https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77728
--- Comment #20 from Jakub Jelinek <jakub at gcc dot gnu.org> --- BTW, the wording e.g. i386 backend has is: inform (input_location, "the ABI of passing structure with complex float" " member has changed in GCC 4.4"); In this arm/aarch64 case, the wording can't be as specific, because it isn't all arguments of this type, but only some arguments of certain type (at some positions; for some types like those that have more aligned static data members it is all such positioned arguments, for others, e.g. the templates where the alignment used to depend on instantiation vs. non-instantiation something earlier, only some), but you should consider using inform rather than warning for consistency, and you should mention the GCC version where it has changed and maybe also print the type in the diagnostic, so that user at least knows what type it is that is problematic (but as it is not something as simple as in the i386 case, there should not be a single inform per TU, but about each case this is encountered). Richard said we should defer RC1 till this is done, do you think you can have a patch for both architectures written today, tested over the weekend, so that we could do RC1 on Monday or Tuesday at latest? Is there an agreement in ARM that what the patch does (for aarch64, and similar one for arm) is what the AAPCS says?