[Bug target/94087] std::random_device often fails when used from multiple threads

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94087

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Version|9.2.1                       |10.1.0
   Target Milestone|---                         |10.2

--- Comment #23 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #22)
> We could fit a linear_congruential_engine in the unused space of the union.

But we'd still need to seed it on construction, even if we never use it.

Changing version to 10 since there's no bug in gcc 9 (comment 16 explains why
it was seen there).