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 Thu, 4 Mar 2021 19:46:47 -0500
From: DJ Delorie <dj@redhat.com>
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: libc-alpha@sourceware.org, Richard.Earnshaw@arm.com
Subject: Re: [PATCH 08/16] malloc: Use global flag instead of function pointer
 dispatch for mtag
In-Reply-To: <8d9711a654bfe7a47ba743ab7e836118f8866f66.1614874816.git.szabolcs.nagy@arm.com>
 (message from Szabolcs Nagy on Thu, 4 Mar 2021 16:32:27 +0000)
Date: Thu, 04 Mar 2021 19:46:46 -0500
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Szabolcs Nagy <szabolcs.nagy@arm.com> writes:
> The definition of tag_new_usable is moved after chunk related
> definitions.

A couple thousand lines after, that is.  Perhaps it could go at the end
of the chunk related definitions, closer to the other tag functions?

> This refactoring also allows using mtag_enabled checks instead of
> USE_MTAG ifdefs when memory tagging support only changes code logic
> when memory tagging is enabled at runtime.

Are you relying on the compiler to do the work of the old #ifdefs for
platforms without USE_MTAG set?  I.e. are we sure that the compiled
binaries will have the mtag-related code optimized out?

Otherwise LGTM with the above caveats.

Reviewed-by: DJ Delorie <dj@redhat.com>