[GHC] #12537: Parallel cabal builds Segmentation Fault on PowerPC 64-bit

[GHC]

#12537: Parallel cabal builds Segmentation Fault on PowerPC 64-bit
-------------------------------------+-------------------------------------
        Reporter:  michelmno         |                Owner:  trommler
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.0.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:  powerpc64
 Type of failure:  Incorrect result  |            Test Case:
  at runtime                         |
      Blocked By:  12469             |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D3984
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Changes (by trommler):

 * status:  new => patch
 * differential:   => Phab:D3984


Comment:

 Replying to [comment:11 trommler]:
 > I found an issue in the implementation of atomic read and atomic write
 operations in ghc-prim. I am working on a fix for powerpc64 and
 powerpc64le.
 Phab:3984 improves the situation a lot on an old PowerMac the segfault
 occurs only on every other run where before this patch I would see a
 segfault on almost all build attempts.

 The correctness issue I found in `libraries/ghc-prim/cbits/atomic.c`
 affects all platforms that are using the fallback functions
 `hs_atomicread*` and `hs_atomicwrite`. I will create a separate ticket for
 that.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12537#comment:12>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler