docs/markdown/Release-notes-for-0.64.0.md - meson - Git at Google

 ---
 title: Release 0.64.0
 short-description: Release notes for 0.64.0
 ...

 # New features

 ## Add `optimization` `plain` option

 The `optimization` built-in option now accepts `plain` value,
 which will not set any optimization flags. This is now the default
 value of the flag for `buildtype=plain`, which is useful for distros,
 that set the optimization and hardening flags by other means.

 If you are using the value of `get_option('optimization')` in your
 Meson scripts, make sure you are not making assumptions about it,
 such as that the value can be passed to a compiler in `-O` flag.

 ## New languages: `nasm` and `masm`

 When the `nasm` language is added to the project, `.asm` files are
 automatically compiled with NASM. This is only supported for x86 and x86_64 CPU
 family. `yasm` is used as fallback if `nasm` command is not found.

 When the `masm` language is added to the project, `.masm` files are
 automatically compiled with Microsoft's Macro Assembler. This is only supported
 for x86, x86_64, ARM and AARCH64 CPU families.

 Note that GNU Assembly files usually have `.s` or `.S` extension and were already
 built using C compiler such as GCC or CLANG.

 ```meson
 project('test', 'nasm')

 exe = executable('hello', 'hello.asm')
 test('hello', exe)
 ```

 ## Pager and colors for `meson configure` output

 The output of `meson configure`, printing all options, is now more readable by
 automatically using a pager (`less` by default) and colors. The pager used can
 be controlled by setting `PAGER` environment variable, or `--no-pager` command
 line option.

 ## various `install_*` functions no longer handle the sticky bit

 It is not possible to portably grant the sticky bit to a file, and where
 possible, it doesn't do anything. It is not expected that any users are using
 this functionality.

 Variously:
 - on Linux, it has no meaningful effect
 - on Solaris, attempting to set the permission bit is silently ignored by the OS
 - on FreeBSD, attempting to set the permission bit is an error

 Attempting to set this permission bit in the `install_mode:` kwarg to any
 function other than [[install_emptydir]] will now result in a warning, and the
 permission bit being ignored.

 ## `fs.copyfile` to replace `configure_file(copy : true)`

 A new method has been added to the `fs` module, `copyfile`. This method replaces
 `configure_file(copy : true)`, but only copies files. Unlike `configure_file()`
 it runs at build time, and the output name is optional defaulting to the
 filename without paths of the input if unset:

 ```meson
 fs.copyfile('src/file.txt')
 ```
 Will create a file in the current build directory called `file.txt`


 ```meson
 fs.copyfile('file.txt', 'outfile.txt')
 ```
 Will create a copy renamed to `outfile.txt`

 ## Added `update_mime_database` to `gnome.post_install()`

 Applications that install a `.xml` file containing a `mime-type` need to update
 the cache upon installation. Most applications do that using a custom script,
 but it can now be done by Meson directly.

 ## Added preserve_path arg to install_data

 The [[install_data]] function now has an optional argument `preserve_path`
 that allows installing multi-directory data file structures that live
 alongside source code with a single command.

 This is also available in the specialized `py_installation.install_sources`
 method.

 ## BSD support for the `jni` dependency

 This system dependency now supports all BSD systems that Meson currently
 supports, including FreeBSD, NetBSD, OpenBSD, and DragonflyBSD.

 ## Credentials from `~/.netrc` for `https` URLs

 When a subproject is downloaded using an `https://` URL, credentials from
 `~/.netrc` are now used. This avoids hardcoding login and password in plain
 text in the URL itself.

 ## Basic support for oneAPI compilers on Linux and Windows

 To use on Linux:

 ```
 source /opt/intel/oneapi/setvars.sh
 CC=icx CXX=icpx FC=ifx meson setup builddir
 ```

 ## New method to preprocess source files

 Compiler object has a new `preprocess()` method. It is supported by all C/C++
 compilers. It preprocess sources without compiling them.

