https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109098
--- Comment #6 from joseph at codesourcery dot com <joseph at codesourcery dot com> --- For diagnosis of non-UTF-8 in strings / comments, see commit 0b8c57ed40f19086e30ce54faec3222ac21cc0df, "libcpp: Add -Winvalid-utf8 warning [PR106655]" (implementing a new C++ requirement).
