[Bug libstdc++/82346] [5.5 Regression] String is not detected as a part of std

[krzysio.kurek at wp dot pl]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82346

--- Comment #8 from krzysio.kurek at wp dot pl ---
Wouldn't this bug affect all gcc compilers? I have 5, 6 and 7 installed, and
only 5 is affected.