Re: [PATCH] [v2] ALSA: asihpi: avoid write overflow check warning
From: Takashi Iwai
Date: Wed Mar 18 2026 - 12:31:51 EST
On Wed, 18 Mar 2026 13:40:07 +0100,
Arnd Bergmann wrote:
>
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> clang-22 rightfully warns that the memcpy() in adapter_prepare() copies
> between different structures, crossing the boundary of nested
> structures inside it:
>
> In file included from sound/pci/asihpi/hpimsgx.c:13:
> In file included from include/linux/string.h:386:
> include/linux/fortify-string.h:569:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning]
> 569 | __write_overflow_field(p_size_field, size);
>
> The two structures seem to refer to the same layout, despite the
> separate definitions, so the code is in fact correct.
>
> Avoid the warning by copying the two inner structures separately.
> I see the same pattern happens in other functions in the same file,
> so there is a chance that this may come back in the future, but
> this instance is the only one that I saw in practice, hitting it
> multiple times per day in randconfig build.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>
> v2: use correct union member
Applied now. Thanks.
Takashi