Bug#1030775: xtensor: baseline violation: builds with -march=native

[Drew Parsons]

Source: xtensor
Followup-For: Bug #1030775
Control: tags -1 wontfix moreinfo

I think this is not a bug.  xtensor is a header-only library. The
builds you're seeing with -march=native are in the tests only, not
compiled into the binary package.

We could make some effort to prevent the tests running with
-march=native. But I prefer to leave the flag there for tests, since
it better reflects how the package might be used by an end-user.

I think we can close this bug, but I'll leave it open for a little
while in case further discussion is needed.