There is an updated pull request by motorto against master on the void-packages repository

https://github.com/motorto/void-packages imath
https://github.com/void-linux/void-packages/pull/39852

openexr3.0 update
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#### Testing the changes
- I tested the changes in this PR: **YES**

#### New package
- This new package conforms to the [package requirements](https://github.com/void-linux/void-packages/blob/master/CONTRIBUTING.md#package-requirements): **YES**

#### Local build testing
- I built this PR locally for my native architecture, x86_64-{musl,glibc}

TODO:

Missing cross on imath-python3

[ci skip]

A patch file from https://github.com/void-linux/void-packages/pull/39852.patch is attached