Comment 28 for bug 852760

(In reply to comment #7)
> -fno-builtin-strlen, but you really don't want to use that, it will penalize
> code way too much (then even strlen ("abc") isn't folded etc.).

Thanks. Any chance to get back the 'repnz scasb'-based implementation that -O1 produces?

> Just live with valgrind false positives, any time it reports a read access
> with size N as M bytes inside a block of size O alloc'd
> where (M % N) == 0 && M == (O & ~(N - 1)) && O > M it is suspect you might be
> looking at a valgrind false positive.

That's something hard to distinguish from the regular off-by-one errors occurring in C code as long as the unrolled strlen() does not appear on the backtrace.