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SubjectRe: Is clobber "memory" in include/asm-i386/system.h necessary?
Date
> So what's up with these clobbers?  If they aren't necessary, they
> should be removed because they have a detrimental effect on code
> generation. If they are necessary, how about a comment explaining
> why?

To force a cli/sti to act as a store/load barrier. That saves all the variables
in the interrupt code being volatile and making gcc generate diabolically
bad code.

Alan



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