[GHC] #9878: Static pointers in GHCi cause panic

[GHC]

#9878: Static pointers in GHCi cause panic
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              Reporter:  monoidal    |            Owner:  facundo.dominguez
                  Type:  bug         |           Status:  new
              Priority:  normal      |        Milestone:
             Component:  Compiler    |          Version:  7.9
            Resolution:              |         Keywords:
      Operating System:              |     Architecture:  Unknown/Multiple
  Unknown/Multiple                   |       Difficulty:  Unknown
       Type of failure:  GHCi crash  |       Blocked By:
             Test Case:              |  Related Tickets:
              Blocking:              |
Differential Revisions:              |
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Comment (by mboes):

 > Then we need to decide what to do with the SPT implementation. To make
 it thread-safe we can use a readers-writer lock implemented with mutexes,
 or maybe someone can suggest a better alternative.

 -XStaticPointers is limited to the following use case: the universe of
 static forms that exist in the program is fixed at compile time and
 constant throughout the lifetime of the program. Using the `static`
 keyword inside GHCi does not fit this assumption, nor does dynamic
 (runtime) code linking. So the more pressing question is, in the original
 intended use case, are there ever concurrent updates to the SPT? That is,
 does module initialization happen concurrently at runtime? If not, then
 let's keep it simple...

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9878#comment:14>
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