Comment (by David Radice):

I am not aware of any reason why THC should not work with a newer version of the ET: it should be only a matter of adding the thorns to the the standard ET thornlist. However, we have not tested it.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2315/issues-compiling-with-gcc73-with-c-17