[GHC] #8834: 64-bit windows cabal.exe segfaults in GC

[GHC]

#8834: 64-bit windows cabal.exe segfaults in GC
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        Reporter:  awson          |            Owner:
            Type:  bug            |           Status:  patch
        Priority:  highest        |        Milestone:  7.8.1
       Component:  Compiler       |          Version:  7.8.1-rc2
      Resolution:                 |         Keywords:
Operating System:  Windows        |     Architecture:  x86_64 (amd64)
 Type of failure:  Runtime crash  |       Difficulty:  Unknown
       Test Case:                 |       Blocked By:
        Blocking:                 |  Related Tickets:
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Comment (by awson):

 All looks quite the contrary:
 {{{
 ...
 #define REG_R2    r14
 #define REG_R3    rsi
 #define REG_R4    rdi
 ...
 }}}

 [http://msdn.microsoft.com/en-us/library/6t169e9c.aspx The registers RBX,
 RBP, RDI, RSI, RSP, R12, R13, R14, and R15 are considered nonvolatile...]

 And we have *not defined* here:
 {{{
 #if !defined(mingw32_HOST_OS)
 #define CALLER_SAVES_R3
 #define CALLER_SAVES_R4
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8834#comment:37>
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