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+---
+title: Release 0.60.0
+short-description: Release notes for 0.60.0
+...
+
+# New features
+
+## `run_target` can now be used as a dependency
+
+A `run_target()` can now be saved in a variable and reused as a dependency in
+an `alias_target()`. This can be used to create custom alias rules that ensure
+multiple other targets are run, even if those targets don't produce output
+files.
+
+For example:
+
+```
+i18n = import('i18n')
+
+all_pot_targets = []
+
+foo_i18n = i18n.gettext('foo')
+
+all_pot_targets += foo_i18n[1]
+
+alias_target('all-pot', all_pot_targets)
+```
+
+## The Python Modules dependency method no longer accepts positional arguments
+
+Previously these were igrnoed with a warning, now they're a hard error.
+
+## `unset_variable()`
+
+`unset_variable()` can be used to unset a variable. Reading a variable after
+calling `unset_variable()` will raise an exception unless the variable is set
+again.
+
+```meson
+# tests/meson.build
+tests = ['test1', 'test2']
+
+# ...
+
+unset_variable('tests')
+
+# tests is no longer usable until it is set again
+```
+
+## Override python installation paths
+
+The `python` module now has options to control where modules are installed:
+- python.platlibdir: Directory for site-specific, platform-specific files.
+- python.purelibdir: Directory for site-specific, non-platform-specific files.
+
+Those options are used by python module methods `python.install_sources()` and
+`python.get_install_dir()`. By default Meson tries to detect the correct installation
+path, but make them relative to the installation `prefix`, which will often result
+in installed python modules to not be found by the interpreter unless `prefix`
+is `/usr` on Linux, or for example `C:\Python39` on Windows. These new options
+can be absolute paths outside of `prefix`.
+
+## New `subprojects packagefiles` subcommand
+
+It is now possible to re-apply `meson.build` overlays (`patch_filename` or
+`patch_directory` in the wrap ini file) after a subproject was downloaded and
+set up, via `meson subprojects packagefiles --apply <wrap-name>`.
+
+It is also possible for `patch_directory` overlays in a `[wrap-file]`, to copy
+the packagefiles out of the subproject and back into `packagefiles/<patch_directory>/`
+via `meson subprojects packagefiles --save <wrap-name>`. This is useful for
+testing an edit in the subproject and then saving it back to the overlay which
+is checked into git.
+
+## Deprecated project options
+
+Project options declared in `meson_options.txt` can now be marked as deprecated
+and Meson will warn when user sets a value to it. It is also possible to deprecate
+only some of the choices, and map deprecated values to a new value.
+
+```meson
+# Option fully deprecated, it warns when any value is set.
+option('o1', type: 'boolean', deprecated: true)
+
+# One of the choices is deprecated, it warns only when 'a' is in the list of values.
+option('o2', type: 'array', choices: ['a', 'b'], deprecated: ['a'])
+
+# One of the choices is deprecated, it warns only when 'a' is in the list of values
+# and replace it by 'c'.
+option('o3', type: 'array', choices: ['a', 'b', 'c'], deprecated: {'a': 'c'})
+
+# A boolean option has been replaced by a feature, old true/false values are remapped.
+option('o4', type: 'feature', deprecated: {'true': 'enabled', 'false': 'disabled'})
+
+# A feature option has been replaced by a boolean, enabled/disabled/auto values are remapped.
+option('o5', type: 'boolean', deprecated: {'enabled': 'true', 'disabled': 'false', 'auto': 'false'})
+```
+
+## More efficient static linking of uninstalled libraries
+
+A somewhat common use case of [[static_library]] is to create uninstalled
+internal convenience libraries which are solely meant to be linked to other
+targets. Some build systems call these "object libraries". Meson's
+implementation does always create a static archive.
+
+This will now check to see if the static linker supports "thin archives"
+(archives which do not contain the actual object code, only references to their
+location on disk) and if so, use them to minimize space usage and speed up
+linking.
+
+## gnome.yelp variadic argument deprecation
+
+`gnome.yelp` previously allowed sources to be passed either as variadic
+arguments or as a keyword argument. If the keyword argument was given the
+variadic arguments would be silently ignored. This has changed in 0.60.0, the
+variadic form has been deprecated, and a warning is printed if both are given.
+
+## `static` keyword argument to `meson.override_dependency()`
+
+It is now possible to override shared and/or static dependencies separately.
+When the `static` keyword argument is not specified in `dependency()`, the first
+override will be used (`static_dep` in the example below).
