Cycle in CMake inputs/dependencies detected with libavif subproject

[Teselka]

Describe the bug
When trying to build libavif 1.1.1 as subproject meson fails with an error.
meson-log.txt

To Reproduce
Clone libavif into the subprojects dir and run meson setup build
test_libavif.zip

Expected behavior
Normal build setup

system parameters

• Is this a cross build or just a plain native build (for the same computer)?
  native
• what operating system (e.g. MacOS Catalina, Windows 10, CentOS 8.0, Ubuntu 18.04, etc.)
  Windows 10
• what Python version are you using e.g. 3.8.0
  Python 3.7.9
• what meson --version
1.5.0
• what ninja --version if it's a Ninja build
  1.12.1

[dcbaker]

I can reproduce this on Linux, so it doesn't appear to be Windows specific. I haven't looked into it further, but it seems from the updated error message in the linked PR that this is a bug on our end.

[dcbaker]

This is actually happening in the svc-src sub-subprojct (Yay for CMake's non-standard subprojects :/), and is (I think) caused by us not handling BYPRODUCTS, which means that we end up treating a command line arguments that has the output, as if it's an input.