[GHC] #14970: GHC.Err.errorWithoutStackTrace produces stack trace when profiling enabled

[GHC]

#14970: GHC.Err.errorWithoutStackTrace produces stack trace when profiling enabled
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        Reporter:  rotaerk           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  libraries/base    |              Version:  8.2.2
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by osa1):

 * cc: simonmar (added)


Comment:

 Why do you think this is a bug? We're talking about two kinds of stacks
 here

 1. Stack trace constructed by user-provided `HasCallStack` constraints

 2. Stack trace constructed by the RTS and generated code via (sometimes
 auto-generated) `SCC` annotations (aka. "cost-centre stack")

 and it's quite possible that these two stack traces show different things,
 they have different purposes. `errorWithoutStackTrace` overrides (1) but
 it can't override (2), (2) is a lower-level thing.

 Paging simonmar as he made `error` include the CCS stack in profiling mode
 in Phab:D1426.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14970#comment:1>
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