[Bug testsuite/81399] New test case 27_io/basic_stringstream/assign/81338.cc fails on powerpc64le

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81399

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
FWIW it passes on gcc112 in the compile farm.