[GHC] #9282: GHCi ignores .dyn_hi files

[GHC]

#9282: GHCi ignores .dyn_hi files
----------------------------------+-------------------------------------
       Reporter:  mietek          |             Owner:
           Type:  bug             |            Status:  new
       Priority:  normal          |         Milestone:
      Component:  GHCi            |           Version:  7.8.2
       Keywords:                  |  Operating System:  Unknown/Multiple
   Architecture:  x86_64 (amd64)  |   Type of failure:  Other
     Difficulty:  Unknown         |         Test Case:
     Blocked By:                  |          Blocking:
Related Tickets:                  |
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 With both `.o` and `.dyn_o` object files available, GHCi 7.8.2 ignores the
 dynamic object files.

 {{{
 $ cat >Foo.hs <<EOF
 module Foo where

 foo :: IO ()
 foo = print "Foo"
 EOF
 }}}
 {{{
 $ ghc -Wall -c -dynamic-too -o Foo.o Foo.hs
 }}}
 {{{
 $ ghci
 GHCi, version 7.8.2: http://www.haskell.org/ghc/  :? for help
 Loading package ghc-prim ... linking ... done.
 Loading package integer-gmp ... linking ... done.
 Loading package base ... linking ... done.
 > :l Foo
 [1 of 1] Compiling Foo              ( Foo.hs, interpreted )
 Ok, modules loaded: Foo.
 >
 }}}

 As '''rwbarton''' mentioned on IRC, the reason becomes apparent with `ghci
 -ddump-if-trace`
 {{{
 FYI: cannot read old interface file:
     mismatched interface file ways (wanted "dyn", got "")
 }}}

 This happens both on OS X and Linux.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9282>
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