https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113293
--- Comment #4 from KBDeveloper <dories.spirits_0p at icloud dot com> --- (In reply to Alexander Monakov from comment #3) > (In reply to KBDeveloper from comment #2) > > > > Ah, that makes sense. I had assumed that taking the address of arg would > > force gcc to store it in memory somewhere. > > Is there a reason why gcc then allocates 8 bytes on the stack and fills r1 > > with sp - #7? Or is what I had just UB and gcc can do whatever? > > The compiler allocates stack memory for 'arg' and passes the address of > 'arg' to the asm; it is necessary in case the asm does something with it > without reading 'arg' itself. One example would be installing a hardware > watchpoint on that memory location. That makes sense. Thanks for the explanation (and your time!)
