When compiling and linking files in ghci, we keep adding rpath arguments
to the linker command invoation. If those are identical we should nub them out.
Otherwise we not only risk overflowing the argument limit, but also embed huge amounts
of identical rpath values into the dynamic library, eventually leading to the overflow
of the load command size limit, due to the number of rpath entries alone.
A further improvement could be to pass -Xlinker -dead_strip_dylibs; that however
might be stipping too aggressively, and potentially lead to missing symbols?
For the time being I sugget to only do the nubbing and if need be to provide
-Wl,-dead_strip_dylibs when invoking ghci.