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Date: Wed, 24 Feb 2021 23:00:14 +0100 (CET)
From: "Maciej W. Rozycki" <macro@orcam.me.uk>
To: Jim Wilson <jimw@sifive.com>
cc: Jiaxun Yang <jiaxun.yang@flygoat.com>, GCC Development <gcc@gcc.gnu.org>, 
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Subject: Re: HELP: MIPS PC Relative Addressing
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On Wed, 24 Feb 2021, Jim Wilson wrote:

> >  I commented on it once, in the course of the FDPIC design project, and I
> > find it broken by design.  Sadly it has made it into the RISC-V psABI and
> > it is hard to revert at this time, too many places have started relying on
> > it.
> >
> 
> It was already a production ABI before you asked for the change.  And
> changing a production ABI is extremely difficult.  You were not the first
> to complain about this, and you probably won't be the last.

 Thanks for chiming in.

 I accepted it as a fact of life, but we don't have to follow the mistake 
with the MIPS psABI.  If you ever decide to have a RISC-V NewABI just as 
MIPS did at one point, then you can reevaluate the choices made.  At least 
there are no REL relocations there with RISC-V, it was a gross mistake to 
have them with MIPS o32.  I think we can try switching away from them with 
R6, or at least evaluate what would be required to do so.

  Maciej