[GHC] #15826: Allow registering (Source)Plugins through the GHC API

[GHC]

#15826: Allow registering (Source)Plugins through the GHC API
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        Reporter:  DanielG           |                Owner:  DanielG
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHC API           |              Version:  8.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  D5278
       Wiki Page:                    |
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Comment (by DanielG):

 I assume you mean `s/LoadedPlugin/StaticPlugin/` above? My patch doesn't
 change anything about how `LoadedPlugin`s are handled.

 Indeed since `StaticPlugin` doesn't have an associated `ModIface` only the
 `PluginRecompile` field can influence recompilation and that's intended.

 As for build products: right now I only intend to use plugins that extract
 information while GHC is compiling and not change anything.

 If someone decides to use a plugin that changes the build output I don't
 see how the situation is any different for `StaticPlugin` compared to
 `LoadedPlugin`. If the plugin changes the build output it must sutably
 declare `pluginRecompile`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15826#comment:9>
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