Since 2afa019c70,
the Meson configure step will fail when building from tarball (missing `.git` and `gitversion.h` is present)
because `gitversion_h` variable will contain a `list[file]` but `custom_target` does not like that in its `depends` kwarg.
This is untested on my side, because the bug only happens on native
builds with meson (our CI has cross-builds with meson and native builds
with autotools and I only do cross-builds locally) but I think/hope it
will work.
Basically we were using .full_path() because these rc files were also
used as input of some configure_file() calls which doesn't like custom
target objects as input (it wants strings or file objects). Yet a bug
in meson didn't like the colon used in native Windows full paths ('C:'
and such) when used in windows.compile_resources(). This has been fixed
by Luca Bacci in: https://github.com/mesonbuild/meson/pull/9368
Yet we just cannot depend on very early meson (or worse dev meson code).
On the other hand, if the input is a custom_tgt object, it uses the
object ID which we give as first parameter of custom_target() so we know
it's appropriately named without colons (such as 'gimp_plugins_rc').
Thus we should not bump into this issue again.
For the few usage in configure_file(), I just add a .full_path() only
when needed at call time.
Last but not least, I replace the bogus `meson --version` call by a
`python3 -c 'exit()'` as advised by Eli Schwartz:
2afa019c70 (note_1284951)
The reason is that it is apparently possible (or will be when some
reimplementation of meson will be done) that the `meson` executable
itself does not exist. On the other hand, `python3` should always be
there, as a mandatory dependency of the build tool.
In order to use an appropriate `python3`, I made the
pythonmod.find_installation() check required in our build (which should
not be a problem since it's a meson requirement as well), even when the
-Dpython option is false (this one depends on other requirements too
anyway, such as version and pygobject). This way I can call this meson
variable of discovered python in my bogus call, instead of calling a
(potentially different) python from PATH environment.
by adding special filler custom_target() build rules.
Basically, these build rules do nothing (a mere meson --version call),
but they ensure that `git-version.h` is built first, before the dependant
rc files are used in respective resource compiler build targets.
This still a nasty trick (not a proper solution), but it do the job.
See #6257 for additional information.
Jan Tojnar