[GHC] #14103: Retypechecking the loop in --make mode is super-linear when there are many .hs-boot modules

[GHC]

#14103: Retypechecking the loop in --make mode is super-linear when there are many
.hs-boot modules
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        Reporter:  duog              |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.3
      Resolution:                    |             Keywords:  hs-boot
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 niteria):

 If there's a cleaner way to do it, I'm all for it. I was conservative with
 my fix, because there was some code I didn't understand and I didn't want
 to change the behavior.

 For example:
 https://phabricator.haskell.org/diffusion/GHC/browse/master/compiler/main/GhcMake.hs;14457cf6a50f708eecece8f286f08687791d51f7$895-905

 If there are loops with multiple (say A.hs-boot, B.hs-boot, C.hs-boot) hs-
 boot modules, it would extract a cycle with A.hs-boot, B.hs-boot, C.hs-
 boot, a cycle with B.hs-boot, C.hs-boot, and a cycle with C.hs-boot. Why?
 I don't know.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14103#comment:1>
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