RE: Live range splitting in new allocator

[David Korn <dkorn at pixelpower dot com>]

>Seriously, though, Robert does have a point; the perfect can be the enemy
>of the good.  And I've even used the technique back when I did embedded
>systems stuff, initializing "uninitialized memory" to 0xdeadbeef because
>it looked cool on the screen of our emulator:
>
>001000 DEAD BEEF DEAD BEEF ....

  This is particularly good on systems like Ppc that don't support unaligned
accesses because it's an odd number, and you're twice as likely to get an
exception the moment you try and use it for anything.  My favourites include
0xBADF00D, 0xDEADF00D, 0xBADC0DED and if I'm not too bothered about odd
numbers 0xF00DFACE and 0xBADCAFE; I'll use one to mung the lo memory and
fill in unused exception vectors, another to fill before and after malloc'ed
blocks, and in a lot of cases you can then spot the difference between a 
NULL ptr deref and an array overrun just by checking the pc when your code
excepts.

  <sigh>I guess that's the nearest to fun that coding ever gets to be...
 
        DaveK
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