[GHC] #13440: putStr doesn't have the same behavior in GHCi and after compilation with GHC

17 Mar 2017

      #13440: putStr doesn't have the same behavior in GHCi and after compilation with
GHC
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           Reporter:  vanto          |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.2
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Other
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 Hi,

 {{{
 main :: IO ()
 main = do {
              putStr "hello";
              x <- getChar; -- or x <- getLine;
              putStr "x = ";
              print x;
            }
 }}}
 the program works in GHCi and after compilation with GHC.
 in GHCi it works fine but after compilation it does not work fine.
 in GHCi the first line of code is evaluated the first while after
 compilation
 is the second line which is evaluated first.
 so in GHCi we have as a result:

 {{{
 hellom
 x = 'm'
 }}}

 and after compilation we have as a result:

 {{{
 m
 hellox = 'm'
 }}}
 After compilation, putStr is not evaluated the first. It is getChar or
 getLine.
 In GHCi the behavior is correct. But after compilation the behavior is
 strange.

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13440
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