- Segher needs to review which attributes globvars needs to not be
optimized away.
It doesn't need any: if it's used, it won't be optimised away; and if it isn't used, who cares :-)
There could be an issue if you hid some facts from the compiler, but you didn't.
The only remaining issue is, does that struct actually get allocated on the stack (and not in .data or similar)? There is no way to force this AFAIK: C doesn't even know what a stack is, and there is no GCC extension for this. But don't worry too much about this, every compiler we use does in fact put this on the stack.
Segher