[GHC] #3693: Show stack traces

[GHC]

#3693: Show stack traces
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        Reporter:  jpet              |            Owner:
            Type:  feature request   |           Status:  new
        Priority:  normal            |        Milestone:  7.6.2
       Component:  Runtime System    |          Version:  6.10.4
      Resolution:                    |         Keywords:
Operating System:  Unknown/Multiple  |     Architecture:  Unknown/Multiple
 Type of failure:  None/Unknown      |       Difficulty:  Unknown
       Test Case:                    |       Blocked By:
        Blocking:                    |  Related Tickets:
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Comment (by scpmw):

 Great, thanks! I will start with splitting things up then. Unless there's
 other preferences I will submit the patches into a
 [https://github.com/scpmw/ghc/commits/profiling-import GitHub branch].
 That way, we don't have to spam this ticket with individual patches - and
 can document all interesting design choices in the commit message along
 the way.

 Would be good to get feedback on the initial
 [https://github.com/scpmw/ghc/commit/d9df7b8b0fc46b344b6060800955e8f50110dbbb
 source notes patch], as that's probably the piece of code with the highest
 chance of screwing things up in subtle ways. I am currently trying again
 to hunt down any further Core optimization behaviour changes due to source
 notes, but this version already works very well in my experience.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/3693#comment:46>
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