[GHC] #7478: setSessionDynFlags does not always work

[GHC]

#7478: setSessionDynFlags does not always work
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        Reporter:  edsko             |            Owner:
            Type:  bug               |           Status:  new
        Priority:  highest           |        Milestone:  7.8.1
       Component:  Compiler          |          Version:  7.7
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:  ghc-api/T7478     |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by bennofs):

 Replying to [comment:11 MikolajKonarski]:
 > BTW, right now (I don't know how it was before) calling
 `setSessionDynFlags` causes significant memory leaks, visible already in
 tests with a couple hundred modules and calls. If anybody is interested, I
 can try to extract a test from my code that uses GHC API, but it's GHC
 version dependent, etc., so I'd rather not do it until anybody is actively
 looking at this. But it's straightforward: basically, in a loop:
 >
 > {{{
 > setSessionDynFlags flags
 > setTargets yetAnotherSIngleModule
 > load LoadAllTargets
 > }}}
 >
 >
 >
 > Even if we load 100 of modules and then just keep reloading the same
 module, memory will increase all the time.

 I can confirm this. I have a workaround for that problem in
 https://github.com/bennofs/ghc-
 server/blob/master/src/Server/Configure.hs#L117, which suggests that the
 problem is with reloading the package database.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7478#comment:12>
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