On Wed, Oct 02, 2024 at 11:26:10AM +0300, Jani Nikula wrote:
> On Tue, 01 Oct 2024, Brahmajit Das <brahmajit.xyz@xxxxxxxxx> wrote:
> > GCC 15 enables -Werror=unterminated-string-initialization by default.
> > This results in the following build error
> >
> > drivers/gpu/drm/display/drm_dp_dual_mode_helper.c: In function ‘is_hdmi_adaptor’:
> > drivers/gpu/drm/display/drm_dp_dual_mode_helper.c:164:17: error: initializer-string for array of
> > ‘char’ is too long [-Werror=unterminated-string-initialization]
> > 164 | "DP-HDMI ADAPTOR\x04";
> > | ^~~~~~~~~~~~~~~~~~~~~
> >
> > After discussion with Ville, the fix was to increase the size of
> > dp_dual_mode_hdmi_id array by one, so that it can accommodate the new
> > line character. This should let us build the kernel with GCC 15.
>
> Should be terminating NUL, not new line.
>
> >
> > Signed-off-by: Brahmajit Das <brahmajit.xyz@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/display/drm_dp_dual_mode_helper.c | 5 +++--
> > 1 file changed, 3 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c b/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c
> > index 14a2a8473682..295375868db6 100644
> > --- a/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c
> > +++ b/drivers/gpu/drm/display/drm_dp_dual_mode_helper.c
> > @@ -160,11 +160,12 @@ EXPORT_SYMBOL(drm_dp_dual_mode_write);
> >
> > static bool is_hdmi_adaptor(const char hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN])
> > {
> > - static const char dp_dual_mode_hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN] =
> > + //+1 to avaoid spurious -Werror=unterminated-string-initialization warning
>
> If we added comments for every little thing like this, there'd be more
> comments than code. ;)
I asked for a comment, otherwise I suspect I''d end up undoing this
after forgetting why it's there. OTOH maybe I'll get the "broken"
gcc upgrade before I look at this code again, which would solve
that particular problem.
>
> > + static const char dp_dual_mode_hdmi_id[DP_DUAL_MODE_HDMI_ID_LEN + 1] =
> > "DP-HDMI ADAPTOR\x04";
> >
> > return memcmp(hdmi_id, dp_dual_mode_hdmi_id,
> > - sizeof(dp_dual_mode_hdmi_id)) == 0;
> > + DP_DUAL_MODE_HDMI_ID_LEN) == 0;
> > }
> >
> > static bool is_type1_adaptor(uint8_t adaptor_id)
>
> --
> Jani Nikula, Intel
--
Ville Syrjälä
Intel
