Ping Re: Implement C23 log2p1

[Joseph Myers]

I'd like to ping this patch 
<https://sourceware.org/pipermail/libc-alpha/2024-April/155960.html>, and, 
in particular:

(a) the actual content of the patch, which no-one has commented on 
(instead preferring to suggest other things to add to it);

(b) the questions of what goes in such patches, where I argue that we 
should not expect libm-test-ulps updates for more than one architecture, 
or additional test inputs based on searches for worst-case inputs, to be 
included in such a patch: that it should be sufficient to include 
libm-test-ulps updates for a single architecture, and tests that seem 
appropriate based on the mathematical properties of the function being 
tested, and further additions there can reasonably be made in followup 
patches.  (Note that even if we moved to a single libm-test-ulps shared 
between architectures and listing expected ulps based on floating-point 
format rather than type, it still wouldn't be possible to update all ulps 
on a single system: no architecture supports both ldbl-96 and 
ldbl-128ibm.)

-- 
Joseph S. Myers
josmyers@redhat.com