https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64467
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- Almost certainly r217066. Is this a newlib target? I would expect to see the same failure for all newlib targets, as I defined std::ctype_base::blank to be equal to std::ctype_base::space for newlib (and any libc where I couldn't determine the right bitmask for the [:blank:] character class) and the [:space:] class includes newline.
