadable_object_format = <<'END';
+#define PERL_NO_GET_CONTEXT
+#include "EXTERN.h"
+#include "perl.h"
+#include "XSUB.h"
+
+#ifndef PERL_UNUSED_VAR
+#define PERL_UNUSED_VAR(var)
+#endif
+
+XS(exported) {
+#ifdef dVAR
+ dVAR;
+#endif
+ dXSARGS;
+
+ PERL_UNUSED_VAR(cv); /* -W */
+ PERL_UNUSED_VAR(items); /* -W */
+
+ XSRETURN_IV(42);
+}
+
+#ifndef XS_EXTERNAL
+#define XS_EXTERNAL(foo) XS(foo)
+#endif
+
+/* we don't want to mess with .def files on mingw */
+#if defined(WIN32) && defined(__GNUC__)
+# define EXPORT __declspec(dllexport)
+#else
+# define EXPORT
+#endif
+
+EXPORT XS_EXTERNAL(boot_%s) {
+#ifdef dVAR
+ dVAR;
+#endif
+ dXSARGS;
+
+ PERL_UNUSED_VAR(cv); /* -W */
+ PERL_UNUSED_VAR(items); /* -W */
+
+ newXS("%s::exported", exported, __FILE__);
+}
+
+END
+
+my $counter = 1;
+my %prelinking = map { $_ => 1 } qw/MSWin32 VMS aix/;
+
+sub can_compile_loadable_object {
+ my %args = @_;
+
+ my $config = $args{config} || 'ExtUtils::HasCompiler::Config';
+ return if not $config->get('usedl');
+
+ my ($source_handle, $source_name) = tempfile(DIR => $tempdir, SUFFIX => '.c', UNLINK => 1);
+ my $basename = basename($source_name, '.c');
+
+ my $shortname = '_Loadable' . $counter++;
+ my $package = "ExtUtils::HasCompiler::$shortname";
+ printf $source_handle $loadable_object_format, $basename, $package or do { carp "Couldn't write to $source_name: $!"; return };
+ close $source_handle or do { carp "Couldn't close $source_name: $!"; return };
+
+ my $abs_basename = catfile($tempdir, $basename);
+ my $object_file = $abs_basename . $config->get('_o');
+ my $loadable_object = $abs_basename . '.' . $config->get('dlext');
+ my $incdir = catdir($config->get('archlibexp'), 'CORE');
+
+ my ($cc, $ccflags, $optimize, $cccdlflags, $ld, $ldflags, $lddlflags, $libperl, $perllibs) = map { $config->get($_) } qw/cc ccflags optimize cccdlflags ld ldflags lddlflags libperl perllibs/;
+
+ if ($prelinking{$^O}) {
+ require ExtUtils::Mksymlists;
+ ExtUtils::Mksymlists::Mksymlists(NAME => $basename, FILE => $abs_basename, IMPORTS => {});
+ }
+ my @commands;
+ if ($^O eq 'MSWin32' && $cc =~ /^cl/) {
+ push @commands, qq{$cc $ccflags $cccdlflags $optimize /I "$incdir" /c $source_name /Fo$object_file};
+ push @commands, qq{$ld $object_file $lddlflags $libperl $perllibs /out:$loadable_object /def:$abs_basename.def /pdb:$abs_basename.pdb};
+ }
+ elsif ($^O eq 'VMS') {
+ # Mksymlists is only the beginning of the story.
