[GHC] #13828: Re-linking is not avoided when -dynamic is used

[GHC]

#13828: Re-linking is not avoided when -dynamic is used
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        Reporter:  nh2               |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.2
  (Linking)                          |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by nh2):

 Note that this issue is not present when linking directly with `ghc
 --make`:

 {{{
 $ ghc --make -isrc app/Main.hs
 [1 of 2] Compiling Mymodule         ( src/Mymodule.hs, src/Mymodule.o )
 [2 of 2] Compiling Main             ( app/Main.hs, app/Main.o )
 Linking app/Main ...

 $ ghc --make -isrc app/Main.hs

 $
 }}}

 {{{
 $ ghc --make -isrc app/Main.hs -dynamic
 [1 of 2] Compiling Mymodule         ( src/Mymodule.hs, src/Mymodule.o )
 [2 of 2] Compiling Main             ( app/Main.hs, app/Main.o )
 Linking app/Main ...

 $ ghc --make -isrc app/Main.hs -dynamic

 $
 }}}

 Avoids relinking just fine.

 So I wonder what triggers it in the above case with cabal.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13828#comment:2>
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