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From: "amonakov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug inline-asm/97708] Inline asm does not use the local register
 asm specified with register ... asm() as input
Date: Thu, 05 Nov 2020 10:30:17 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D97708

Alexander Monakov <amonakov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |amonakov at gcc dot gnu.org

--- Comment #24 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
Segher, did you really mean to mark the bug resolved/fixed?

FWIW, I think Jakub is using an overly broad interpretation of the intended
behavior. Stretching that logic, it's possible to argue that it's okay for =
GCC
to put an operand in a different register than its asm specification says as
long as the constraint matches. But that would lead to wrong code.

Given that the only supported use of local register variables is passing
operands to inline asm in specific registers, I really think that GCC shoul=
dn't
silently change the operand's location like that. The mismatching constraint
could be a result of a typo (or something like a botched refactoring), and =
the
compiler should help the user catch such errors.=