Commit Graph

7 Commits

Author SHA1 Message Date
Akihiko Odaki
414b180d42 meson: Pass objects and dependencies to declare_dependency()
We used to request declare_dependency() to link_whole static libraries.
If a static library is a thin archive, GNU ld keeps all object files
referenced by the archive open, and sometimes exceeds the open file limit.

Another problem with link_whole is that suboptimal handling of nested
dependencies.

link_whole by itself does not propagate dependencies. In particular,
gnutls, a dependency of crypto, is not propagated to its users, and we
currently workaround the issue by declaring gnutls as a dependency for
each crypto user.  On the other hand, if you write something like

  libfoo = static_library('foo', 'foo.c', dependencies: gnutls)
  foo = declare_dependency(link_whole: libfoo)

  libbar = static_library('bar', 'bar.c', dependencies: foo)
  bar = declare_dependency(link_whole: libbar, dependencies: foo)
  executable('prog', sources: files('prog.c'), dependencies: [foo, bar])

hoping to propagate the gnutls dependency into bar.c, you'll see a
linking failure for "prog", because the foo.c.o object file is included in
libbar.a and therefore it is linked twice into "prog": once from libfoo.a
and once from libbar.a.  Here Meson does not see the duplication, it
just asks the linker to link all of libfoo.a and libbar.a into "prog".

Instead of using link_whole, extract objects included in static libraries
and pass them to declare_dependency(); and then the dependencies can be
added as well so that they are propagated, because object files on the
linker command line are always deduplicated.

This requires Meson 1.1.0 or later.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-ID: <20240524-objects-v1-1-07cbbe96166b@daynix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-07-03 18:41:25 +02:00
Paolo Bonzini
9c05071719 pythondeps.toml: warn about updates needed to docs/requirements.txt
docs/requirements.txt is expected by readthedocs and should be in sync
with pythondeps.toml.  Add a comment to both.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2024-04-23 17:35:26 +02:00
Philippe Mathieu-Daudé
1a1e889f35 buildsys: Bump known good meson version to v1.2.3
We need meson v1.2.3 to build QEMU on macOS Sonoma.  It
also builds fine all our CI jobs (as tested by also bumping
"accepted" in pythondeps.toml), so let's use it as our
"good enough" packaged wheel.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1939
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231109160504.93677-2-philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-24 16:21:55 +01:00
Paolo Bonzini
6dc8a88785 docs: document what configure does with virtual environments
Given the recent confusion around how QEMU detects the system
Meson installation, and/or decides to install its own, it is
time to fill in the "Python virtual environments and the QEMU
build system" section of the documentation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-11-24 16:21:51 +01:00
Paolo Bonzini
c03f57fd5b Revert "tests: Use separate virtual environment for avocado"
This reverts commit e8e4298fea.

ensuregroup allows to specify both the acceptable versions of avocado,
and a locked version to be used when avocado is not installed as a system
pacakge.  This lets us install avocado in pyvenv/ using "mkvenv.py" and
reuse the distro package on Fedora and CentOS Stream (the only distros
where it's available).

ensuregroup's usage of "(>=..., <=...)" constraints when evaluating
the distro package, and "==" constraints when installing it from PyPI,
makes it possible to avoid conflicts between the known-good version and
a package plugins included in the distro.

This is because package plugins have "==" constraints on the version
that is included in the distro, and, using "pip install avocado==88.1"
on a venv that includes system packages will result in an error:

   avocado-framework-plugin-varianter-yaml-to-mux 98.0 requires avocado-framework==98.0, but you have avocado-framework 88.1 which is incompatible.
   avocado-framework-plugin-result-html 98.0 requires avocado-framework==98.0, but you have avocado-framework 88.1 which is incompatible.

But at the same time, if the venv does not include a system distribution
of avocado then we can install a known-good version and stick to LTS
releases.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1663
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-08-28 09:55:48 +02:00
Paolo Bonzini
c853c4d087 configure: switch to ensuregroup
Using the new ensuregroup command, the desired versions of meson and
sphinx can be placed in pythondeps.toml rather than configure.

The meson.install entry in pythondeps.toml matches the version that is
found in python/wheels.  This ensures that mkvenv.py uses the bundled
wheel even if PyPI is enabled; thus not introducing warnings or errors
from versions that are more recent than the one used in CI.

The sphinx entries match what is shipped in Fedora 38.  It's the
last release that has support for older versions of Python (sphinx 6.0
requires Python 3.8) and especially docutils (of which sphinx 6.0 requires
version 0.18).  This is important because Ubuntu 20.04 has docutils 0.14
and Debian 11 has docutils 0.16.

"mkvenv.py ensure" is only used to bootstrap tomli.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-08-28 09:55:48 +02:00
Paolo Bonzini
71ed611cd4 python: mkvenv: add ensuregroup command
Introduce a new subcommand that retrieves the packages to be installed
from a TOML file. This allows being more flexible in using the system
version of a package, while at the same time using a known-good version
when installing the package.  This is important for packages that
sometimes have backwards-incompatible changes or that depend on
specific versions of their dependencies.

Compared to JSON, TOML is more human readable and easier to edit.  A
parser is available in 3.11 but also available as a small (12k) package
for older versions, tomli.  While tomli is bundled with pip, this is only
true of recent versions of pip.  Of all the supported OSes pretty much
only FreeBSD has a recent enough version of pip while staying on Python
<3.11.  So we cannot use the same trick that is in place for distlib.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-08-28 09:55:36 +02:00