Subject: Re: [boost] [interprocess] atomic_write32 on GCC/x86/x68_64 lacks memory barrier
From: Lars HagstrÃ¶m (lars_at_[hidden])
Date: 2014-08-11 10:53:08
Thanks very much for your help! I've learnt a lot today :-)
On Mon, Aug 11, 2014 at 4:17 PM, Peter Dimov <lists_at_[hidden]> wrote:
> Lars HagstrÃ¶m wrote:
>> Does that "memory" statement at the end add a fence both before and after
>> the assembly statement?
> Effectively. To be more precise, it turns the assembly statement into a
> compiler fence. "memory" tells the compiler to assume that the assembly
> code accesses and modifies memory in unpredictable ways, and the effect of
> that is basically a compiler fence.
> You should probably use the __asm__ and __volatile__ spellings as a matter
> of style though.
> Unsubscribe & other changes: http://lists.boost.org/
Boost list run by bdawes at acm.org, gregod at cs.rpi.edu, cpdaniel at pacbell.net, john at johnmaddock.co.uk