Re: [Bug-readline] [PATCH] Enable visibility annotations

[Pedro Alves <palves@redhat.com>]

On 04/20/2016 10:45 AM, Yury Gribov wrote:
> On 04/20/2016 12:22 PM, Pedro Alves wrote:

>> - Claim that the symbols may no longer be available in a
>>    future release.
> 
> You mean just email respective package maintainers?

I was thinking readline's CHANGES / release notes.

Emailing respective package maintainers / filing bugs with them
doesn't hurt of course.

> 
>> - Give time for packages to clean themselves up, and propose
>>    any necessary new replacement APIs.
> 
> This would require significant expertise in readline though...

The alternative is bless the private symbols as
public API forever...  Each package owner will know what their
package needs from readline and why they found a need
to (ab)use readline private symbols.  I see no way around that.

> 
>> - Optionally, in the release after the next, mark the symbols
>>    as deprecated with __attribute__((deprecated)), so packages
>>    that abuse private symbols get a build-time warning.
> 
> That won't help as these symbols are not present in headers anyway.  All
> users have their own private declarations.

OK.  Making it a linker warning instead,using ".gnu.warning.SYMBOL"
sections might still work:

 http://www.airs.com/blog/archives/54

Not sure it's a good idea to raise warnings without alternatives
already in place though, thus my "Optionally".

Thanks,
Pedro Alves