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Date: Thu, 21 Apr 2022 18:47:41 +0300
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From: Eli Zaretskii <eliz@gnu.org>
To: Tom Tromey <tromey@adacore.com>
Cc: gdb-patches@sourceware.org
In-Reply-To: <20220421143926.2550856-1-tromey@adacore.com> (message from Tom
 Tromey via Gdb-patches on Thu, 21 Apr 2022 08:39:26 -0600)
Subject: Re: [PATCH] Handle encoding failures in Windows thread names
References: <20220421143926.2550856-1-tromey@adacore.com>
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> Date: Thu, 21 Apr 2022 08:39:26 -0600
> From: Tom Tromey via Gdb-patches <gdb-patches@sourceware.org>
> Cc: Tom Tromey <tromey@adacore.com>
> 
> Internally at AdaCore, we noticed that the new Windows thread name
> code could fail.  First, it might return a zero-length string, but in
> gdb conventions it should return nullptr instead.  Second, an encoding
> failure could wind up showing replacement characters to the user; this
> is confusing and not useful; it's better to recognize such errors and
> simply discard the name.  This patch makes both of these changes.

I suggest to explain in a comment how this code detects encoding
failures.  The documentation of WideCharToMultiByte is not simple to
understand in this regard, and "used_default" is not expressive enough
to explain its role here, so I suggest not to rely on the reader to
know those subtleties.

Thanks.