cmakemake easyblock add -DCMAKE_

[bartoldeman]

cmakemake.py has this:

        sysroot = build_option('sysroot')
        if sysroot:
            options.append('-DCMAKE_SYSROOT=%s' % sysroot)
            self.log.info("Using absolute path to compiler commands because of alterate sysroot %s", sysroot)
            self.cfg['abs_path_compilers'] = True

however I think it would be better to patch cmake itself, ie. via cmake.py so that users don't need to add those options.

That means porting this technique to the easyblock cmake.py:

sed -i -e "s|@GENTOO_PORTAGE_GCCLIBDIR@|$EBROOTGENTOO/$(gcc -dumpmachine)/lib/|g" \
       -e "/@GENTOO_HOST@/d" \
       -e "s|@GENTOO_PORTAGE_EPREFIX@|${EPREFIX}/|g" \
       'Modules/Platform/{UnixPaths,Darwin}.cmake

combined with this patch:
https://gitweb.gentoo.org/repo/gentoo.git/tree/dev-util/cmake/files/cmake-3.14.0_rc3-prefix-dirs.patch

I'll work on a PR to put that logic in the cmake easyblock.

[boegel]

Only adding -DCMAKE_SYSROOT was a bit naive apparently, a better approach for CMakeMake is implemented in easybuilders/easybuild-easyblocks#2247 .

Patching the CMake installation itself so it also works properly outside of EasyBuild also makes sense, but is definitely trickier...

[boegel]

The patched CMakeMake isn't working out very well, patching CMake itself is probably a better idea indeed; see easybuilders/easybuild-easyblocks#2248 .

[boegel]

@bartoldeman We should try and get easybuilders/easybuild-easyblocks#2248 merged soon, let me know when you'd have some time to look into this together...