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Re: Implement C11 _Atomic
- From: Andrew MacLeod <amacleod at redhat dot com>
- To: "Joseph S. Myers" <joseph at codesourcery dot com>
- Cc: Hans-Peter Nilsson <hp at bitrange dot com>, gcc-patches at gcc dot gnu dot org
- Date: Thu, 21 Nov 2013 11:49:27 -0500
- Subject: Re: Implement C11 _Atomic
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On 11/21/2013 11:32 AM, Joseph S. Myers wrote:
I was just about to point out that :-) that would be a
shortcoming... 4.9 C++11 atomics do not use the same mechanism yet, so
they would still behave the same as 4.8 C++ atomics, even with the
override present.... C11 _Atomic variables would be the only beneficiary
at this point of the override.
On Thu, 21 Nov 2013, Andrew MacLeod wrote:
I'm trying to avoid ABI breakage of course. I'd rather not have
to ask people not to use _Atomic with 4.9 for CRIS ports using
official releases or have ABI breakage with the next release.
Maybe there's one other port in the same situation...
None I am aware of, but that doesn't mean much :-)
It has been suggested that hppa may have interesting issues for atomics -
but I'd think atomics support for it in GCC would mainly be for GNU/Linux,
where you have kernel helpers that may avoid the issues with the
Note that if you want libstdc++ atomics to be ABI compatible with C
atomics then there may be more work to do on that side (again, there are
pieces on the branch).