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

pari: update to 2.15.2.
https://github.com/void-linux/void-packages/pull/42016

Description:
Also:
 - use -flto=auto for multithreaded link
 - change build so we don't need to patch makefile
 - ship pdf documentation in addtion to dvi
 - use SOURCE_DATE_EPOCH for dvi files
 - backport fix for pari bug 2441

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