From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH] Makefile: add option to disable automatic dependency
 generation
Date: Fri, 18 Nov 2011 00:21:51 -0600
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Cc: Nguyen Thai Ngoc Duy <pclouds@gmail.com>,
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To: Junio C Hamano <gitster@pobox.com>
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Junio C Hamano wrote:

> Eek. At least at the end user UI level, couldn't we do this as a tristate?
> E.g. "YesPlease" (or anything that begins with Y if you are ambitious) to
> explicitly enable, empty (or "auto") to autodetect, and anything else to
> decline?

Ah, I didn't mind the UI so much.  Handling

	COMPUTE_HEADER_DEPENDENCIES_FORCE = (yes | no | auto)

should be doable.  I'd suggest making any other value error out, so
typos don't result in mysterious behavior.

> Even better, couldn't we either (1) rearrange .dep/ files somehow, so that
> compiler difference does not matter

Yes, I'm working on an incantation all the compilers like (it
shouldn't be hard --- adding an -MQ option should be enough, but I
want to understand the bug first).  But even with such a fix, I think
it will be important to have a way to turn the feature off.  When
someone using a compiler without -MMD support reports a bug, wouldn't
it be nice to be able to reproduce it?