[GHC] #10627: Regression: cabal install of numeric-prelude hangs

[GHC]

#10627: Regression: cabal install of numeric-prelude hangs
-------------------------------------+-------------------------------------
        Reporter:  George            |                   Owner:
            Type:  bug               |                  Status:  merge
        Priority:  high              |               Milestone:  7.10.2
       Component:  Compiler          |                 Version:  7.10.2-rc2
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash                              |               Test Case:
      Blocked By:                    |  simplCore/should_compile/T10627
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:
-------------------------------------+-------------------------------------

Comment (by simonpj):

 Replying to [comment:20 George]:
 > Do we understand why this worked as recently as June 1st?

 No, I'm not sure.

 >  Also, why would the compiler hang without this fix? Just curious.

 It's the knot-tying in `CoreSubst.simplRecBndrs`.  Did you read `Note
 [Substitute lazily]` referred to in the commit message?

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10627#comment:21>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler