[GHC] #10844: CallStack should not be inlined

[GHC]

#10844: CallStack should not be inlined
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        Reporter:  nomeata           |                Owner:  gridaphobe
            Type:  task              |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.10.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1259
       Wiki Page:                    |
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Comment (by simonpj):

 The "expandable" thing means that it's ok to duplicate the let-bound thing
 if it makes a rule match.  In this case it's the string-append rule -- and
 that rule is probably worth firing even if it does mean a bit of string
 duplication.  (Of course it might also mean that the top-level binding
 ends up un-referenced in the end, so there's no duplication.   But the
 worst-case is a bit of string duplication which is probably ok.

 I don't understand why that wasn't happening.  And if it's not happening,
 maybe other similar Good Things are not happening, all unseen.  So fixing
 this might fix other unreported bugs.  Thanks for looking into it.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10844#comment:28>
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