Ghc 8.0.2

[tolysz]

base-4.9.1.0

System/Posix/Process/Internals.hs:12:18: error:
    Module ‘GHC.Conc’ does not export ‘Signal’

[RyanGlScott]

Do you mind giving us more detail about what environment you're running in? Because I have no problems building either the latest unix from Hackage or the latest commit from this repo using GHC 8.0.2 (and thus base-4.9.1.0) on 64-bit Linux.

As a sanity-check: you're using vanilla GHC 8.0.2, right? With no modifications?

[hvr]

The line in question is

import GHC.Conc (Signal)

and looking at GHC's source-code, we find

module GHC.Conc
    (
-- ...
#ifndef mingw32_HOST_OS
        , Signal, HandlerFun, setHandler, runHandlers
#endif
-- ...
  ) 

So the only case the error can be observed is when trying to compile unix on windows, which is not supported for unix. In fact, recent versions of unix.cabal contain

    if os(windows)
        -- This package currently supports neither Cygwin nor MinGW,
        -- therefore os(windows) is effectively not supported.
        build-depends: unbuildable<0
        buildable: False

Consequently, I come to the conclusion that this bug report is invalid. If you disagree, please reopen.

[peterbecich]

@tolysz , by any chance, did this error occur with GHCJS?