From mboxrd@z Thu Jan  1 00:00:00 1970
From: Arun Isaac <arunisaac@systemreboot.net>
Subject: Why should build phases not return unspecified values?
Date: Sun, 17 Dec 2017 04:58:15 +0530
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Whenever we have a build phase that ends with a call (for example, to
substitute, chdir, symlink, etc) that returns an unspecified value, we
append a #t so that the return value is a boolean. However, the build
system, as it stands currently, does not mind an unspecified value, and
treats it as a success. As a result, forgetting to add a #t at the end
of custom phases is a common mistake. To fix this, I have submitted a
patch at https://debbugs.gnu.org/cgi/bugreport.cgi?bug=29745 that
modifies the build system to reject unspecified values as
failures.

However, IMO, the addition of #t at the end of certain phases, does not
contribute anything of value and we should simply be at peace with
phases returning unspecified values. Am I missing something here?

WDYT?