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[Python-Dev] Bugs in thread_nt.h

Neil Hodgson nyamatongwe at gmail.com
Thu Mar 10 13:55:59 CET 2011 
Martin v. Löwis:

> I guess all this advice doesn't really apply to this case, though.
> The Microsoft API declares the parameter as a volatile*, indicating
> that they consider it "proper" usage of the API to declare the storage
> volatile.

   The 'volatile' here is a modifier on the parameter and does not
require a corresponding agreement in the variable declaration. It
indicates that all access through the pointer inside the function will
be with volatile semantics. As long as all functions that operate on
the variable do so treating access as volatile then everything is
fine. You should only need to declare the variable as volatile if
there is other code that accesses it directly.

   If agreement was required then the compiler would print a warning.

   It is similar to declaring a function to take a const parameter:
there is no need for the variable to also be const.

   Neil
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