[GHC] #7684: cgrun071 segfaults

[GHC]

#7684: cgrun071 segfaults
----------------------------------+----------------------------------
        Reporter:  tibbe          |            Owner:  leroux
            Type:  bug            |           Status:  new
        Priority:  normal         |        Milestone:  7.8.1
       Component:  Compiler       |          Version:  7.7
      Resolution:                 |         Keywords:
Operating System:  MacOS X        |     Architecture:  x86_64 (amd64)
 Type of failure:  Runtime crash  |       Difficulty:  Unknown
       Test Case:  cgrun071       |       Blocked By:
        Blocking:                 |  Related Tickets:
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Comment (by leroux):

 attachment:cgrun071-rts-asm-diffs.txt

 Both cgrun071 binaries are built, dumped, and diff'd as follows.
 {{{
 $ ghc-stage2 -fforce-recomp -dcore-lint -dcmm-lint -dno-debug-output -no-
 user-package-db -rtsopts -ddump-to-file -ddump-asm -fno-ghci-history -o
 cgrun071 cgrun071.hs -O -fasm # TEST=cgrun071 WAY=normal EXTRA_HC_OPTS
 ="-ddump-to-file -ddump-asm"
 $ tool -tV cgrun071 > cgrun071.S # dump the object code
 }}}

 And then simply
 {{{
 $ diff -y cgrun071-gcc48-passed.S cgrun071-gcc42-failed.S
 }}}

 The left side of the diff is from ghc (built with gcc48, passed) and the
 right is built with gcc42 (failed, segfault).

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7684#comment:25>
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