Boost / NumPy / libpsl Cyclic Dependency Fix Option

[Michael Dickens]

Hi David (& MacPorts developers) - Yesterday, py*-numpy was added as a dependency of Boost (in order to make sure boost.numpy is built knowingly), which created a cyclic dependency: boost -> py27-numpy -> gcc7 -> cctools -> llvm-5.0 -> cmake -> curl -> libpsl -> gtk-doc -> source-highlight -> boost. The obvious places to create a subport are in boost (boost-numpy) and libpsl (libpsl-docs). Neither boost nor libpsl allows building just the subport parts; we have to build the whole port then discard the extra cruft. The greater discussion is documented in < https://trac.macports.org/ticket/55807 >, and I added you on CC yesterday as well as am writing this email top the greater MacPorts developers group. I added an attachment patch that creates the subport libpsl-docs in the libpsl Portfile, and it works nicely for me on my various test computers & I hope others try it out as well & give feedback. Given that it takes maybe a minute or 2 max to build libpsl -- as opposed to many minutes to build Boost -- I'm inclined to push my libpsl-docs subport as a quick fix to the problem. We can then work on a better solution if folks wish to do so. Although the libpsl port is openmaintainer, this is a significant change so I'd value your feedback on how to proceed -- as well as feedback from the greater MacPorts developer community. Thanks! - MLD