On my Debian testing machine, after gcc updated to

gcc (Debian 6.2.0-9) 6.2.0 20161019

I started getting linker errors complaining about -fPIC

Herbert Valerio Riedel pointed out on #hackage that the settings file has to be updated to cope with this.

So, the files

/opt/ghc/7.10.3/lib/ghc-7.10.3/settings

/opt/ghc/8.0.1/lib/ghc-8.0.1/settings

need to be updated to have the following values set

("C compiler flags", "-fno-PIE -fno-stack-protector"),
("C compiler link flags", "-no-pie"),
("ld flags", "-no-pie"),

The precise location of these files may differ on your machine.

Alan