[FFmpeg-devel] [Jack-Devel] [PATCH] libavdevice: JACK demuxer

Olivier Guilyardi list
Mon Mar 16 02:00:31 CET 2009

M?ns Rullg?rd wrote:
> Olivier Guilyardi <list at samalyse.com> writes:
>> M?ns Rullg?rd wrote:
>>> Writing SMP-safe code using shared buffers without any form of memory
>>> barriers is next to impossible.  This is because the exact time and
>>> order in which writes happen is generally unpredictable.  If you claim
>>> to have solved this problem you'll have to show something better than
>>> hand-waving as proof.
>> M?ns, in regard to proofs, if you can write a test that uses the
>> jack ringbuffer, fails without memory barriers, and succeeds with
>> them, on the platform on your choice (x86, PowerPC, ARM, etc...), I
>> promise I'll buy you a beer.
>> I suspect no one on earth can do that.
> That nobody has seen it fail does not mean it will never happen.

Does this mean that you believe in something that nobody has ever seen?

What about the gods you mentioned in your reply to Paul then? Should I believe
in them because some say I should?

There are many religions that could use your argument.

> Please look up the word proof in your dictionary.

>From WordNet:

n 1: any factual evidence that helps to establish the truth of
     something; "if you have any proof for what you say, now
    is the time to produce it"

M?ns, can you provide a fact, not a theory or an argument, that "helps to
establish the truth" of your very own sentence: "Writing SMP-safe code using
shared buffers without any form of memory barriers is next to impossible."

In the field of programming, facts are the results of running a program. So
please write that program that fails or succeeds because of memory barriers,
using the jack ringbuffer.


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