[GHC] #12572: `readdir_r` is deprecated

[GHC]

#12572: `readdir_r` is deprecated
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        Reporter:  erikd             |                Owner:  erikd
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Core Libraries    |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Building GHC      |  Unknown/Multiple
  failed                             |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by ezyang):

 When I validate GHC with the latest version of unix, I get a segfault.

 {{{
 *** Error in `/home/hs01/ezyang/ghc-validate/inplace/lib/bin/haddock':
 free(): invalid pointer:
  0x00000000022f18e0 ***
 ======= Backtrace: =========
 /usr/lib/libc.so.6(+0x70c4b)[0x7f0860463c4b]
 /usr/lib/libc.so.6(+0x76fe6)[0x7f0860469fe6]
 /usr/lib/libc.so.6(+0x777de)[0x7f086046a7de]
 /home/hs01/ezyang/ghc-validate/libraries/unix/dist-
 install/build/libHSunix-2.7.2.0-ghc8.1.20160
 905.so(__hscore_free_dirent+0x9)[0x7f0863212010]
 /home/hs01/ezyang/ghc-validate/libraries/unix/dist-
 install/build/libHSunix-2.7.2.0-ghc8.1.20160
 905.so(+0x97197)[0x7f08631d5197]
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12572#comment:6>
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