https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117312
--- Comment #12 from Uroš Bizjak <ubizjak at gmail dot com> --- (In reply to Uroš Bizjak from comment #11) > (In reply to H. Peter Anvin from comment #9) > > So this sounds like it would solve additional problems, which may very well > > make it worthwhile. > > How about a guarantee that the first word of the redzone won't be used by > the compiler for anything else than short lived temporaries, so this > location can be clobbered at will? This guarantee would immediately solve > CALL instructions inside asm and PUSH/POP combos (e.g. flag intrinsics) Hm, while RED_ZONE_RESERVE would solve PUSH/POP combos, we don't know what called function will do with the stack. Effectively, in case of CALL inside asm, the callee function won't be leaf anymore, so "redzone" asm clobber would have to remove "leaf" status of the callee function.
