[GHC] #16107: Update GCC compiler & friends

[GHC]

#16107: Update GCC compiler & friends
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        Reporter:  flip101           |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  8.10.1
       Component:  Compiler          |              Version:  8.6.3
      Resolution:                    |             Keywords:
Operating System:  Windows           |         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 Phyx-):

 I've intentionally not updated them because mingw-w64 have not been able
 to release the 32-bit version of the toolchain due to a stage3 failure for
 GCC 8 and now 9.

 Originally no GCC 8 builds were available, I fixed this with upstream and
 the 64-bits were released but the 32-bit ones are still failing
 https://gcc.gnu.org/ml/gcc/2019-01/msg00178.html which is what I'm working
 on with upstream now.

 The problem is I don't particularly want a different toolchain and runtime
 for the 32-bit and 64-bit toolchains as it'll be confusing for the users
 but also we don't test the 32-bit ones often, so we'll likely to break it
 with a different toolchain.

 If we want to update before the tarballs are released by mingw-w64 we'll
 have to spin our own binaries disabling the ada bootstrap.

 the CRT I haven't updated due to a weird behavior with NaN and INF in a
 testcase, though that may have been fixed now. Haven't checked yet.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16107#comment:2>
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