public inbox for gdb-patches@sourceware.org
 help / color / mirror / Atom feed
From: Tom Tromey <tom@tromey.com>
To: Simon Marchi <simon.marchi@efficios.com>
Cc: gdb-patches@sourceware.org
Subject: Re: [PATCH] gdbsupport, gdbserver, gdb: use -Wno-vla-cxx-extension
Date: Mon, 15 Apr 2024 10:22:07 -0600	[thread overview]
Message-ID: <87cyqq38b4.fsf@tromey.com> (raw)
In-Reply-To: <20240412175200.829114-1-simon.marchi@efficios.com> (Simon Marchi's message of "Fri, 12 Apr 2024 13:51:54 -0400")

>>>>> "Simon" == Simon Marchi <simon.marchi@efficios.com> writes:

Simon> When building with clang 18, I see:
Simon>       CXX    aarch64-linux-tdep.o
Simon>     /home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: error: variable length arrays in C++ are a Clang extension [-Werror,-Wvla-cxx-extension]
Simon>      1299 |       gdb_byte za_zeroed[za_bytes];
Simon>           |                          ^~~~~~~~
Simon>     /home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: note: read of non-const variable 'za_bytes' is not allowed in a constant expression
Simon>     /home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1282:10: note: declared here
Simon>      1282 |   size_t za_bytes = std::pow (sve_vl_from_vg (svg), 2);
Simon>           |          ^

Simon> Since we are using VLAs right now, that warning doesn't make sense for
Simon> us.  add `-Wno-vla-cxx-extension` to the list of warning flags we try to
Simon> enable.  If we ever choose to disallow VLAs, we can remove that flag.

I wonder if we should instead remove the use of VLAs.
Is it just the one spot?

Tom

  reply	other threads:[~2024-04-15 16:22 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-12 17:51 Simon Marchi
2024-04-15 16:22 ` Tom Tromey [this message]
2024-04-15 16:32   ` Luis Machado
2024-04-15 16:48   ` Simon Marchi
2024-04-16 22:56     ` Tom Tromey
2024-04-17 14:52       ` Simon Marchi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=87cyqq38b4.fsf@tromey.com \
    --to=tom@tromey.com \
    --cc=gdb-patches@sourceware.org \
    --cc=simon.marchi@efficios.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).