https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119708
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This change causes them to be rejected:
--- a/libstdc++-v3/include/bits/regex_scanner.h
+++ b/libstdc++-v3/include/bits/regex_scanner.h
@@ -161,7 +161,6 @@ namespace __detail
};
const std::pair<char, char> _M_ecma_escape_tbl[8] =
{
- {'0', '\0'},
{'b', '\b'},
{'f', '\f'},
{'n', '\n'},
Although the exception::what() strings leave a lot to be desired:
not valid: Back-reference referred to an opened sub-expression.
not valid: Back-reference index exceeds current sub-expression count.
