[GHC] #15730: SCC/HPC/CORE annotation can change the meaning of an expression

9 Oct 2018

      #15730: SCC/HPC/CORE annotation can change the meaning of an expression
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           Reporter:  int-index      |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  high           |         Milestone:
          Component:  Compiler       |           Version:  8.6.1
  (Parser)                           |
           Keywords:                 |  Operating System:  Unknown/Multiple
       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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 Consider this GHCi session:

 {{{
 Prelude> 1 / 2 / 2
 0.25
 Prelude> 1 / {-# SCC ann #-} 2 / 2
 1.0
 }}}

 Adding an SCC annotation changed the meaning of the expression.

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Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15730
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