Build failure with PETSc 3.23.x / SLEPc 3.23.x (works with 3.22.x)

[nicspalla]

Yambo currently builds successfully with PETSc/SLEPc 3.22.x, but compilation fails when using PETSc 3.23.x and SLEPc 3.23.x.

The issue appears to be related to API changes introduced in the PETSc/SLEPc 3.23 release series. As a result, Yambo cannot currently be built against the latest PETSc/SLEPc versions available in several package managers and HPC software stacks.

[sangallidavide]

See here for a fix: https://gitlab.com/lumen-code/lumen/-/blob/develop/src/linear_algebra/MATRIX_slepc.F?ref_type=heads#L386

[nicspalla]

@sangallidavide , thanks a lot for the information.

It's the same fix that I had identified as well, at least from the build perspective. I still needed to perform the numerical validation, but I'm confident it will work since it's the same fix you identified.

In addition, I also had to modify the file K_stored_in_a_nest_matrix.F.

As soon as I commit the changes, I'll show you the modification. I'd appreciate your feedback in case you spot any potential issues.

Thanks!

[sangallidavide]

Ok, good. Pity that we had to do the work twice :-)