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Re: [PATCH] Async signal safe TLS accesses
- From: "Carlos O'Donell" <carlos at redhat dot com>
- To: Rich Felker <dalias at aerifal dot cx>, Alexandre Oliva <aoliva at redhat dot com>
- Cc: Paul Pluzhnikov <ppluzhnikov at google dot com>, Andrew Hunter <ahh at google dot com>, "Joseph S. Myers" <joseph at codesourcery dot com>, GLIBC Devel <libc-alpha at sourceware dot org>
- Date: Mon, 02 Dec 2013 16:58:52 -0500
- Subject: Re: [PATCH] Async signal safe TLS accesses
- Authentication-results: sourceware.org; auth=none
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On 11/30/2013 01:32 PM, Rich Felker wrote:
> I'm against any attempt to make anything "safe" under async
> cancellation. Calling any library functions at all (other than to
> disable async cancellation) with async cancellation active is just a
> serious programming error. There are way too many things that can go
> wrong, and no good reason to do it.
I think we should make pthread_testcancel AS-Safe and guarantee that
in glibc to fix the POSIX design flaw and then file a bug with the
Austin group to have it on record (even if its promptly closed).
There are some cases where AS-Safety is useful, and I'd like to see
that small bubble extended just a little bit.
This is however an entirely different topic form the one at hand,
but since I saw your comment about pthread_testcancel, I wanted to
put the bug in your ear.
Cheers,
Carlos.