From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark H Weaver <mhw@netris.org>
Subject: bug#31210: Perl graft breakage
Date: Thu, 19 Apr 2018 03:05:15 -0400
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	<20180418180850.GA11245@jasmine.lan> <87muy0iaxm.fsf@netris.org>
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In-Reply-To: <20180418205236.GA26365@jasmine.lan> (Leo Famulari's message of
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To: Leo Famulari <leo@famulari.name>
Cc: 31210@debbugs.gnu.org

Leo Famulari <leo@famulari.name> writes:

> On Wed, Apr 18, 2018 at 03:14:45PM -0400, Mark H Weaver wrote:
>> I suggest that we add a phase to the replacement 'perl' to install a
>> symlink from $out/lib/perl5/5.26.1 pointing to "5.26.2".
>> 
>> Would you like to try this, Leo, and push it if it solves the problem
>> for you?
>
> Thanks for your advice. The attached patch fixes the issue for me.
>
> I would have pushed it but there is one thing I don't understand. Before
> I set (replacement #f), the build would fail because the new phase was
> run twice, and symlinking fails because it is not "forced" (as in `ln
> -sf`). Is this expected behaviour?

The problem is that you should never use 'package/inherit' to create a
graft.  That leads to an infinite tower of grafts.  I'm surprised it
works at all, but it's definitely not right.  Use (package (inherit ...)
...) instead, and leave out the (replacement #f).

     Thanks!
       Mark