[Bug testsuite/63332] problem with VERIFY in ext/random/k_distribution/operators/serialize.cc execution test

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63332

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Yes, there must be some difference that isn't visible in the serialized output,
which would imply the values fail to do a proper round trip, so we're not
writing them with enough precision.

Maybe we should use hexfloat output for serializing distributions, not decimal.