[Bug c++/34331] New: __attribute((externally_visible))) should work on class declaration

["bruce_pedersen at altera dot com" <gcc-bugzilla at gcc dot gnu dot org>]

When applied to a class declaration, "__attribute((externally_visible))" should
act as if it were applied to each function or data member in the class -- just
like '__attribute((visibility("protected")))' works in GCC4.2.1.  This would
allow using the "-fwhole-program -fvisibility=hidden" optimizations when
creating C++ shared-object files. In particular, one should be able to do:
#define DLLEXPORT __attribute(externally_visible,visibility("protected")))
#define DLLIMPORT __attribute(externally_visible,visibility("default")))
class DLLEXPORT FOO {
  FOO();
  void foo_func(); 
  ..etc.
};
In GCC4.2.1, the above code will issue a warning, ignore the
"externally_visible" attribute, and the above class functions will not be
exported (and possibly not even implemented) in the *.so file when
-fwhole-program is used.
The arguments for allowing the "externally_visible" attribute on the class
declaration (as opposed to forcing users to put in on every class member) are
the same as those for allowing the "visibility" attribute there as well: ease
of use and syntax-compatibility with other major compilers.


-- 
           Summary: __attribute((externally_visible))) should work on class
                    declaration
           Product: gcc
           Version: 4.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bruce_pedersen at altera dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34331