There is a new pull request by oreo639 against master on the void-packages repository

https://github.com/oreo639/void-packages llvm12
https://github.com/void-linux/void-packages/pull/38694

llvm12: fix build for glibc 2.36
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#### Testing the changes
- I tested the changes in this PR: **YES**

This patch is necessary to build on glibc 2.36 due to an incompatibility between `<linux/mount.h>` and `<sys/mount.h>`.
More information can be found here:
https://sourceware.org/glibc/wiki/Release/2.36

The build failure can be confirmed here: https://github.com/void-linux/void-packages/pull/34902

[ci skip]

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- I built this PR locally for my native architecture, (x86_64-glibc)
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A patch file from https://github.com/void-linux/void-packages/pull/38694.patch is attached