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Re: safe/unsafe mode



Sebastian Egner <sebastian.egner@xxxxxxxxxxx> writes:

> Mike wrote:
>> From this, and several other messages in the SRFI 77 archives, I'm
>> getting the impression there's some misunderstanding here about the
>> nature of safe/unsafe mode, as alluded to in the document.
>
> Always possible. I understand safe/unsafe mode to mean that there is
> some form of global switch (either compile-time or run-time) that is
> controlling whether certain arithmetic operations raise an exception
> when an error condition happens---or just press on. I understand that
> the 'unsafe' mode allows a compiler to produce code without range
> checking or tag-bit removal, with all sorts of performance benefits. Is
> this what you mean by safe/unsafe mode?

No.  As I wrote (and SRFI 77 is pretty explicit about it), it affects
only *type checking* of the FL... and FX... operations.  It has no
effect on range checking.  (I'm not sure what range checking could
mean in the context of SRFI 77.)

-- 
Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla