[GHC] #14244: ghc-prim: hs_atomicread* and hs_atomicwrite* missing barriers

[GHC]

#14244: ghc-prim: hs_atomicread* and hs_atomicwrite* missing barriers
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        Reporter:  trommler          |                Owner:  trommler
            Type:  bug               |               Status:  patch
        Priority:  high              |            Milestone:  8.4.1
       Component:  Prelude           |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #12537            |  Differential Rev(s):  Phab:D4009
       Wiki Page:                    |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"59de290928e6903337f31c1f8107ac8a98ea145d/ghc"
 59de2909/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="59de290928e6903337f31c1f8107ac8a98ea145d"
 Update autoconf test for gcc to require 4.7 and up

 Fixing #14244 required the newer gcc atomic built-ins that are provided
 from 4.7 and up. This updates the test to check for minimum gcc version
 4.7.

 The version tests for 3.4 (!), 4.4, and 4.6 are no longer needed and can
 be removed. This makes the build system simpler.

 Test Plan: validate

 Reviewers: austin, bgamari, hvr, simonmar

 Reviewed By: bgamari

 Subscribers: rwbarton, thomie, erikd

 Differential Revision: https://phabricator.haskell.org/D4165
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14244#comment:5>
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