Bug #17639 for Module-Install: [PATCH] Module::Install breaks with proxy constant subroutines in perl-5.9.3

Running "perl Makefile.PL" in the attached Foo module (which includes Module-Install-0.56) works fine with perl-5.8.8, but with perl-5.9.3 it dies with the error: Not a GLOB reference at inc/Module/Install.pm line 91. BEGIN failed--compilation aborted at Makefile.PL line 3. The error arises because of the "use constant FOO => 1;" line in inc/Module/Install/PRIVATE.pm -- removing that line fixes it. The reason for this is that perl-5.9.3 introduced "proxy constant subroutines" (see perl593delta.pod) which are not full typeglobs until they are actually used. In the meantime, they are just SCALAR refs, hence the "not a GLOB ref" error. The attached patch fixes the error by eval()'ing the GLOB ref de-reference: if it isn't a GLOB ref then eval() returns undef and the item is ignored. Presumably that's not actually the best idea if the only thing in the extension being pre-loaded is constants, so you may want a better fix than this, but it works OK for extensions containing constants and other methods.

diff -ruN Module-Install-0.56.orig/lib/Module/Install.pm Module-Install-0.56/lib/Module/Install.pm --- Module-Install-0.56.orig/lib/Module/Install.pm 2006-02-08 14:04:18.000000000 +0000 +++ Module-Install-0.56/lib/Module/Install.pm 2006-02-14 12:03:33.540377600 +0000 @@ -88,7 +88,7 @@ my %seen_method; foreach my $obj ( @exts ) { while (my ($method, $glob) = each %{ref($obj) . '::'}) { - next unless defined *{$glob}{CODE}; + next unless defined eval { *{$glob}{CODE} }; next if $method =~ /^_/; next if $method eq uc($method); $seen_method{$method}++;