2018-09-21  François Dumont  <fdumont@gcc.gnu.org>

	PR libstdc++/87135
	* src/c++11/hashtable_c++0x.cc (_Prime_rehash_policy::_M_next_bkt):
	Use __builtin_floor to compute _M_next_resize.
	* testsuite/23_containers/unordered_set/hash_policy/71181.cc: Adapt.
	* testsuite/23_containers/unordered_set/hash_policy/prime_rehash.cc:
	Adapt.

From-SVN: r264494