+```meson
+static_lib = static_library()
+static_dep = declare_dependency(link_with: static_lib)
+meson.override_dependency('foo', static_dep, static: true)
+
+shared_lib = shared_library()
+shared_dep = declare_dependency(link_with: shared_lib)
+meson.override_dependency('foo', shared_dep, static: false)
+
+# Returns static_dep
+dependency('foo')
+
+# Returns static_dep
+dependency('foo', static: true)
+
+# Returns shared_dep
+dependency('foo', static: false)
+```
+
+When the `static` keyword argument is not specified in `meson.override_dependency()`,
+the dependency is assumed to follow the value of `default_library` option.
+```meson
+dep = declare_dependency(...)
+meson.override_dependency('foo', dep)
+
+# Always works
+dependency('foo')
+
+# Works only if default_library is 'static' or 'both'
+dependency('foo', static: true)
+
+# Works only if default_library is 'shared' or 'both'
+dependency('foo', static: false)
+```
+
+## `dependency()` sets `default_library` on fallback subproject
+
+When the `static` keyword argument is set but `default_library` is missing in
+`default_options`, `dependency()` will set it when configuring fallback
+subproject. `dependency('foo', static: true)` is now equivalent to
+`dependency('foo', static: true, default_options: ['default_library=static'])`.
+
+## install_emptydir function
+
+It is now possible to define a directory which will be created during
+installation, without creating it as a side effect of installing files into it.
+This replaces custom `meson.add_install_script()` routines. For example:
+
+```meson
+meson.add_install_script('sh', '-c', 'mkdir -p "$DESTDIR/@0@"'.format(path))
+```
+
+can be replaced by:
+
+```meson
+install_emptydir(path)
+```
+
+and as a bonus this works reliably on Windows, prints a sensible progress
+message, will be uninstalled by `ninja uninstall`, etc.
+
+## Cython can now transpile to C++ as an intermediate language
+
+Built-in cython support currently only allows C as an intermediate language, now
+C++ is also allowed. This can be set via the `cython_language` option, either on
+the command line, or in the meson.build files.
+
+```meson
+project(
+  'myproject',
+  'cython',
+  default_options : ['cython_language=cpp'],
+)
+```
+
+or on a per target basis with:
+```meson
+python.extension_module(
+  'mod',
+  'mod.pyx',
+  override_options : ['cython_language=cpp'],
+)
+```
+
+## New custom dependency for iconv
+
+```
+dependency('iconv')
+```
+
+will now check for the functionality of libiconv.so, but first check if it is
+provided in the libc (for example in glibc or musl libc on Linux).
+
+## Unknown options are now always fatal
+
+Passing unknown options to "meson setup" or "meson configure" is now
+always fatal. That is, Meson will exit with an error code if this
+happens. Previous Meson versions only showed a warning message.
+
+## Install DESTDIR relative to build directory
+
+When `DESTDIR` environment or `meson install --destdir` option is a relative path,
+it is now assumed to be relative to the build directory. An absolute path will be
+set into environment when executing scripts. It was undefined behavior in prior
+Meson versions but was working as relative to build directory most of the time.
+
+## Java Module
+
+The Java module has been added to Meson. The Java module allows users to
+generate native header files without needing to use a `custom_target()`.
+
+```meson
+jmod = import('java')
+
+native_header = jmod.generate_native_header('File.java', package: 'com.mesonbuild')
+native_header_includes = include_directories('.')
+
+jdkjava = shared_module(
+  'jdkjava',
+  [native_header_includes, other_sources],
+  dependencies : [jdk],
+  include_directories : [native_header_includes]
+)
+```
+
+== Link tests can use sources for a different compiler ==
+
+Usually, the `links` method of the compiler object uses a single program
+invocation to do both compilation and linking.  Starting with this version,
+whenever the argument to `links` is a file, Meson will check if the file
+suffix matches the compiler object's language.  If they do not match,
+as in the following case:
+
+```
+cxx = meson.get_compiler('cpp')
+cxx.links(files('test.c'))
+```
+
+then Meson will separate compilation and linking.  In the above example
+`test.c` will be compiled with a C compiler and the resulting object file
+will be linked with a C++ compiler.  This makes it possible to detect
+misconfigurations of the compilation environment, for example when the
+C++ runtime is not compatible with the one expected by the C compiler.
+
+For this reason, passing file arguments with an unrecognized suffix to
+`links` will cause a warning.
+
+## Relax restrictions of `str.join()`
+
+Since 0.60.0, the [[str.join]] method can take an arbitrary number of arguments
+instead of just one list. Additionally, all lists past to [[str.join]] will now
+be flattened.
