Add sane last resort fallbacks to check_exe()

And clean up its interface.

diff --git a/Makefile.PL b/Makefile.PL
index 8cabdb8724009b8f203a668091c6fdfe5308da91..0a96f8793cf8fc870742a0f5da0a24663a877945 100644 (file)
--- a/Makefile.PL
+++ b/Makefile.PL
@@ -42,7 +42,12 @@ sub validate_exe {
 }
 
 sub check_exe {
- my ($desc, $arg_var, $config_var, $env_var, $preferred_path) = @_;
+ my (%args) = @_;
+
+ my $desc           = delete $args{desc};
+ my $arg_var        = delete $args{arg_var};
+ my $tries          = delete $args{try};
+ my $preferred_path = delete $args{preferred_path};
 
  my $exe;
 
@@ -57,10 +62,10 @@ sub check_exe {
   print "Forcing the use of $exe as the $desc.\n";
  } else {
   print "Checking for a valid $desc in the PATH... ";
-  $exe = validate_exe($Config{$config_var}, $preferred_path);
-  # Only fall back to env if we cannot find the one used to build perl.
-  if (not defined $exe and defined $ENV{$env_var}) {
-   $exe = validate_exe($ENV{$env_var}, $preferred_path);
+  for my $try (@$tries) {
+   next unless defined $try;
+   $exe = validate_exe($try, $preferred_path);
+   last if defined $exe;
   }
   if (defined $exe) {
    print "$exe\n";
@@ -101,11 +106,20 @@ my $pp = filter_argv PP => sub {
 if ($pp) {
  print "Forcing the pure-Perl implementation from the arguments passed to Makefile.PL.\n";
 } else {
- $cc = check_exe('C compiler', 'CC', 'cc', 'CC');
+ $cc = check_exe(
+  desc    => 'C compiler',
+  arg_var => 'CC',
+  try     => [ $Config{cc}, $ENV{CC}, 'cc' ],
+ );
  if (defined $cc) {
   my ($vol, $dir, $file) = File::Spec->splitpath($cc);
   my $preferred_path = File::Spec->catpath($vol, $dir, '');
-  $ld = check_exe('linker', 'LD', 'ld', 'LD', $preferred_path);
+  $ld = check_exe(
+   desc           => 'linker',
+   arg_var        => 'LD',
+   try            => [ $Config{ld}, $ENV{LD}, 'ld' ],
+   preferred_path => $preferred_path,
+  );
  }
 }