https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70895
Thomas Schwinge <tschwinge at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |openacc
Status|UNCONFIRMED |WAITING
Last reconfirmed| |2016-05-02
CC| |cesar at gcc dot gnu.org,
| |nathan at gcc dot gnu.org,
| |tschwinge at gcc dot gnu.org
Assignee|unassigned at gcc dot gnu.org |tschwinge at gcc dot
gnu.org
Ever confirmed|0 |1
--- Comment #1 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
(In reply to Ralph Trenkler from comment #0)
> Created attachment 38389 [details]
> compiler configure command line, compiler call, program in f90, *.i-file
Thanks for that!
> Problem with OpenACC: The output of the attached fortran 90 program
> "acc-test-04.f90" is zero but not "pi" (3.14...), as it should be. The
> compiler version is 6.1.0.
There is no "copy(pi)" or "reduction(+:pi)" clause on the outer "acc parallel"
construct, so the offloaded computation of "pi" will not be copied back; hence
the result of zero. (Cesar CCed; please shout if I'm interpreting the OpenACC
2.0a specification wrongly.)
Also, due to the gang/worker/vector loop scheduling algorithm that's currently
used, you'll want to add explicit "gang worker vector" clauses to the one-level
"acc loop" construct. (Nathan CCed for your information.)
Do you have any further questions?