+ open my $opt_fh, '>>', "$abs_basename.opt" or do { carp "Couldn't append to '$abs_basename.opt'"; return };
+ print $opt_fh "PerlShr/Share\n";
+ close $opt_fh;
+
+ my $incdirs = $ccflags =~ s{ /inc[^=]+ (?:=)+ (?:\()? ( [^\/\)]* ) }{}xi ? "$1,$incdir" : $incdir;
+ push @commands, qq{$cc $ccflags $optimize /include=($incdirs) $cccdlflags $source_name /obj=$object_file};
+ push @commands, qq{$ld $ldflags $lddlflags=$loadable_object $object_file,$abs_basename.opt/OPTIONS,${incdir}perlshr_attr.opt/OPTIONS' $perllibs};
+ }
+ else {
+ my @extra;
+ if ($^O eq 'MSWin32') {
+ push @extra, "$abs_basename.def";
+ push @extra, '-l' . ($libperl =~ /lib([^.]+)\./)[0];
+ }
+ elsif ($^O eq 'cygwin') {
+ push @extra, catfile($incdir, $config->get('useshrplib') ? 'libperl.dll.a' : 'libperl.a');
+ }
+ elsif ($^O eq 'aix') {
+ $lddlflags =~ s/\Q$(BASEEXT)\E/$abs_basename/;
+ $lddlflags =~ s/\Q$(PERL_INC)\E/$incdir/;
+ }
+ push @commands, qq{$cc $ccflags $optimize "-I$incdir" $cccdlflags -c $source_name -o $object_file};
+ push @commands, qq{$cc $optimize $object_file -o $loadable_object $lddlflags @extra $perllibs};
+ }
+
+ for my $command (@commands) {
+ print "$command\n" if not $args{quiet};
+ system $command and do { carp "Couldn't execute $command: $!"; return };
+ }
+
+ # Skip loading when cross-compiling
+ return 1 if exists $args{skip_load} ? $args{skip_load} : $config->get('usecrosscompile');
+
+ require DynaLoader;
+ local @DynaLoader::dl_require_symbols = "boot_$basename";
+ my $handle = DynaLoader::dl_load_file($loadable_object, 0);
+ if ($handle) {
+ my $symbol = DynaLoader::dl_find_symbol($handle, "boot_$basename") or do { carp "Couldn't find boot symbol for $basename"; return };
+ my $compilet = DynaLoader::dl_install_xsub('__ANON__::__ANON__', $symbol, $source_name);
+ my $ret = eval { $compilet->(); $package->exported } or carp $@;
+ delete $ExtUtils::HasCompiler::{"$shortname\::"};
+ eval { DynaLoader::dl_unload_file($handle) } or carp $@;
+ return defined $ret && $ret == 42;
+ }
+ else {
+ carp "Couldn't load $loadable_object: " . DynaLoader::dl_error();
+ return;
+ }
+}
+
+sub ExtUtils::HasCompiler::Config::get {
+ my (undef, $key) = @_;
+ return $ENV{uc $key} || $Config{$key};
+}
+
+1;
+
+# ABSTRACT: Check for the presence of a compiler
+
+__END__
+
+=pod
+
+=encoding UTF-8
+
+=head1 NAME
+
+ExtUtils::HasCompiler - Check for the presence of a compiler
+
+=head1 VERSION
+
+version 0.012
+
+=head1 DESCRIPTION
+
+This module tries to check if the current system is capable of compiling, linking and loading an XS module.
+
+B<Notice>: this is an early release, interface stability isn't guaranteed yet.
+
+=head1 FUNCTIONS
+
+=head2 can_compile_loadable_object(%opts)
+
+This checks if the system can compile, link and load a perl loadable object. It may take the following options:
+
+=over 4
+
+=item * quiet
+
+Do not output the executed compilation commands.
+
+=item * config
+
+An L<ExtUtils::Config|ExtUtils::Config> (compatible) object for configuration.
+
+=item * skip_load
+
+This causes can_compile_loadable_object to not try to load the generated object. This defaults to true on a cross-compiling perl.
+
+=back
+
+=head1 AUTHOR
+
+Leon Timmermans <leont@cpan.org>
+
+=head1 COPYRIGHT AND LICENSE
+
+This software is copyright (c) 2014 by Leon Timmermans.
+
+This is free software; you can redistribute it and/or modify it under
+the same terms as the Perl 5 programming language system itself.
+
+=cut