Re: [PATCH] GDB: aarch64: Use GCS features to calculate hash of struct aarch64_features

[Luis <luis.machado.foss@gmail.com>]

Hi!

On 17/09/2025 02:03, Thiago Jung Bauermann wrote:
> Luis noticed that when adding the gcs and gcs_linux members to struct
> aarch64_features in my Guarded Control Stack patch series, I neglected to
> modify struct hash<aarch64_features>::operator() to take them into account
> when computing its hash.
> 
> This can cause GDB to use the wrong aarch64_features object during a
> debugging session.
> 
> Regression tested on aarch64-linux-gnu.
> 
> Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33440
> Suggested-by: Luis <luis.machado.foss@gmail.com>
> ---
> 
> This should also be backported to the branch. Unfortunately I'm not able
> to set the target milestone in Bugzilla.
> 
>   gdb/arch/aarch64.h | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/gdb/arch/aarch64.h b/gdb/arch/aarch64.h
> index 679d845df74e..0fcdba7fb7d6 100644
> --- a/gdb/arch/aarch64.h
> +++ b/gdb/arch/aarch64.h
> @@ -94,6 +94,10 @@ namespace std
>   
>         /* SME2 feature.  */
>         h = h << 1 | features.sme2;
> +
> +      h = h << 1 | features.gcs;
> +      h = h << 1 | features.gcs_linux;
> +
>         return h;
>       }
>     };

Thanks for the patch, this is OK for both master and the branch.

Approved-By: Luis Machado <luis.machado.foss@gmail.com>