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Re: safe/unsafe mode

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

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