C out-of-bound pointer question
Dag-Erling Smørgrav
des at des.no
Fri Nov 16 06:02:48 PST 2007
Oliver Fromme <olli at lurza.secnetix.de> writes:
> It is true that the k[] array in v2.0 uses 1 GB of mapped memory,
> *BUT* it does not use 1 GB of RAM. It only uses one page of physical
> RAM. Remember that RAM is allocated dynamically when it is accessed
> for the first time, so if you never access k[0..268435409], then no
> RAM will be allocated for it. Of course, you should make sure that it
> is a local variable (or a malloc()ed one) that is not initialized, or
> otherwise the initialization will cause RAM to be allocated. Make
> sure you initialize only the indices that you need.
It can't be a local variable; it's larger than the stack.
DES
--
Dag-Erling Smørgrav - des at des.no
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