On Tue, Feb 26, 2013 at 8:01 AM, Eric Blake <eblake@xxxxxxxxxx> wrote: > On 02/25/2013 06:09 PM, Jeffrey Walton wrote: > >> GCC 4.8 added a couple of interesting flags >> (http://gcc.gnu.org/gcc-4.8/changes.html): -fsanitize=address and >> -fsanitize=thread. Some reading about them is available at >> http://llvm.org/devmtg/2012-11/Serebryany_TSan-MSan.pdf. >> >> It might be helpful to projects if the auto tools enabled one or both >> by default. The overhead on Address Sanitizer looks small compared to >> the payoff. > > That paper said address sanitizer added 2x slowdown (20x under > valgrind), and would need hardware support to cut the slowdown to only > 20%. It also said thread sanitizer added 20x to 300x slowdown. That > sounds like neither one should be enabled by default, but are best used > during development. But thanks for pointing them out - they sound > interesting. Yes, my bad. Address Sanitizer should be enabled for debug configurations by default (along with other "program diagnostics" to borrow from Posix). Release configurations should leave the choice to the user. Jeff _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx https://lists.gnu.org/mailman/listinfo/autoconf
