New comment by ackalker on void-packages repository

https://github.com/void-linux/void-packages/issues/27965#issuecomment-766365866

Comment:
Back on topic for this issue: I've had a look at the Qemu source, in particular the `meson.build` file I suspect is responsible for the problem: [pc-bios/descriptors/meson.build#L11](https://github.com/qemu/qemu/blob/553032db17440f8de011390e5a1cfddd13751b0b/pc-bios/descriptors/meson.build#L11)

I don't see any particular problem with it, but I'm in no way a Meson expert. AFAICT the `configure_file` is supposed to take a file, change any references to `@DATADIR@` in it to the contents of `qemu_datadir`, and install it into the directory named by the contatenation of the value of `qemu_datadir`, a `/`, and the string `firmware`, which seems mostly what is happening during the build, except for some reason `@DATADIR@` gets substituted with `share/qemu` and not `/usr/share/qemu`, i.e. it is missing the prefix: `/usr`.
I find this very strange, as in other places, `qemu_datadir` does seem to evaluate to `/usr/share/qemu`.
Maybe some interaction going on here? Is there perhaps an environment variable `DATADIR` whose value is overriding that of the substitution?