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Subject: Re: cmp/diff
From: Paul Smith <psmith@gnu.org>
To: Bruno Haible <bruno@clisp.org>, Simon Josefsson <simon@josefsson.org>
Date: Sat, 26 Dec 2020 14:31:39 -0500
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On Sat, 2020-12-26 at 19:49 +0100, Bruno Haible wrote:
> Makefile rules are written both for automated execution and for the
> developers of a package. While for the automated execution of a unit
> test, "cmp expected.out actual.out" is sufficient, for a developer,
> "diff expected.out actual.out" is definitely nicer.

Agreed.

It could be possible for the configure script to check for diff and if
it's not provided, replace it with cmp in situations where we only need
to care about equality for correct processing (which is most places).

A message could be shown to the user saying that without diff it will
be hard for maintainers to assist if the configure fails.

However, that seems like a lot of effort for not much gain (for the GNU
project) so I'd suggest that if someone wanted something like that they
would need to provide the implementation.