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Date: Sat, 8 Feb 2025 12:09:40 -0800
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Subject: Re: [PATCH v2] rust: alloc: satisfy `aligned_alloc` requirements
To: Alejandro Colomar <alx@kernel.org>
Cc: DJ Delorie <dj@redhat.com>, Eric Blake <eblake@redhat.com>,
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From: Paul Eggert <eggert@cs.ucla.edu>
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On 2025-02-08 11:19, Alejandro Colomar wrote:
> I wonder why glibc silently overaligns aligned_alloc() without reporting
> an error for an alignment of 2, while it reports an error for an
> alignment of 3.  It doesn't make much sense at first glance.

Why doesn't it make sense?

If the underlying memory management system supports only some 
power-of-two alignments including one alignment greater than 2, it is 
easy to support alignment of 2 by overaligning, but it is not possible 
to support an alignment of 3.