Hi Kim, Thanks for your review. I tried to solve the problem with your suggestion, and have just one question.
> On 29 September 2020 18:51 PM, Kim Barrett <kim.barr...@oracle.com> wrote: > I don't think using memory functions in place of string functions for string > manipulation is really an improvement. Yes, the original code has no problem basically but as you said asan seems incompatible with -Wstringop-truncation. Using 'memcpy' just a workaround. > I did a bit of experimenting. > > With gcc10.2, and using the --enable-asan configure option, we get a > -Wstringop-truncation warning in CompilerCounters::set_current_method, even > after careful adjustment of the code to use the documented idiom for > avoiding that warning. > > I initially wondered whether this might be only in fastdebug builds, where > we also define _FORTIFY_SOURCE=2. The asan faq > https://github.com/google/sanitizers/wiki/AddressSanitizer#faq > says asan doesn't work well with _FORTIFY_SOURCE. > > But the same warning occurs in a release build, where we aren't defining > _FORTIFY_SOURCE. > At this point all I can conclude is that --enable-asan (i.e. > -fsanitize=address) is simply incompatible with -Wstringop-truncation, at > least through gcc10. That seems like a bug that someone should report. > (Might be same as or related to > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85650) > > We don't normally build with -fsanitize=address; that's something that > someone might want to turn on sometimes for testing or debugging, but I > don't think we're planning to have it always on, even in debug builds. > Since it seems to be incompatible with various other options that we *do* > normally use, I think the way to allow --enable-asan to be (possibly) usable > is in the build system at configure time. That is, the --enable-asan > configure option should, in addition to adding -fsanitize=address, also (1) > disable -Wstringop-truncation and (2) disable the defining of > _FORTIFY_SOURCE in fastdebug builds. It looks like making those changes > involves conditionalizing their addition/removal using ${ASAN_ENABLED}. Disable -Wstringop-truncation seems more reasonable. Is that necessary to disable _FORTIFY_SOURCE in fastdebug? With gcc10.1, disable -Wstringop-truncation seems enough. I didn't test with fastdebug mode before, and now it has been tested in our internal both with release and fastdebug mode. Thanks, Eric
