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

[foom at fuhm dot net]

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

--- Comment #9 from James Y Knight <foom at fuhm dot net> ---
What good is having special code to allow linking compatibility, if the program
then can't work anyways? Isn't that anti-useful?

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

No, of course...I'm only a user....

> If you can provide a patch

I'm not certain, but it seems like probably the old-ABI
error_category::default_error_condition(int) ought to just return an
error_condition also with the old ABI, instead of the new one?


CC'ing debian's gcc maintainer, because the stated lack of desire for
compatibility between libstdc++ version 5, and g++ 4.9 seems like it's probably
something he wasn't aware of when upgrading.