https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61771
--- Comment #3 from Evgeniy Stepanov <eugeni.stepanov at gmail dot com> --- Yes, FP on ARM is non-standard and differs in GCC and Clang implementations. Disabling fast unwind is not really an option, as you are looking at 10x, maybe 100x slowdown (depending of the app, of course). It should be possible to detect fp layout on the frame basis - there is a slot (don't know which one off the top of my head) that is FP in one compiler and return address in the other. Comparing its contents with the current stack limits (readily available in ASan) should do the trick. Of course, it would be awesome if we could synchronize (and document somewhere) FP stack layout between GCC and Clang - after all, there is no strong reason to do it one way or the other.
