[Bug libstdc++/86977] [g++ 8.1.0-5ubuntu1~14.04] error: static assertion failed: unordered container must have the same value_type as its allocator

[joao at neto dot pt]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86977

--- Comment #2 from João Neto <joao at neto dot pt> ---
Hi Jonathan! Thanks for the quick reply!

Two follow-up questions:

(1) Shouldn't it be also flagged as an error in `gcc-6` and `gcc-7` with
`-std=c++17`?

(2) How can I reliably find the node-type allocated by the map if I'd want to
use `-std=c++17`? Isn't it implementation-defined?

https://stackoverflow.com/questions/49736817/stdunordered-map-with-boostinterprocess-allocator-in-shared-memory-drawbac/49738871#49738871