make_ext.pl: Phase out the use of Cross.pm

In the old cross-compilation model, lib/ for the target would
end up in xlib/; What Cross.pm did back then was change @INC
around a bit to have miniperl point to xlib; Additionally, it
was used to identify cross-compilation builds, and in make_ext.pl
to detect whenever a Makefile was from the host's build.

There is no longer any need for the first, and the second is now
a simple check for $Config{usecrosscompile}, it's still
possible for the hosts' Makefiles to be there, particularly
if the host was not compiled elsewhere using -Dmksymlinks,
like in Windows when targetting WinCE.

This commit changes make_ext.pl for cross-compiling builds
to only delete Makefiles when their CC != $Config{cc}.

diff --git a/make_ext.pl b/make_ext.pl
index c857130..98ed3cc 100644 (file)
--- a/make_ext.pl
+++ b/make_ext.pl
@@ -1,8 +1,8 @@
 #!./miniperl
 use strict;
 use warnings;
-use constant IS_CROSS => defined $::Cross::platform ? 1 : 0;
 use Config;
+use constant IS_CROSS => defined $Config::Config{usecrosscompile} ? 1 : 0;
 
 my $is_Win32 = $^O eq 'MSWin32';
 my $is_VMS = $^O eq 'VMS';
@@ -310,31 +310,32 @@ sub build_extension {
                }
            }
        }
-       if(IS_CROSS){
-           seek($mfh, 0, 0) or die "Cannot seek $makefile: $!";
-           while (<$mfh>) {
-               #this is used to stop the while loop early for efficiency when
-               #the line is reached, and possibly match a cross build
-               my $header = quotemeta '# These definitions are from config.sh (via ';
-               if(/^$header.+?
-                   (xlib[\/\\]
-                   $::Cross::platform\Q\/Config.pm\E)?\)\./x) {
-                   unless (defined $1){
-                       print "Deleting non-Cross makefile\n";
-                       close $mfh or die "close $makefile: $!";
-                       _unlink($makefile);
-                       {
-                           no warnings 'deprecated';
-                           goto NO_MAKEFILE;
-                       }
-                   } else { #have a cross makefile
-                       goto CROSS_OK_MF;
-                   }
-               }
-           } #catch breakage from future changes
-           die "non-standard makefile found in $mname";
-           CROSS_OK_MF:
-       }
+
+        if (IS_CROSS) {
+            # If we're cross-compiling, it's possible that the host's
+            # Makefiles are around.
+            seek($mfh, 0, 0) or die "Cannot seek $makefile: $!";
+            
+            my $cross_makefile;
+            while (<$mfh>) {
+                # XXX This might not be throughout enough.
+                # For example, it's possible to cause a false-positive
+                # if cross compiling on and for the Raspberry Pi,
+                # which is insane but plausible.
+                # False positives are really not troublesome, though;
+                # all they mean is that the module gets rebuilt.
+                if (/^CC = \Q$Config{cc}\E/) {
+                    $cross_makefile = 1;
+                    last;
+                }
+            }
+            
+            if (!$cross_makefile) {
+                print "Deleting non-Cross makefile\n";
+                close $mfh or die "close $makefile: $!";
+                _unlink($makefile);
+            }
+        }
     }
 
     if (!-f $makefile) {
@@ -441,17 +442,7 @@ EOM
        }
        print "\nRunning Makefile.PL in $ext_dir\n";
 
-       # Presumably this can be simplified
-       my @cross;
-       if (IS_CROSS) {
-           # Inherited from win32/buildext.pl
-           @cross = "-MCross=$::Cross::platform";
-       } elsif ($opts{cross}) {
-           # Inherited from make_ext.pl
-           @cross = '-MCross';
-       }
-
-       my @args = ("-I$lib_dir", @cross, 'Makefile.PL');
+       my @args = ("-I$lib_dir", 'Makefile.PL');
        if ($is_VMS) {
            my $libd = VMS::Filespec::vmspath($lib_dir);
            push @args, "INST_LIB=$libd", "INST_ARCHLIB=$libd";