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From: "dave.anglin at bell dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug libstdc++/114103] FAIL: 29_atomics/atomic/lock_free_aliases.cc 
 -std=gnu++20 (test for excess errors)
Date: Mon, 26 Feb 2024 12:21:17 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114103

--- Comment #4 from dave.anglin at bell dot net ---
On 2024-02-26 5:54 a.m., redi at gcc dot gnu.org wrote:
> I assume the problem is that the ATOMIC_xxx_LOCK_FREE macros have value 1=
 not
> 2, so they're not unconditionally lock-free.
>
> Are any of the atomic integer types always lock-free for this target?
No.=C2=A0 The only "lock free" operations are load and clear word/double wo=
rd.

On linux, we fudge the support in the kernel where we can disable interrupts
but the operation
still can spin.=