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From: "gjl at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/90706] [9/10 Regression] Useless code
 generated for stack / register operations on AVR
Date: Wed, 29 Apr 2020 16:50:04 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D90706

--- Comment #9 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
(In reply to Berni from comment #8)
> I just compiled AVR gcc 9.3.0 and tested the code again. Still no
> improvement!


Don't expect anything from v9 (or from v10 for that matter). The problem is=
 in
the middle-end, and problems there that affect targets like avr will not be
fixed -- except in the rare case you manage to show that the issue affects a
target that is important enough and report it for that target.

And don't expect anything from v11+ either. The avr backend will likely be
removed from the compiler, see PR92729. The depreciation is for v11 and was=
n't
even worth a mention in the v10 release notes caveats
https://gcc.gnu.org/gcc-10/changes.html

The general recommendation is to switch to clang / llvm where the respective
backend is improving and has left experimental status;and is not suffering =
from
self-destruction...=