[GHC] #10149: The argument of mask does not always restore the masking state

[GHC]

#10149: The argument of mask does not always restore the masking state
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        Reporter:                    |                Owner:
  facundo.dominguez                  |  facundo.dominguez
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  libraries/base    |              Version:  7.11
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D1327
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"2b25a589ae8f6364bf086b4878f5ec26954931d3/ghc" 2b25a58/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="2b25a589ae8f6364bf086b4878f5ec26954931d3"
 base: Have the argument of mask restore the state.

 The implementation of `mask` and `uninterruptibleMask` assumed so far
 that the restore argument would be called in a context with the same
 masking state as that set by `mask` or `uninterruptibleMask`.

 This patch has the restore argument restore the masking, whatever the
 current masking state is.

 Test Plan: validate

 Reviewers: simonmar, hvr, austin, bgamari

 Reviewed By: bgamari

 Subscribers: thomie, qnikst

 Differential Revision: https://phabricator.haskell.org/D1327

 GHC Trac Issues: #10149
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10149#comment:6>
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