On Fri, Sep 24, 2021 at 07:53:21AM -0700, Douglas Anderson wrote: > Apparently some compilers [1] cannot handle doing math on dereferenced > string constants at compile time. This has led to reports [2] of > compile errors like: > > In file included from drivers/gpu/drm/drm_edid.c:42:0: > ./include/drm/drm_edid.h:525:2: error: initializer element is not constant > ((((u32)((vend)[0]) - '@') & 0x1f) << 26 | \ > > Go back to the syntax I used in v4 of the patch series [3] that added > this code instead of what landed (v5). This syntax is slightly uglier > but should be much more compatible with varied compilers. > > [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69960#c18 > [2] https://lore.kernel.org/r/874kaabdt5.fsf@xxxxxxxxx/ > [3] https://lore.kernel.org/r/20210909135838.v4.4.I6103ce2b16e5e5a842b14c7022a034712b434609@changeid/ > > Fixes: d9f91a10c3e8 ("drm/edid: Allow querying/working with the panel ID from the EDID") > Reported-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx> > Reported-by: Srikanth Myakam <smyakam@xxxxxxxxxxxxx> > Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Not so nice, but apparently needed. Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
