[GHC] #4822: build failures on ARM linux with gcc4.5

[GHC]

#4822: build failures on ARM linux with gcc4.5
---------------------------------+------------------------------------------
    Reporter:  jani@…            |       Owner:              
        Type:  bug               |      Status:  new         
    Priority:  normal            |   Component:  Compiler    
     Version:  6.12.1            |    Keywords:              
    Testcase:                    |   Blockedby:              
          Os:  Unknown/Multiple  |    Blocking:              
Architecture:  Unknown/Multiple  |     Failure:  None/Unknown
---------------------------------+------------------------------------------
 On Ubuntu, since switching to gcc4.5 ARM builds fail when linking.
 Here's an instance of a failure (look for 'Invalid')
 http://launchpadlibrarian.net/58068323/buildlog_ubuntu-natty-armel
 .haskell-filestore_0.3.4.2-1_FAILEDTOBUILD.txt.gz

 the ghc unix .a file refers to sem_post which is in pthread.

 Adding -lpthread at the end of the generated gcc command line makes it
 work, and the resulting executable is linked to pthread.
 On x86 lpthread may come in anyway because of slightly different symbols
 in the linked DSOs.

 -no-add-needed is the flag that is newly passed by gcc 4.5 (I am not sure
 if by default or an Ubuntu setting) but it causes only libs that are
 directly linked to end up in the final executable.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4822>
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