Help on LAPACKE integration

[tpadioleau]

Hi, I use some LAPACKE functions in a C++ project with CMake. I chose this API to avoid some ABI problems with the Fortran LAPACK but I am facing build system issues. Depending on the LAPACK provider:

• LAPACKE is not available
• LAPACKE symbols are found in the library providing LAPACK
• LAPACKE symbols are found in a dedicated library liblapacke.so

In practice I find it difficult to use in a C/C++ project. Also, CMake does not have a native support for LAPACKE but only LAPACK.

Do you have any advice ?

I was wondering if it would make sense to have only one implementation of LAPACKE that could adapt to any LAPACK provider ?

[martin-frbg]

I don't have any actual advice, but I notice that there are implementations of a FindLAPACKE.cmake out there, such as
https://github.com/optimad/bitpit/blob/master/external/LAPACKE/cmake/FindLAPACKE.cmake that do appear to address the question of whether it is bundled in the lapack library or provided as a standalone liblapacke.
(And the canonical place to raise this question would probably be https://github.com/Reference-LAPACK/lapack - OpenBLAS only bundles this reference implementation)

[tpadioleau]

Thanks for your prompt reply!

I don't have any actual advice, but I notice that there are implementations of a FindLAPACKE.cmake out there, such as https://github.com/optimad/bitpit/blob/master/external/LAPACKE/cmake/FindLAPACKE.cmake that do appear to address the question of whether it is bundled in the lapack library or provided as a standalone liblapacke.

Indeed some CMake modules exist on internet, I was actually using one of them. Unfortunately it could not find the directory of lapacke.h in a Spack installation. I am starting to write my own, likely less generic, but hopefully works for my setup.

(And the canonical place to raise this question would probably be https://github.com/Reference-LAPACK/lapack - OpenBLAS only bundles this reference implementation)

Sure I will do!

[ilayn]

Hi @tpadioleau

This is definitely not what you intended but I have been going through same struggles in a very restricted environment and created the C translation of LAPACK for the same purpose. In case you have the freedom, have a go at it https://github.com/ilayn/semicolon-lapack over any CBLAS interface providing library.