bug in lang/perl5 5.18.0?

[Amitai Schlair <schmonz%schmonz.com@localhost>]

On NetBSD/i386 6.1, with lang/perl5 5.18.0, I have a reproducible
build problem in www/ikiwiki. The problem didn't occur with 6.1 and
5.16.3, nor can I recall any previously problematic Perl-and-NetBSD
combination.

The problem:

    $ make
    [...]
    building wishlist/watched_pages.mdwn
    [hangs here]

Variant of the problem:

    $ make 2>&1 | tee ikiwiki-netbsd6.1-perl5.18-build.log
    scanning tips/github.mdwn
    scanning
    [hangs here, which is a bit earlier in the build]

With either variant, I can ktrace the make invocation and it doesn't
change the outcome further (phew!).

Perl's tests are not all passing in our 5.18.0 package. I never tried
running them under previous versions, though, so I can't tell whether
the test failures (there are a whole bunch) are telling me anything
important. Are the Perl self-tests generally expected to pass?

kdump output from the first variant, including my Ctrl-C:

<URL:http://www.netbsd.org/~schmonz/ikiwiki-netbsd6.1-perl5.18-build-dump.txt>