ghc-7.6: weak symbols and ghci

Time to time internetz stumble upon a ghci bug which is seen as inability to load base haskell package:

Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... ghc: /usr/lib64/ghc-7.4.2/base-4.5.1.0/HSbase-4.5.1.0.o: unknown symbol `stat'
ghc: unable to load package `base'

But the bug was most popular across rare gentoo users. An interesting correlation!

This post is about the root of this problem: the gory implementation details of ghci dynamic loader down to libC and even ELF symbols!

Not scared? Fasten your belts and Read On!