WIP status:

- macos
  - uses accelerate, don't build gfortran or lapack
  - suitesparse seems to compile ok
- linux
  - build gfortran with fpic & static libs
  - can build openblas blas&lapack with this gfortran and clang C compiler
  - can compile suitesparse with these static lapack/gfortran/quadmath libs
  - NOTE: unclear if this is completely safe, as libgfortran links to libstdc++ so we are assuming binary compatibility between the one we compiled for gfortran and the system one that is linked, but so far seems ok
- windows
  - build gfortran with fpic & static libs
  - build openblas blas&lapack with this gfortran and system gcc compiler fails at linking stage
  - best guess is mismatch between libstdc++ compiled by gfortran and system libstdc++

Possible ways forward (in ascending order of unmaintability):

- don't add suitesparse or any lapack/fortran-dependent libs (i.e. delete this branch)
- skip gfortran/openblas and only build suitesparse on mac
  - make suitesparse an optional build-time dependency of sme, only enable it for mac
- use system fortran compilers on linux/windows & statically link libgfortran/libquadmath
  - pass libs through to sme build & enable suitesparse
  - disable suitesparse & do not link these libs in sme wheel build (not PIC -> can't link in shared lib)
- use custom linux gfortran, need to pass lapack/gfortran libs all the way to sme build, but then can use them in the wheel
- try to do this on windows
  - either by fiddling with patches & config options when building gfortran such that it links with the system libstdc++
  - or by modifying the recipe for gcc & building our own complete fpic gcc msys2 toolchain

.github/workflows/release.yml

@@ -129,7 +129,7 @@ jobs:
       BOOST_B2_OPTIONS: "address-model=64"
       TBB_ENABLE_IPO: "OFF"
       VTK_OPTIONS: "-DFREETYPE_LIBRARY_RELEASE=/c/smelibs/lib/libQt6BundledFreetype.a -DFREETYPE_INCLUDE_DIR_freetype2=/c/smelibs/include/QtFreetype -DFREETYPE_INCLUDE_DIR_ft2build=/c/smelibs/include/QtFreetype"
-      GCC_VERSION: "gcc-11.4.0"
+      GCC_VERSION: "gcc-13.2.0"
 
     defaults:
       run: