[PATCH v2 01/12] math: Use acosh from CORE-MATH

[Paul Zimmermann]

       Hi,

there were two corrections upstream to deal with corner cases:

commit 69062c4d177a3114b9fc3d488e1644dc6b990c10
Author: Alexei Sibidanov <sibid@uvic.ca>
Date:   Thu Sep 18 09:15:20 2025 -0700

    [acosh] increase the error one more time after another failure has been discovered

commit dbd2a6380499ec03ab3f9891ffadc0e1adc940a5
Author: Alexei Sibidanov <sibid@uvic.ca>
Date:   Wed Sep 17 10:33:02 2025 -0700

    [acosh] adjust error boundary to treat found failures

The new value below passes all known test values (unfortunately an
exhaustive test is not possible).

Paul

> From: DJ Delorie <dj@redhat.com>
> Cc: libc-alpha@sourceware.org, Wilco.Dijkstra@arm.com,
>         Paul.Zimmermann@inria.fr
> Date: Thu, 23 Oct 2025 18:48:11 -0400
> 
> Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:
> 
> > +      double eps = ds * 0x1.04p-50 - 0x1p-104 * sh;
> 
> Note: this was 0x1.fcp-51 in v1, but I see nothing to explain the
> change...
> 
>