gcc should allow to apply the visibility attribute to classes and other complex
types. It should behave as if the visibility attribute was specified on each member
function and variable, unless one of them "overwrites" the setting by specifying a custom
visibility. 

This feature is necessary to easily control the amount of exported symbols in bigger
C/C++ projects.

Release:
3.3

Environment:
System: Linux matrix 2.4.19-4GB #1 Thu Nov 14 09:55:36 UTC 2002 i686 unknown
Architecture: i686

host: i486-suse-linux-gnu
build: i486-suse-linux-gnu
target: i486-suse-linux-gnu
configured with: ../configure --enable-threads=posix --prefix=/usr --with-local-prefix=/usr/local --infodir=/usr/share/info --mandir=/usr/share/man --libdir=/usr/lib --enable-languages=c,c++,f77,objc,java,ada --enable-libgcj --with-gxx-include-dir=/usr/include/g++ --with-slibdir=/lib --with-system-zlib --enable-shared --enable-__cxa_atexit i486-suse-linux

How-To-Repeat:

try to compile this example file: 

#include <stdio.h>

class __attribute__( ( visibility( "hidden" ) ) ) MyClass
{
public:
    MyClass();

    static int member;
};

int MyClass::member;

MyClass::MyClass()
{ }

int main()
{
    MyClass f;
    printf( "%d",MyClass::member );
    return 0;
}

#g++ -Wall test.cc
test.cc:9: warning: `visibility' attribute does not apply to types