On 09.10.2012 21:47, Eitan Adler wrote: > On 9 October 2012 12:33, Andrey Chernov <a...@freebsd.org> wrote: >> Do you check assembler output for _both_ cases? > > Yes. ... > http://blog.eitanadler.com/2012/10/reduced-entropy-in-rand-and-random.html
At this URL I see only already known buggy assembler without 'volatile' keyword (which is fixed by adding 'volatile' in srandomdev()). As I already mention, adding 'volatile' helps any gcc and clang finally generated assembler code (checked by cc -S ...). What happens with LLVM intermediate code, I mean mentioned by David call void @srand(i32 undef) is a big question and perhaps clang bug. Please note that we use 'volatile' a lot in the kernel, just 'grep -r volatile /sys'. Some of that potentially can hit the same (probably) bug. And, in case it is the bug, it should be fixed in clang. > volatile is still undefined: see 5.1.2.2.3 and 6.7.2.4 of ISO9899 I don't have ISO9899 nearby, could you directly quote mentioned sections, please? Do you against 'volatile' usage at all? It seems whole kernel (see above) contradicts with such point of view. _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
