On Thu, Jun 06, 2019 at 03:58:17AM -0700, Paul E. McKenney wrote: > > I cannot immediately think of a way that the compiler could get this > wrong even in theory, but similar code sequences can be messed up. > The reason for this is that in theory, the compiler could use the > stored-to location as temporary storage, like this: > > a = whatever; // Compiler uses "a" as a temporary > do_something(); > whatever = a; > a = 1; // Intended store
Well if the compiler is going to do this then surely it would continue to do this even if you used WRITE_ONCE. Remember a is not volatile, only the access of a through WRITE_ONCE is volatile. Cheers, -- Email: Herbert Xu <herb...@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
