[GHC] #16078: Hide -Weverything warnings for GHCi internals

[GHC]

#16078: Hide -Weverything warnings for GHCi internals
-------------------------------------+-------------------------------------
        Reporter:  crockeea          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  low               |            Milestone:
       Component:  GHCi              |              Version:  8.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by crockeea):

 * version:  8.6.2 => 8.7


Old description:

> Consider
>
> Bar.hs
> {{{
> module Bar where
> }}}
>
> Main.hs
> {{{
> import Bar
>
> main :: IO ()
> main = print ""
> }}}
>
> `stack ghci Main.hs --ghc-options -Weverything` produces
>
> {{{
> ...
> GHCi, version 8.6.2: http://www.haskell.org/ghc/  :? for help
>
> <interactive>:1:1: warning: [-Wmissing-local-signatures]
>     Polymorphic local binding with no type signature:
>       _compileParsedExpr :: forall a. GHC.Types.IO a -> GHC.Types.IO a
>
> <interactive>:1:1: warning: [-Wmissing-import-lists]
>     The module `Prelude' does not have an explicit import list
> Loaded GHCi configuration from C:\Users\ericcro\Desktop\VPC-Key-
> Distribution\src\.ghci
>
> <no location info>: warning: [-Wmissing-home-modules]
>     Modules are not listed in command line but needed for compilation:
>         Bar
> [1 of 2] Compiling Bar              ( Bar.hs, interpreted )
> ...
> }}}
>
> Those three errors have nothing to do with my code, and seem to be
> related to the internals of how GHCi works. It would be nice to hide all
> three.

New description:

 Consider

 Bar.hs
 {{{
 module Bar where
 }}}

 Main.hs
 {{{
 import Bar

 main :: IO ()
 main = print ""
 }}}

 `ghci Main.hs -Weverything` produces

 {{{
 ...
 GHCi, version 8.7.20190113: http://www.haskell.org/ghc/  :? for help

 <interactive>:1:1: warning: [-Wmissing-local-signatures]
     Polymorphic local binding with no type signature:
       _compileParsedExpr :: forall a. GHC.Types.IO a -> GHC.Types.IO a

 <interactive>:1:1: warning: [-Wmissing-import-lists]
     The module `Prelude' does not have an explicit import list

 <no location info>: warning: [-Wmissing-home-modules]
     Modules are not listed in command line but needed for compilation:
         Bar
 [1 of 2] Compiling Bar              ( Bar.hs, interpreted )
 ...
 }}}

 Those three errors have nothing to do with my code, and seem to be related
 to the internals of how GHCi works. It would be nice to hide all three.

--

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16078#comment:4>
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