[m-rev.] for pre-commit review: workaround Mantis bug #453

[Julien Fischer]

On Sun, 19 Jan 2020, Peter Wang wrote:

> On Sun, 19 Jan 2020 20:22:20 +1100 (AEDT), Julien Fischer <jfischer at opturion.com> wrote:
>>
>> On Sun, 19 Jan 2020, Peter Wang wrote:
>>
>>> On Sun, 19 Jan 2020 18:12:02 +1100 (AEDT), Julien Fischer <jfischer at opturion.com> wrote:
>>>>
>>>> For pre-commit review by Peter.
>>>>
>>>> In particular:
>>>>
>>>> - should we instead handle this by forcing the use of gcc -O0 in asm_fast
>>>> grades on affected systes?
>>>
>>> Only in PIC mode.
>>
>> So, force gcc -O0 in PIC mode only as opposed to this diff?
>
> Yes.

Unfortunately, it doesn't work.  The only way I can get an asm_fast.gc
installation that passes the test suite is by using '--linkage static'.
(This is with GCC 6 on Debian 9.)

I propose that we simply use 'reg' as the default LLDS base grade on the
affected systems.  Furthermore, we make 'hlc' the default base grade
on systems where the default LLDS base grade is 'reg'.

Given that this only affects i*86 systems, I don't think it's worth
spending much further effort on it, at least for the purposes of the
20.01 release.

Julien.