[GHC] #5129: "evaluate" optimized away

[GHC]

#5129: "evaluate" optimized away
-------------------------------------+-------------------------------------
        Reporter:  dons              |                Owner:  simonmar
            Type:  bug               |               Status:  closed
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  7.0.3
      Resolution:  fixed             |             Keywords:  seq, evaluate
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D615
       Wiki Page:                    |
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Comment (by alpmestan):

 A recent `./validate --slow` run I did revealed that this test doesn't
 pass anymore. I found out that something changed between `8.0.2` and
 `8.2.1`:

 {{{#!sh
 $ nix-shell -p haskell.compiler.ghc821 --run 'ghc-8.2.1 -O -fforce-recomp
 ~/ghc/testsuite/tests/codeGen/should_run/T5129.hs &&
 /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129'
   [1 of 1] Compiling Main             (
 /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129.hs,
 /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129.o )
 Linking /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129 ...
 T5129: HUnitFailure "must throw when given a negative number"

 $ nix-shell -p haskell.compiler.ghc802 --run 'ghc-8.0.2 -O -fforce-recomp
 ~/ghc/testsuite/tests/codeGen/should_run/T5129.hs &&
 /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129'
 [1 of 1] Compiling Main             (
 /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129.hs,
 /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129.o )
 Linking /home/alp/ghc/testsuite/tests/codeGen/should_run/T5129 ...

 $
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5129#comment:20>
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