[GHC] #15268: Clarify and test the interaction of -with-rtsopts and -rtsopts flags

[GHC]

#15268: Clarify and test the interaction of -with-rtsopts and -rtsopts flags
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        Reporter:  osa1              |                Owner:  (none)
            Type:  task              |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by AndreasK):

 Replying to [ticket:15268 osa1]:
 > I'd expect `-with-rtsopts` to work even with `-rtsopts=ignoreAll`, but I
 don't know if this is really the case.

 This is how it's intended if not it would be a bug.

 > and because we don't have a way to print RTS flags (see #15261 for this)
 it's hard to make sure this works as expected.

 You can test this works by setting an RTS flags and read it from Haskell.
 For example set the number of generations and print them from haskell.

 {{{
 import GHC.RTS.Flags (getGCFlags, generations)

 main :: IO ()
 main = do
     gcFlags <- getGCFlags
     putStr . show $ generations gcFlags
 }}}

 This is already done in the testsuite by T12870h.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15268#comment:1>
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