There's a closed pull request on the void-packages repository

imath: update to 3.1.8.
https://github.com/void-linux/void-packages/pull/44127

Description:
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#### Testing the changes
- I tested the changes in this PR: **YES**

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

EDIT: They seem to be always changing the shlib ...