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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Subject: Re: Compiler default initialization of array types
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Kilgallen@SpamCop.net (Larry Kilgallen) writes:

> Efficiency will depend on the compiler and potentially the operating
> system.  For package-level data on VMS, compilers that need a lot of
> zeroed memory will typically emit linker instructions to "fake it"
> with manipulation of the memory management system.

The zero-page tricks of VMS are nice, but they couldn't help in the case
I mentioned.  Nor could compiler optimizations, unless the compiler was
*really* clever.

These objects were heap-allocated.  An OS can use virtual-memory tricks
to produce huge arrays of zero pages, but it seems infeasible to always
go directly to the OS for every "new".

- Bob