hyc@symas.com wrote:

I suspect this is a bug in glibc mcheck's pthread support, since ElectricFence with EF_PROTECT_BELOW set will detect 100% of all memory underruns, and no such error occurs there.

Also this report (which it seems the original is no longer accessible) implies the same problem with mcheck

http://www.google.com/search?q=cache:dAqJIBQSNRQJ:groups.google.com/group/gn...

Eh... Looking at glibc's mcheck code http://sourceware.org/cgi-bin/cvsweb.cgi/libc/malloc/?cvsroot=glibc shows that it has no mutex protection at all. It is completely invalid here, this ITS will be closed.