From: Keith Seitz <keiths@redhat.com>
To: Simon Marchi <simon.marchi@polymtl.ca>,
Simon Marchi <simon.marchi@efficios.com>,
gdb-patches@sourceware.org
Subject: Re: [PATCH] gdb: work around negative DW_AT_data_member_location GCC 11 bug
Date: Wed, 26 Jan 2022 12:18:31 -0800 [thread overview]
Message-ID: <a33d94be-0dea-6442-00e1-8f1c33e7d981@redhat.com> (raw)
In-Reply-To: <e9b21bdc-6673-b659-a02e-a5a792996c56@polymtl.ca>
On 1/26/22 11:34, Simon Marchi wrote:
>
> In this case, we want to handle a very specific known bug by a specific
> compiler. We know that GCC meant 0 and not -1. But I wouldn't turn any
> negative value into 0, because that might not be the value the compiler
> intended. For example, another compiler could put -4 when it meant 4.
> If we turned that into 0, we would just add to the confusion.
>
> In fact, I am tempted to add a producer check and only apply the fixup
> if the producer is gcc 11.
>
> Since GDB doesn't know how to handle negative data member offsets (if
> that's even possible), I think that if we encounter a negative offset
> (other than the case above), we should just emit a complaint and leave
> the field's location as unknown.
All fair points; thank you for the explanation.
Keith
next prev parent reply other threads:[~2022-01-26 20:18 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-29 15:37 Simon Marchi
2022-01-26 17:45 ` Simon Marchi
2022-01-26 18:17 ` Keith Seitz
2022-01-26 18:30 ` Keith Seitz
2022-01-26 19:34 ` Simon Marchi
2022-01-26 19:38 ` Kevin Buettner
2022-01-26 19:40 ` Simon Marchi
2022-01-26 20:18 ` Keith Seitz [this message]
2022-01-26 19:18 ` Simon Marchi
2022-01-26 20:23 ` Keith Seitz
2022-01-26 19:49 ` Bruno Larsen
2022-01-26 19:58 ` Simon Marchi
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