docs/devel/build-system.rst

40  - list the targets for which to build emulators; the list of
52    configuration step for the emulator build
54 The configure script automatically recognizes command line options for
85   Detect a cross compiler and cross tools for the QEMU target $TARGET (e.g.,
96 Configure does not generally perform tests for compiler options beyond
116    therefore can be used to check for cross compilers.  However, most
117    such checks are done at ``make`` time instead (see for example the
137 look for ``meson`` or ``sphinx-build`` binaries in the PATH;
147 If a package is available for the chosen interpreter, ``configure``
196 The Meson build system describes the build and install process for:
215 All executables are built by default, except for some ``contrib/``
216 binaries that are known to fail to build on some platforms (for example
229   their own sourceset, for example ``block_ss`` for the block device subsystem,
230   ``chardev_ss`` for the character device subsystem, etc.  These sourcesets
253   once for each target being built.  Target-dependent files are included
256   Each emulator also includes sources for files in the ``hw/`` and ``target/``
257   subdirectories.  The subdirectory used for each emulator comes
262   for example::
269   The sourceset is only used for system emulators.
273   for all emulators and for system emulators only.  For example::
282   There are two dictionaries for modules: ``modules`` is used for
283   target-independent modules and ``target_modules`` is used for
290   the toplevel dictionaries.  For example::
303   The separation between these two is purely for documentation purposes.
332   file for each emulator\ [#cfgtarget]_.  However, the ``TARGET_ARCH``
340 new target, or enabling new devices or hardware for a particular
363 Taking the probe for SDL2_Image as an example, we have the following
367          description: 'SDL Image support for icons')
379 This avoids warnings on static builds of user-mode emulators, for example.
380 Most of the libraries used by system-mode emulators are not available for
391 For the configure script to parse the new option, the
399 Meson has a special convention for invoking Python scripts: if their
410 executable (for example for test scripts that developers may want to
412 should be invoked through the ``python`` variable in meson.build. For
443 the smaller build systems for firmware and tests; it also takes care of
451 tests for all targets.
462   Print a help message for the most common build targets.
465   Print the value of the variable VAR. Useful for debugging the build
469 Important files for the build system
485   The meson.build file in the root directory is the main entry point for the
487   executables.  Build rules for various subdirectories are included in
491   A wrapper for the Python ``venv`` and ``distlib.scripts`` packages.
496   Rules for external test harnesses like the TCG tests.
499   Rules for Docker tests. Like ``tests/Makefile.include``, this file is
504   Rules for VM-based tests. Like ``tests/Makefile.include``, this file is
512 behaviour of the Makefiles. This avoids the need for QEMU makefiles to
520   will write the paths to various tools to this file, for use in ``Makefile``
552   A Python virtual environment that is used for all Python code running
561   and the set of enabled features for the entire build.
573   features for each target.  enabled.  They are generated from
585   A Makefile include that bridges to ninja for the actual build.  The