[libstdc++/66359] Backport change 217461 to 4.9 branch?

[Tim Shen]

(I noticed the archive didn't associate
https://gcc.gnu.org/ml/libstdc++/2015-06/msg00008.html with previous
messages, so I'm posting a new one)

Hi,

Half a year ago I made this change:
https://gcc.gnu.org/viewcvs/gcc?view=revision&revision=217461

Discussion is here: https://gcc.gnu.org/ml/libstdc++/2014-11/msg00045.html

I did asked about backporting this to 4.9 and then forgot about it :)

Is this backport compatible and worth doing (base on my knowledge, yes)?

Thanks!


-- 
Regards,
Tim Shen