[GHC] #10383: AArch64: get GHC Calling convention working

[GHC]

#10383: AArch64: get GHC Calling convention working
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        Reporter:  erikd                |                   Owner:  erikd
            Type:  feature request      |                  Status:  new
        Priority:  normal               |               Milestone:  7.12.1
       Component:  Compiler             |                 Version:  7.11
      Resolution:                       |                Keywords:
Operating System:  Unknown/Multiple     |            Architecture:  aarch64
 Type of failure:  Building GHC failed  |               Test Case:
      Blocked By:                       |                Blocking:
 Related Tickets:                       |  Differential Revisions:
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Comment (by erikd):

 At @rwbarton's suggestion, compiled this program

 {{{
 main = print $ foldl (+) 0 [1..10000000]
 }}}

 with `ghc-stage1 -O0` (to thrash the GC) and the resulting program ran
 correctly. The problem does not seem to be GC related. Can also compile
 this program with

 {{{
 inplace/bin/ghc-stage1 -O0 -dynamic hello.hs -o hello
 }}}

 and that too runs fine so this is unlikely to be dynamic library loading.

 Running `inplace/bin/ghc-stage2 +RTS -Ds` results in:

 {{{
   7fb3bc9000: created capset 0 of type 2
   7fb3bc9000: created capset 1 of type 3
   7fb3bc9000: cap 0: initialised
   7fb3bc9000: assigned cap 0 to capset 0
   7fb3bc9000: assigned cap 0 to capset 1
   7fb3bc9000: allocated 1 more capabilities
   7fb3bc9000: new task (taskCount: 1)
   7fb3bc9000: returning; I want capability 0
   7fb3bc9000: resuming capability 0
   7fb3bc9000: cap 0: created thread 1
   7fb3bc9000: new bound thread (1)
   7fb3bc9000: cap 0: schedule()
   7fb3bc9000: cap 0: running thread 1 (ThreadRunGHC)
   7fb3bc9000: cap 0: created thread 2
   7fb3bc9000: cap 0: thread 1 stopped (yielding)
   7fb3bc9000: giving up capability 0
   7fb3bc9000: starting new worker on capability 0
   7fb3bc9000: new worker task (taskCount: 2)
   7fb39ff1f0: cap 0: schedule()
   7fb39ff1f0: cap 0: running thread 2 (ThreadRunGHC)
   7fb39ff1f0: cap 0: thread 2 stopped (yielding)
   7fb39ff1f0: giving up capability 0
   7fb39ff1f0: passing capability 0 to bound task 0x7fb3bc9000
   7fb3bc9000: woken up on capability 0
   7fb3bc9000: resuming capability 0
   7fb3bc9000: cap 0: running thread 1 (ThreadRunGHC)
 Segmentation fault (core dumped)
 }}}

 so the crash happens right after it switches threads.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10383#comment:10>
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