[GHC] #1: Implicit parameters cause strange behavi

[GHC]

#1: Implicit parameters cause strange behavi
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       Reporter:  nobody        |      Owner:  nobody
           Type:  bug           |     Status:  closed
       Priority:  normal        |  Milestone:
      Component:  Compiler      |    Version:  5.0
     Resolution:  Fixed         |   Keywords:
Type of failure:  None/Unknown  |
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Comment (by Ben Gamari <ben@…>):

 In [changeset:"e29b1ee72d77d5a06ac949f9dcc80108243a25c0/ghc"
 e29b1ee7/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="e29b1ee72d77d5a06ac949f9dcc80108243a25c0"
 Add a RTS option -xp to load PIC object anywhere in address space

 Summary:
 This re-applies {D5195} with fixes for i386:
 * Fix unused label warnings, see {D5230} or {D5273}
 * Fix a silly bug introduced by moving `#if`

 {P190}

 Add a RTS option -xp to load PIC object anywhere in address space. We do
 this by relaxing the requirement of <0x80000000 result of
 `mmapForLinker` and implying USE_CONTIGUOUS_MMAP.

 We also need to change calls to `ocInit` and `ocGetNames` to avoid
 dangling pointers when the address of `oc->image` is changed by
 `ocAllocateSymbolExtra`.

 Test Plan:
 See {D5195}, also test under i386:

 ```
 $ uname -a
 Linux watashi-arch32 4.18.5-arch1-1.0-ARCH #1 SMP PREEMPT Tue Aug 28
 20:45:30 CEST 2018 i686 GNU/Linux
 $ cd testsuite/tests/th/ && make test
 ...
 ```

 will run `./validate` on stacked diff.

 Reviewers: simonmar, bgamari, alpmestan, trommler, hvr, erikd

 Reviewed By: simonmar

 Subscribers: rwbarton, carter

 Differential Revision: https://phabricator.haskell.org/D5289
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1#comment:9>
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