Re: [PATCH] MIPS: Fix PR target/98491 (ChangeLog)

[Richard Sandiford <richard.sandiford@arm.com>]

Xi Ruoyao via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
>> > > > I can't understand the comment either.  To me it looks like it's
>> > > > possible to
>> > > > remove this "if (MSA_SUPPORTED_P (mode)) return 0;"

I think the point is that the MSA loads and stores only have a 10-bit
offset field instead of the usual 16-bit offset field and so the usual
approaches to handling symbolic addresses won't work.

>> > > > 
>> > > > CC Robert to get some help.
>> > > Happy new lunar year folks.
>> > > 
>> > > I found a newer email address of Robert.  Hope it is still being used.
>> > > 
>> > > Could someone update MAINTAINERS file by the way?
>> > If you have an updated email address, I can reach out to Robert and see
>> > if he wants his entry updated or removed.
>> 
>>  His latest reply in gcc mail lists used Robert.Suchanek@mips.com.  But when I
>> sent mail to it, the mail was just rejected with "access denied".  Google told
>> me Office 365 mail service (used by mips.com) rejects mail to deleted accounts
>> with "access denied". So I'm not sure if this email address is invalid again,
>> or
>> Office 365 just dislikes me...
>
> Hi Jeff,
>
> I think it's better to just fix the out-of-bound array access now by special
> casing MAX_MACHINE_MODE, if we can't figure out if this entry should be removed.
> Either in MSA_SUPPORTED_P or in mips_symbol_insns.
>
> It's really "irrational" to leave such a obvious programming error in new GCC 11
> release...  And I've built a Linux system (in Linux From Scratch way, X11 was
> built and it runs correctly now) on the Loongson 3A4000 with patched GCC-10.2.0,
> and "-O3 -mmsa" in CFLAGS for most packages so the change should be OK.

Yeah, agreed.  I think the mips_symbol_insns patch is the right one,
so I've pushed to it trunk.  I think it's also worth backporting
to release branches, but let me know how far back you've tested it.

Thanks for the patch.

Richard