[Boost-bugs] [Boost C++ Libraries] #7095: warning: unrecognized __attribute__((__may_alias__))

Subject: [Boost-bugs] [Boost C++ Libraries] #7095: warning: unrecognized __attribute__((__may_alias__))
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-07-06 09:47:20

#7095: warning: unrecognized __attribute__((__may_alias__))
--------------------------------+-------------------------------------------
 Reporter:  1czajnik@…          |       Owner:  igaztanaga
     Type:  Bugs                |      Status:  new       
Milestone:  To Be Determined    |   Component:  move      
  Version:  Boost 1.50.0        |    Severity:  Problem   
 Keywords:                      |  
--------------------------------+-------------------------------------------
 Hello,

 boost/move.hpp contains:
 {{{
 //Move emulation rv breaks standard aliasing rules so add workarounds for
 some compilers
 #ifdef __GNUC__
    #define BOOST_MOVE_ATTRIBUTE_MAY_ALIAS __attribute__((__may_alias__))
 #else
    #define BOOST_MOVE_ATTRIBUTE_MAY_ALIAS
 #endif
 }}}
 and using {{{__attribute__((__may_alias__))}}} causes a warning on my TI
 compiler.

 Would a fix by guarding against {{{__GNUC__>=4}}} be welcome, or are there
 some {{{__GNUC__=3}}} compilers, that need this pragma to be enabled?

 {{{
 Index: move.hpp
 ===================================================================
 --- move.hpp    (revision 0)
 +++ move.hpp    (revision 1)
 @@ -217,7 +217,7 @@
  #if defined(BOOST_NO_RVALUE_REFERENCES) &&
 !defined(BOOST_MOVE_DOXYGEN_INVOKED)

     //Move emulation rv breaks standard aliasing rules so add workarounds
 for some compilers
 -   #ifdef __GNUC__
 +   #if defined(__GNUC__) && (__GNUC__ >= 4)
        #define BOOST_MOVE_ATTRIBUTE_MAY_ALIAS
 __attribute__((__may_alias__))
     #else
        #define BOOST_MOVE_ATTRIBUTE_MAY_ALIAS
 }}}

 Regards,
 Kris

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7095>
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