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From: David Chisnall <theraven@FreeBSD.org>
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Date: Wed, 8 Feb 2012 14:14:12 +0000
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Subject: NO_TLS flag for public headers
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Hi,

The xlocale changes in libc mean that a lot of things that were =
previously global state are now per-thread.  This includes some things =
that were used in ctype.h and are inlined.  We're now losing the benefit =
of inlining them because we now have to call into libc to get the =
per-thread values.  I'd like to use TLS for caching these things, but we =
currently have no equivalent of the NO_TLS flag for public headers.  I'd =
like to have a __NO_TLS that can be set in cdefs.h for architectures =
that don't have TLS support.

Any comments?  Objections?  Anyone want to propose a better place for it =
(or, indeed, add it, since I'm not entirely sure which architectures do =
lack TLS support...)

David=