strangest systems I've sent email from

Mouse mouse at Rodents-Montreal.ORG
Fri May 20 21:36:02 CDT 2016

>   -spc (Wish the C standard committee had the balls to say "2's
>   complement all the way, and a physical bit pattern of all 0s is a
>   NULL pointer" ... )

As far as I'm concerned, this is different only in degree from `Wish
the C standard committee had the balls to say "Everything is x86".'.

> [3]	Often to disasterous results.  An agressive C optimizer can
>       optimize the following right out:

> 		if (x + 1 < x ) { ... }

> 	Because "x+1" can *never* be less than "x" (signed overflow?
> 	What's that?)

More precisely, because signed overflow invokes undefined behaviour,
meaning that, for values of x where x+1 overflows, the program can
behave in any way whatever and still be within spec.  Including, say,
skipping the stuff inside the { } block.

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