For anyone building gretl on MS Windows: I've added an MSYS2
dependency, namely mingw-w64-x86_64-dlfcn (or mingw-w64-i686-dlfcn for
a 32-bit build).
This contains libdl.dll -- a small library that adds POSIX
functionality for loading and querying modules, which is useful for
libgretl in figuring out what blas/lapack variant we're looking at.
The files pkglist.txt and pkglist32.txt at
are updated accordingly.