ERROR: Unhandled python exception while building babl

[n01r1r]

Hello all.

I'm new to meson, much as cmake or other building tools.
This might be a beginner's mistake, so if there is any please let me know.

I am trying to build GIMP from source in Ubuntu on WSL2.
following these instructions:
https://developer.gimp.org/core/setup/build/linux/
https://discourse.gnome.org/t/first-time-gimp-build/15245

In process I've been told to build and install babl using meson setup _build --prefix=/usr/local which returned

The Meson build system
Version: 1.4.0
Source dir: /home/n01r/babl
Build dir: /home/n01r/babl/_build
Build type: native build
Project name: babl
Project version: 0.1.109
C compiler for the host machine: cc (gcc 11.4.0 "cc (Ubuntu 11.4.0-1ubuntu1~22.04) 11.4.0")
C linker for the host machine: cc ld.bfd 2.38
Host machine cpu family: x86_64
Host machine cpu: x86_64
Program python3 found: YES (/usr/bin/python3)
Message: Host os: linux
Message: Build os: linux
Compiler for C supports arguments -Ofast: YES
Compiler for C supports arguments -fno-unsafe-math-optimizations: YES
Compiler for C supports arguments -ftree-vectorize: YES
Compiler for C supports arguments -Wdeclaration-after-statement: YES
Compiler for C supports arguments -Winit-self: YES
Compiler for C supports arguments -Wmissing-declarations: YES
Compiler for C supports arguments -Wmissing-prototypes: YES
Compiler for C supports arguments -Wold-style-definition: YES
Compiler for C supports arguments -Wpointer-arith: YES
Compiler for C supports arguments -march=x86-64: YES
Compiler for C supports arguments -msse2: YES
Compiler for C supports arguments -msse2: YES (cached)
Compiler for C supports arguments -msse4.1: YES
Compiler for C supports arguments -msse4.2: YES
Compiler for C supports arguments -mpopcnt: YES
Compiler for C supports arguments -mssse3: YES
Compiler for C supports arguments -mavx: YES
Compiler for C supports arguments -mavx2: YES
Compiler for C supports arguments -mf16c: YES
Compiler for C supports arguments -mfma: YES
Compiler for C supports arguments -mmovbe: YES
Compiler for C supports arguments -mbmi: YES
Compiler for C supports arguments -mbmi2: YES
Compiler for C supports arguments -mmmx: YES
Message: mmx assembly available
Compiler for C supports arguments -msse: YES
Message: sse assembly available
Compiler for C supports arguments -mfpmath=sse: YES
Compiler for C supports arguments -msse2: YES (cached)
Message: sse2 assembly available
Compiler for C supports arguments -msse4.1: YES (cached)
Message: sse4.1 assembly available
Compiler for C supports arguments -mavx2: YES (cached)
Message: avx2 assembly available
Compiler for C supports arguments -mf16c: YES (cached)
Message: Can compile half-floating point code (f16c)
Has header "stdatomic.h" : YES
Has header "dlfcn.h" : YES
Has header "dl.h" : NO
Checking for function "gettimeofday" : YES
Checking for function "rint" : NO
Checking for function "srandom" : YES
Library m found: YES
Run-time dependency threads found: YES
Library dl found: YES
Found pkg-config: YES (/usr/bin/pkg-config) 0.29.2
Run-time dependency gobject-introspection-1.0 found: YES 1.72.0
Run-time dependency lcms2 found: YES 2.12
Did not find CMake 'cmake'
Found CMake: NO
Run-time dependency vapigen found: NO (tried pkgconfig and cmake)
Program git found: YES (/usr/bin/git)
Program env found: YES (/usr/bin/env)
Program rsvg-convert found: NO
Program w3m found: NO
Program gi-docgen found: NO
Configuring config.h using configuration
Program gen_babl_map.py found: YES (/usr/bin/python3 /home/n01r/babl/gen_babl_map.py)
Checking if "-Wl,--version-script" : links: YES
Configuring babl-version.h using configuration
Dependency gobject-introspection-1.0 found: YES 1.72.0 (cached)
Dependency gobject-introspection-1.0 found: YES 1.72.0 (cached)
Program /usr/bin/g-ir-scanner found: YES (/usr/bin/g-ir-scanner)
Dependency gobject-introspection-1.0 found: YES 1.72.0 (cached)
Program /usr/bin/g-ir-compiler found: YES (/usr/bin/g-ir-compiler)
Program tools/xml-insert.py found: YES (/usr/bin/python3 /home/n01r/babl/tools/xml-insert.py)
Configuring index-static.html using configuration
docs/meson.build:71: DEPRECATION: Project uses feature that was always broken, and is now deprecated since '1.3.0': str.format: Value other than strings, integers, bools, options, dictionaries and lists thereof..
Build targets in project: 110
NOTICE: Future-deprecated features used:
 * 0.62.0: {'pkgconfig.generate variable for builtin directories'}
 * 0.64.0: {'copy arg in configure_file'}
 * 1.1.0: {'"boolean option" keyword argument "value" of type str'}
WARNING: Broken features used:
 * 1.3.0: {'str.format: Value other than strings, integers, bools, options, dictionaries and lists thereof.'}

