[Bug libstdc++/66438] libstdc++ 5.1 broke binary compat with old code using std::error_category

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66438

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to James Y Knight from comment #5)
> The *one and only purpose* of the file
> libstdc++-v3/src/c++11/compatibility-c++0x.cc is to provide binary
> compatibility for c++11 binaries compiled against older libstdc++ versions,
> and now running against a newer one.

It ensures they will still link.

> If libstdc++.so.6, version 5.1, is not supposed to work properly with c++
> binaries compiled by the 4.9 compiler, it should not be providing these
> compatibility symbols at all.

I would prefer that, but it's not our policy.

> Since it does provide them, there is clearly intent to provide compatibility

I didn't realise you were the maintainer and knew what's supposed to work.

Oh wait, you're not :-)