https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96503
--- Comment #7 from Martin Uecker <muecker at gwdg dot de> --- Am Mittwoch, dem 25.10.2023 um 11:08 +0000 schrieb siddhesh at gcc dot gnu.org: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96503 > > --- Comment #6 from Siddhesh Poyarekar <siddhesh at gcc dot gnu.org> --- > So basically, > > __builtin_with_access(void *ptr, size_t size, int access) > > where access == > > -1: Unknown access semantics > 0: none > 1: read_only > 2: write_only > 3: read_write > > should address both access and alloc_size and even counted_by. Yes, sounds good. > We would need > to emit the builtin in the caller as well as callee of the function that has > the access attribute while for alloc_size, we only need to emit this in the > caller. Yes, makes sense, although I guess caller part for "access" is only for warning and not relevant for BDOS, so could potentially stay as it is for now. For __builtin_with_access we probably only want to allow reducing the object size, while the 'extend_size' workaround used by systemd (cf comment #4) would need to extend it. Maybe we need another flag? Martin
