[Bug libstdc++/47724] [C++0x] Regex string anchors cause segfault

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47724

--- Comment #6 from Jonathan Wakely <redi at gcc dot gnu.org> 2011-02-17 01:55:05 UTC ---
I've checked in a change which prevents the crash, but only by treating line
anchors as non-metacharacters.  Unfortunately our regex implementation is
incomplete, but this is better than crashing