🚀 go-pugleaf

Steve Clamage (clamage@Eng.Sun.COM) wrote:
: In article q3@galaxy.ucr.edu, thp@cs.ucr.edu (Tom Payne) writes:
[...]
: >I don't mean to imply that one can portably detect *all* invalid
: >pointers, but with help from the compiler software-based solutions
: >can give coverage that is as complete as those based on hardware.
: >In either case, it is not particularly helpful that the behavior
: >becomes undefined the moment an invalid value is detected.
[...]
: Pointer validation isn't going to be portable, as I pointed out before.

The issue is not so much the portability of the checking but the
portability of programs that want to invoke it without voiding their
defined-behavior contract with the underlying implemention.

: I don't see any advantage in trying to restrict the kind or form of checking
: that systems are allowed to implement. I would applaud a hardware-based
: mechanism, and I would resent a programming language standard that made
: it non-conforming.

The issue is not the form of the checking but the response to it.  The
standard response to a hardware-detected fault is to invoke a signal
handler, which is (or should be) completely conforming.

Tom Payne (thp@cs.ucr.edu)



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