Brian Inglis
Sat Jan 9 22:16:04 GMT 2021

On 2021-01-09 12:58, Brian Inglis wrote:
> On 2021-01-09 11:23, Thomas Koenig via Cygwin wrote:
>> there is a branch of gfortran for implementing coarrays based on a
>> shared memory implementation instead of MPI, the devel_coarray/native
>> branch.
>> I tried it out on Cygwin, but it doesn't work there (hangs on the
>> first sync).
>> The branch uses pthread mutexes and condition variables
>> with PTHREAD_PROCESS_SHARED for synchronization between processes.
>> I also ran the attached test program, which gave the output
>> pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED)failed: No error
>> Is it correct that PTHREAD_PROCESS_SHARED is not supported on
>> Cygwin?  Is it supported for condition variables, or is the fact
>> that it is reported as working an oversight?
> The function is supported but that parameter is not implemented or tested and 
> returns EINVAL:
>> If PTHREAD_PROCESS_SHARED does not work, are there known workarounds?
> If you have the ability and time to work on this, one of the Cygwin 
> developers/maintainers may be able to assist.

It looks like there was nothing on this between implementation circa 2002 and:

Presumably your goal is to support or disqualify gfortran coarrays:

For more about Windows limitations and alternatives see:

and the internal page link target:

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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