On Mon, Apr 09, 2018 at 10:58:13PM +0200, Thomas Koenig wrote: > > On Mon, Apr 09, 2018 at 10:10:13PM +0200, Thomas Koenig wrote: > >> > >> the attached patch removes the parallel annotation from DO CONCURRENT. > >> As discussed in the PR, the autoparallellizer currently generates > >> wrong code. The only feasible way is to disable the annotation for > >> gcc-8 and work on the wrong-code issues for gcc-9. This is an 8 > >> regression. > >> > >> Regression-tested. OK for trunk? > >> > > > > Yes. > > Thanks for the review! > > However, just as I was about to commit, I thought of something else > and, hopefully, better. > > The underlying problem is that the annotation does not go together > with -ftree-parallelize-loops - so let's simply not set it if that > flag is set. > > This way, we can avoid speed regressions for people who do not use > -ftree-parallelize-loops, and it will be possible to downgrade the > PR to a missed-optimization bug; it is also not necessary to xfail > vect-do-concurrent-1.f90 > > Regression-tested. OK for trunk, for this version?
In reviewing the PR audit trailing, I thought Richard indicated the problem is in the autopar stage in the middle. Removing the annotation simply prevents gfortran's DO CURRENT from a middle in bug. I'm fine with the new patch. I'll leave it up to you to decide which is preferred. -- Steve
