+ -- On a Win32 installation we execute the hsc2hs binary directly,
+ -- with no --cc flags, so we'll call locateGhc here, which will
+ -- succeed, via getExecDir.
+ --
+ -- On a Unix installation, we'll run the wrapper script hsc2hs.sh
+ -- (called plain hsc2hs in the installed tree), which will pass
+ -- a suitable C compiler via --cc
+ --
+ -- The in-place installation always uses the wrapper script,
+ -- (called hsc2hs-inplace, generated from hsc2hs.sh)