> You need compiler/language support to ensure atomics are handled properly
That's an assumption that you're treating as though it somehow informs reality. I gave you an example of atomics being handled by a library, and the man page points to where in the source code it's defined.
> so you'd need to know how Plan 9's compiler/language specifies atomics.
It doesn't, as far as I can tell. Kencc is a very "dumb" compiler that does little magic nor does it extend the language beyond the standard C that the Bell Labs guys were used to. For whatever reasons, they found it expedient to write new libraries instead of changing the language itself. They did occasionally write compilers for new languages when they had wacky ideas that would be difficult to accomodate, like Newsqueak and Alef. In Alef's case they actually did accomodate some of it, which is how Plan 9 got libthread.
That's an assumption that you're treating as though it somehow informs reality. I gave you an example of atomics being handled by a library, and the man page points to where in the source code it's defined.
> so you'd need to know how Plan 9's compiler/language specifies atomics.
It doesn't, as far as I can tell. Kencc is a very "dumb" compiler that does little magic nor does it extend the language beyond the standard C that the Bell Labs guys were used to. For whatever reasons, they found it expedient to write new libraries instead of changing the language itself. They did occasionally write compilers for new languages when they had wacky ideas that would be difficult to accomodate, like Newsqueak and Alef. In Alef's case they actually did accomodate some of it, which is how Plan 9 got libthread.