[Cfp-interest] SNAN and thread storage

[Fred J. Tydeman]

On Thu, 19 Apr 2012 09:51:51 -0700 (PDT) Fred J. Tydeman wrote:
>
>On Thu, 19 Apr 2012 09:26:49 -0700 (PDT) Fred J. Tydeman wrote:
>>
>>The description of SNAN on page 23/17 for 7.12#5 mentions
>>static initializer.  What about thread storage?
>
>Jim wrote:
>>Please say more about the issue you see with thread storage.
>
>My understanding is thread storage is initialized from a static
>image created at translation time.  So, a floating thread var
>initialized with an SNAN should be the same as a static var
>(and not like an auto var).
>
>
>How about replacing
>
>If a signaling NaN macro is used as a static initializer 
>for an object of the same type, the object is initialized with a
>signaling NaN value.
>
>with
>
>If a signaling NaN macro is used as a static or thread initializer 
>for an object of the same type, the object is initialized with a
>signaling NaN value.

Here is the words I have come up with after looking more at C11:

If a signaling NaN macro is used for initialization of an object that
has static or thread-local storage duration of the same type, the
object is initialized with a signaling NaN value.


---
Fred J. Tydeman        Tydeman Consulting
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