On Tue, 10 Jun 2014, Jiri Kosina wrote: > We have been chasing a memory corruption bug, which turned out to be > caused by very old gcc (4.3.4), which happily turned conditional load into > a non-conditional one, and that broke correctness (the condition was met > only if lock was held) and corrupted memory. > > This particular problem with that particular code did not happen when > never gccs were used. I've brought this up with our gcc folks, as I wanted > to make sure that this can't really happen again, and it turns out it > actually can.
For the record (and for mailinglist archives to catch this information) -- the default has been changed for gcc 4.10 to a sane value (0). I'd however suggest we keep changes made by commit 69102311a ("./Makefile: tell gcc optimizer to never introduce new data races") for rather a long time. -- Jiri Kosina SUSE Labs