[Cfp-interest 2673] Re: floating constants issue

[Vincent Lefevre]

On 2023-01-31 17:28:04 -0800, Jim Thomas wrote:
> Here’s a draft for changes to clarify that FE_DYNAMIC does not
> establish a constant rounding mode:
> 
> https://wiki.edg.com/pub/CFP/WebHome/Floating_constants_issue-20230131.pdf

Thanks.

In this draft, "constant rounding more": "change "more" to "mode".

There's also an issue in NOTE 1: this will not work for constants
("Floating constants (6.4.4.2) of a standard floating type that
occur in the scope of a constant rounding mode shall be interpreted
according to that mode.").

BTW, this rule for constants is unintuitive, thus error-prone, when
using non-symmetric rounding, because negative constants do not exist,
so that when writing "-0.1", the negation is done after rounding.
I don't know whether this has already been discussed and what could be
done. If the rule is kept as is, there should be at least an example
to warn about this issue.

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