one needs to understand the existing design first.

• (as far as I can see) currently Sage generates *.pc files for pkg-config, for blas, cblas, and lapack. This is done for Atlas (and for external blas/lapack fed in by SAGE_ATLAS_LIB ?). For openblas these *.pc files are basically all point to the same library.

• how are they used? Are they all used?

• is the description of SAGE_ATLAS_LIB outdated? I cannot imagine any need for f77 libraries in 2019...

Depends on #28883

CC: @embray @vbraun @sagetrac-tmonteil @mezzarobba @orlitzky @EmmanuelCharpentier @kiwifb @isuruf @mkoeppe

Component: build: configure

Author: Dima Pasechnik

Branch: 81bf522

Reviewer: Isuru Fernando

Issue created by migration from https://trac.sagemath.org/ticket/27870