[FFmpeg-devel] Visibility implementation

[Måns Rullgård]

Diego Biurrun <diego at biurrun.de> writes:

> On Sat, Oct 18, 2008 at 11:57:17AM +0100, M?ns Rullg?rd wrote:
>> Diego Biurrun <diego at biurrun.de> writes:
>> 
>> > On Thu, Jul 31, 2008 at 08:03:50PM +0300, Uoti Urpala wrote:
>> >> On Wed, 2008-07-30 at 05:45 +0300, Uoti Urpala wrote:
>> >> > The attached patch adds visibility information for lots of symbols in
>> >> 
>> >> I created a new version that adds visibility information for most
>> >> libavcodec symbols. This time I split the patch into two parts. The
>> >> first one has the repeated changes per internal header marking them as
>> >> such. The second adds visibility information for some of the symbols
>> >> that are not static but not declared in any header either, adds
>> >> exceptions for some symbols which are declared in libavcodec headers but
>> >> used outside it (mainly in libavformat), and defines the macros used.
>> >
>> > Here is a new version of those patches, updated for HEAD.  Uoti, maybe
>> > you can doublecheck nothing is missing...
>> >
>> > --- a/libavutil/internal.h
>> > +++ b/libavutil/internal.h
>> > @@ -50,6 +50,12 @@
>> >  
>> > +#define START_HIDDEN_VISIBILITY_SECTION _Pragma("GCC visibility push(hidden)")
>> > +#define END_VISIBILITY_SECTION          _Pragma("GCC visibility pop")
>> > +
>> > +#define HIDDEN             __attribute__((visibility("hidden")))
>> > +#define EXTERNALLY_VISIBLE __attribute__((visibility("default")))
>> 
>> These should be under appropriate ifdefs.  The names are awfully long
>> too.
>
> START_HIDDEN_VISIBILITY
> END_HIDDEN_VISIBILITY

What about this:

+#define START_HIDDEN _Pragma("GCC visibility push(hidden)")
+#define END_HIDDEN   _Pragma("GCC visibility pop")
+
+#define HIDDEN  __attribute__((visibility("hidden")))
+#define VISIBLE __attribute__((visibility("default")))

Just because a feature was designed to work around C++ bloat, we don't
have to adopt their bloated naming style when we use it.

-- 
M?ns Rullg?rd
mans at mansr.com