Are you sure that is the problem? It seems to me that this file is generated by qemu's configure script. I was able to get further building qemu by running

mkdir build
cd build
../configure --meson=muon

When configure gets to the actual meson invocation, it fails due to passing invalid arguments. After that you can run muon setup build from the project root as usual.

I was able to get pretty far with muon setup -Dvfio_user_server=disabled -Dnettle=enabled build. The next big thing to implement is the sourceset module, which I am working on right now :)

Yes, you are right. Sorry, at that day I was too tired and forgot that QEMU uses ./configure first. I saw you also implemented the "sourceset" module, but there is a new problem:

warn dependency ['gnutls'] not found
/home/xvilka/qemu/meson.build:1155:25: error unsupported dependency method 'config-tool'
1155 |                         method: 'config-tool',
                               ^
/home/xvilka/qemu/meson.build:1154:14: error in function dependency()
1154 |     gcrypt = dependency('libgcrypt', version: '>=1.8',
                    ^

Muon does not support custom (non-pkgconfig) dependencies for the most part. IIRC there's a framework stub for it and one or two (threads?) is actually implemented...

Correct, although there is a pending patch that would cause the method to be effectively ignored. In this specific case, I was able to bypass this dependency check by using nettle instead of gcrypt (-Dnettle=enabled).

The above patch with some modifications was applied, which means that the gcrypt lookup should result in a not-found dependency without erroring.

Now it fails because there is no --native-file option (or --cross-file conversely) in the muon setup.

This is what it feeds as the --native-file build/config-meson.cross:

# Automatically generated by configure - do not modify
[properties]
[built-in options]
c_args = []
cpp_args = []
objc_args = []
c_link_args = []
cpp_link_args = []
[binaries]
c = ['cc','-m64','-mcx16']
cpp = ['c++','-m64','-mcx16']
objc = ['clang','-m64','-mcx16']
ar = ['ar']
nm = ['nm']
pkgconfig = ['pkg-config']
ranlib = ['ranlib']
sdl2-config = ['sdl2-config']
strip = ['strip']
widl = ['widl']
windres = ['windres']
windmc = ['windmc']

~xvilka I'm pretty sure you can bypass that by running muon setup directly. See my above comment

When configure gets to the actual meson invocation, it fails due to passing invalid arguments. After that you can run muon setup build from the project root as usual.

Since qemu drives meson with a somewhat complicated script that relies on meson's cli, I think qemu support would probably need either a meson cli compatibility layer or the qemu devs to explicitly handle muon. I originally was against it, but now think it would probably be in muon's best interests to implement the former. It is on my todo list.

~xvilka I have implemented a basic compatibility layer. Can you test and see how far you get building qemu? I'm wondering if it is possible without machine-file support.

It fails with missing i18n, I will send a patch to QEMU shortly

meson.build:4:8: error module 'i18n' is unimplemented,
  If you would like to make your build files portable to muon, use `import('i18n', required: false)`, and then check the .found() method before use.
  4 |   i18n.gettext(meson.project_name(),
             ^
qemu/meson.build:3640:3: error in function subdir()
3640 |   subdir('po')
         ^