babl 0.1.109

  Directories
    prefix                  : /usr/local
    libdir                  : lib/x86_64-linux-gnu

  Optional features
    BABL docs (babl website): true
    gi-docgen               : false
    Introspection           : true
    VALA support            : false

  Processor extensions
    mmx                     : true
    sse                     : true
    sse2                    : true
    sse4_1                  : true
    avx2                    : true
    f16c (half fp)          : true

  Optional dependencies
    lcms                    : true

  User defined options
    prefix                  : /usr/local

Found ninja-1.10.1 at /usr/bin/ninja

after this I've entered meson compile -C _build, which returned

INFO: autodetecting backend as ninja
INFO: calculating backend command to run: /usr/bin/ninja -C /home/n01r/babl/_build
ninja: Entering directory `/home/n01r/babl/_build'
[177/283] Compiling C object bin/babl.p/babl.c.o
../bin/babl.c: In function ‘babl_cli_get_space’:
../bin/babl.c:542:3: warning: ignoring return value of ‘fread’ declared with attribute ‘warn_unused_result’ [-Wunused-resul]
  542 |   fread (icc_data, icc_length, 1, f);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[283/283] Generating docs/Reference.html with a custom command

and when I tried sudo meson install -C _build, it returned

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/mesonbuild/mesonmain.py", line 146, in run
    return options.run_func(options)
  File "/usr/lib/python3/dist-packages/mesonbuild/minstall.py", line 797, in run
    b = build.load(opts.wd)
  File "/usr/lib/python3/dist-packages/mesonbuild/build.py", line 2868, in load
    obj = pickle.load(f)
ModuleNotFoundError: No module named 'mesonbuild.utils'

ERROR: Unhandled python exception

    This is a Meson bug and should be reported!

Is there any dependencies that should be pre-installed, or other settings that should be checked?
Thanks in advance :)

[eli-schwartz]

and when I tried sudo meson install -C _build, it returned

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/mesonbuild/mesonmain.py", line 146, in run
    return options.run_func(options)
  File "/usr/lib/python3/dist-packages/mesonbuild/minstall.py", line 797, in run
    b = build.load(opts.wd)
  File "/usr/lib/python3/dist-packages/mesonbuild/build.py", line 2868, in load
    obj = pickle.load(f)
ModuleNotFoundError: No module named 'mesonbuild.utils'

ERROR: Unhandled python exception

    This is a Meson bug and should be reported!

This indicates that sudo meson install is trying to get a Ubuntu packaged version of meson installed to the root account (in /usr, to be specific).

Which Ubuntu version are you using? Did you have to manually install a newer version of meson?

Gimp needs meson 0.61.0, which should be available via sudo apt install meson on Ubuntu 22.04 and later, so you don't need to manually install your own.

The issue with sudo is discussed at https://mesonbuild.com/Getting-meson.html#installing-meson-with-pip but tl;dr if you pip install --user meson then you cannot run meson with sudo -- it will either report the command doesn't exist or it will try to load an incompatible different version of meson that crashes.

We fixed the crash in newer versions of meson so that instead it just tells you you tried to run an incompatible version of meson. :)

[n01r1r]

Indeed, I'm using Ubuntu 22.04.4 LTS.
I do not remember if I manually installed meson, so I've checked by following:

Upon entering meson -v it returns 1.4.0,
But trying sudo apt install meson it says:

Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
meson is already the newest version (0.61.2-1).
0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.

meaning that I have somehow have 2 different versions of meson installed, thus the error ocuuring?

[eli-schwartz]

Yes.

You can try pip uninstall --user meson and then recreate the meson build directory.