Hi Mark, > Why can't you simply use the configure support?
I can't interfere with CFLAGS/CXXFLAGS passed by OSS-Fuzz. For example if I used `--enable-sanitize-undefined` I would overwrite all the `-fsanitize=...` and `-fno-sanitize-recover=...` flags used by OSS-Fuzz. I also embed elfutils into the libbpf builds there so if I relied on the configure script I would effectively instrument libbpf and elfutils differently because libbpf would still be built with the original CFLAGS. Generally OSS-Fuzz doesn't expect its CFLAGS/CXXFLAGS to be changed in any way by build systems. When they collide stuff just stops working sometimes. The latest example would be https://github.com/google/oss-fuzz/pull/9427#issuecomment-1384195091 (where meson collided with OSS-Fuzz and systemd, lxc and dbus-broker just failed to compile). > Also I think there is simply a bug in clang that it doesn't link > properly with libasan/ubsan when -fsanitize=address/undefined is given. I think it's always been this way and it's unlikely to ever be fixed. Issues like https://bugs.llvm.org/show_bug.cgi?id=30333 have been open for years and for example meson just gave up and started printing warnings in https://github.com/mesonbuild/meson/commit/bde99eb6c40a9c7bc4055b0dc84a31021b7623d2 to make it clear that it isn't responsible for making clang, ASan and --no-undefined,z,defs work. > If you could add a configure check for that bug then we could add the > no no-undefined trick independent of compiler used. I'll try to figure out how it can be done. Apart from OSS-Fuzz (which I think is a corner case in a way) It should hopefully make `--enable-sanitize-*` work with clang. Thanks, Evgeny Vereshchagin
