[BLAS] add metaport

[cenit]

Almost identical to LAPACK approach, I am suggesting this metaport to ease BLAS+LAPACK port override (macOS Accelerate framework is almost the only one working properly on the upcoming Apple Silicon)

[cenit]

Note: I added f90ffde commit to keep current BLAS setup also on macOS. It's an open question if we should use Apple Accelerate framework there by default (and in this case just reverting the commit and make blas depend on openblas(!osx)

[NancyLi1013]

Is it necessary to update Port-Version for other ports?

[cenit]

Any feedback here to consider for merging?

[NancyLi1013]

I noticed that Port-Version is not updated for some ports. I'm not sure if it is necessary to update it.

Note: Seems need to resolve the conflicts caused by shogun.

[cenit]

I noticed that Port-Version is not updated for some ports. I'm not sure if it is necessary to update it.

Note: Seems need to resolve the conflicts caused by shogun.

Ok but @ras0219 requested port version bump only for clapack, I assume the others are ok in this way

[cenit]

@NancyLi1013 may I ask why "requires:author-response"?

[NancyLi1013]

@cenit
Sorry for the late delay. We're on holiday in these days.
There were some conflicts caused by shogun before this. So I added the label. Seems you have solved them now. I will try to rerun and check the new results. I will remove this label if all CI checks have passed.

[NancyLi1013]

/azp run

[azure-pipelines]

No pipelines are associated with this pull request.

[NancyLi1013]

@cenit

Could you please resolve the conflicts and also merge master?

[NancyLi1013]

LGTM now, thanks for your PR @cenit.

[cenit]

@BillyONeal i copy-pasted same exact messages and behavior from the lapack port! But I will modify pr according to your review.

About the openblas(!osx), it’s a residual from the past. In the beginning I did a pr to exclude OpenBLAS and clapack from Ports using them on osx, because the accelerate framework was better. Then lapack-reference came and it superseded the behavior, to uniform platform better. This made OpenBLAS the default everywhere, too.
Now with the advent of arm64 arch for macOS the accelerate framework is very relevant again, so also an easy way to override vcpkg default to its own blas/lapack libs

[BillyONeal]

@Neumann-A Can you explain what those comments are saying that were added in #12464 ? It seems like the lapack port is trying to be both an indicator of use of a system outside-of-vcpkg provided lapack but it simultaneously wants clapack or lapack-reference to provide an implementation.

/cc @strega-nil

[Neumann-A]

@BillyONeal: there was a external/extern feature once but somebody did not like it. The idea was if you install lapack[core, extern] the lapack port simply checked if find_package(LAPACK) finds something. anyway the ports needs updating for the intel-mkl port which should also be able to supply blas/lapack functionality

[BillyONeal]

@Neumann-A I see, so the comment is just wrong and should be removed from both places?

[Neumann-A]

@BillyONeal: I still think the port should be used to test if find_package(BLAS/LAPACK) works. Maybe rename the project and remove the comment.

[BillyONeal]

@Neumann-A That's fine, I'm objecting to the comment, not the behavior

[strega-nil]

Thanks @cenit, this is great :)