bug 14360: dosmem forgot MAP_FIXED

[Alexandre Julliard]

John Reiser <jreiser at BitWagon.com> writes:

> Some environments strictly enforce the semantics of mmap(), namely a successful
> return value need not equal the requested address unless MAP_FIXED,
> even if the requested address is unmapped and otherwise available.
> Unless MAP_FIXED, then it is legal to return any page range that is large enough.
> Callers of the patched code were relying on getting actual fixed addresses
> in the interval [0, 0x110000).  In particular, this did not work under valgrind.

You can't use MAP_FIXED on an address that you are not sure is
available. If it wasn't reserved first, the best we can do is request
the address, and refuse to support DOS apps if we don't get it. If you
want to make this work in all cases you have to fix valgrind to allow
the preloader to do its job.

-- 
Alexandre Julliard
julliard at winehq.org