+
+## Improvements for the Rustc compiler
+
+- Werror now works, this set's `-D warnings`, which will cause rustc to error
+  for every warning not explicitly disabled
+- warning levels have been implemented
+- support for meson's pic has been enabled
+
+## The qt modules now accept generated outputs as inputs for qt.compile_*
+
+This means you can uset `custom_target`, custom_target indices
+(`custom_target[0]`, for example), or the output of `generator.process` as
+inputs to the various `qt.compile_*` methods.
+
+```meson
+qt = import('qt5')
+
+ct = custom_target(...)
+
+out = qt.compile_ui(sources : ct)
+```
+
+## Waf support in external-project module
+
+If the first argument is `'waf'`, special treatment is done for the
+[waf](https://waf.io/) build system. The waf executable must be
+found either in the current directory, or in system `PATH`.
+
+## Comparing two objects with different types is now an error
+
+Using the `==` and `!=` operators to compare objects of different (for instance
+`[1] == 1`) types was deprecated and undefined behavior since 0.45.0 and is
+now a hard error.
+
+## Installation tags
+
+It is now possible to install only a subset of the installable files using
+`meson install --tags tag1,tag2` command line.
+
+See [documentation](Installing.md#installation-tags) for more details.
+
+## Compiler.unittest_args has been removed
+
+It's never been documented, and it's been marked deprecated for a long time, so
+let's remove it.
+
+## Dependencies with multiple names
+
+More than one name can now be passed to `dependency()`, they will be tried in order
+and the first name to be found will be used. The fallback subproject will be
+used only if none of the names are found on the system. Once one of the name has
+been found, all other names are added into the cache so subsequent calls for any
+of those name will return the same value. This is useful in case a dependency
+could have different names, such as `png` and `libpng`.
+
+## i18n module now returns gettext targets
+
+`r = i18n.gettext('mydomain')` will now provide access to:
+- a list of built .mo files
+- the mydomain-pot maintainer target which updates .pot files
+- the mydomain-update-po maintainer target which updates .po files
+
+## Added support for CLA sources when cross-compiling with the C2000 toolchain
+
+Support for CLA sources has been added for cross-compilation with the C2000 toolchain.
+
+## Support for clippy-driver as a rustc wrapper
+
+Clippy is a popular linting tool for Rust, and is invoked in place of rustc as a
+wrapper. Unfortunately it doesn't proxy rustc's output, so we need to have a
+small wrapper around it so that Meson can correctly detect the underlying rustc,
+but still display clippy
+
+## Force Visual Studio environment activation
+
+Since `0.59.0`, meson automatically activates Visual Studio environment on Windows
+for all its subcommands, but only if no other compilers (e.g. `gcc` or `clang`)
+are found, and silently continue if Visual Studio activation fails.
+
+`meson setup --vsenv` command line argument can now be used to force Visual Studio
+activation even when other compilers are found. It also make Meson abort with an
+error message when activation fails. This is especially useful for Github Action
+because their Windows images have gcc in their PATH by default.
+
+`--vsenv` is set by default when using `vs` backend.
+
+Only `setup`, `compile`, `dist` and `devenv` subcommands now activate Visual Studio.
+
+## MSVC compiler now assumes UTF-8 source code by default
+
+Every project that uses UTF-8 source files had to add manually `/utf-8` C/C++
+compiler argument for MSVC otherwise they wouldn't work on non-English locale.
+Meson now switched the default to UTF-8 to be more consistent with all other
+compilers.
+
+This can be overridden but using `/source-charset`:
+```meson
+if cc.get_id() == 'msvc'
+  add_project_arguments('/source-charset:.XYZ', language: ['c', 'cpp'])
+endif
+```
+
+See Microsoft documentation for details:
+https://docs.microsoft.com/en-us/cpp/build/reference/source-charset-set-source-character-set.
+
+## Add support for `find_library` in Emscripten
+
+The `find_library` method can be used to find your own JavaScript
+libraries. The limitation is that they must have the file extension
+`.js`. Other library lookups will look up "native" libraries from the
+system like currently. A typical usage would look like this:
+
+```meson
+glue_lib = cc.find_library('gluefuncs.js',
+                           dirs: meson.current_source_dir())
+executable('prog', 'prog.c',
+           dependencies: glue_lib)
+```
+
+## Optional `custom_target()` name
+
+The name argument is now optional and defaults to the basename of the first
+output.
+