 The preprocessor will receive the same arguments (include directories, defines,
 etc) as with normal compilation. That includes for example args added with
 `add_project_arguments()`, or on the command line with `-Dc_args=-DFOO`.

 ```meson
 cc = meson.get_compiler('c')
 pp_files = cc.preprocess('foo.c', 'bar.c', output: '@PLAINNAME@')
 exe = executable('app', pp_files)
 ```

 ## python.find_installation() now accepts pure argument

 The default value of `pure:` for `py.install_sources()` and
 `py.get_install_dir()` can now be changed by explicitly passing a `pure:` kwarg
 to `find_installation()`.

 This can be used to ensure that multiple `install_sources()` invocations do not
 forget to specify the kwarg each time.

 ## Generates rust-project.json when there are Rust targets

 This is a format similar to compile_commands.json, but specifically used by the
 official rust LSP, rust-analyzer. It is generated automatically if there are
 Rust targets, and is placed in the build directory.

 ## `summary()` accepts disablers

 Disabler options can be passed to `summary()` as the value to be printed.

 ## Option to allow meson test to fail fast after the first failing testcase

 `meson test --maxfail=1` will now cause all pending or in-progress tests to be
 canceled or interrupted after 1 test is marked as failing. This can be used for
 example to quit a CI run and avoid burning additional time as soon as it is
 known that the overall return status will be failing.

 ## Incremental ThinLTO with `b_thinlto_cache`

 [Incremental ThinLTO](https://clang.llvm.org/docs/ThinLTO.html#incremental) can now be enabled by passing
 `-Db_thinlto_cache=true` during setup. The use of caching speeds up incremental builds significantly while retaining all
 the runtime performance benefits of ThinLTO.

 The cache location defaults to a Meson-managed directory inside the build folder, but can be customized with
 `b_thinlto_cache_dir`.

 ## Update all wraps from WrapDB with `meson wrap update` command

 The command `meson wrap update`, with no extra argument, will now update all wraps
 that comes from WrapDB to the latest version. The extra `--force` argument will
 also replace wraps that do not come from WrapDB if one is available.

 The command `meson subprojects update` will not download new wrap files from
 WrapDB any more.

 ## Added `include_core_only` arg to wayland.scan_xml.

 The `scan_xml` function from the wayland module now has an optional bool
 argument `include_core_only`, so that headers generated by wayland-scanner now
 only include `wayland-client-core.h` instead of `wayland-client.h`.

 ## Automatic fallback using WrapDB

 A new command has been added: `meson wrap update-db`. It downloads the list of
 wraps available in [WrapDB](https://wrapdb.mesonbuild.com) and stores it locally in
 `subprojects/wrapdb.json`. When that file exists and a dependency is not found
 on the system but is available in WrapDB, Meson will automatically download it.
	---
	title: Release 0.64.0
	short-description: Release notes for 0.64.0
	...

	# New features

	## Add `optimization` `plain` option

	The `optimization` built-in option now accepts `plain` value,
	which will not set any optimization flags. This is now the default
	value of the flag for `buildtype=plain`, which is useful for distros,
	that set the optimization and hardening flags by other means.

	If you are using the value of `get_option('optimization')` in your
	Meson scripts, make sure you are not making assumptions about it,
	such as that the value can be passed to a compiler in `-O` flag.

	## New languages: `nasm` and `masm`

	When the `nasm` language is added to the project, `.asm` files are
	automatically compiled with NASM. This is only supported for x86 and x86_64 CPU
	family. `yasm` is used as fallback if `nasm` command is not found.

	When the `masm` language is added to the project, `.masm` files are
	automatically compiled with Microsoft's Macro Assembler. This is only supported
	for x86, x86_64, ARM and AARCH64 CPU families.

	Note that GNU Assembly files usually have `.s` or `.S` extension and were already
	built using C compiler such as GCC or CLANG.

	```meson
	project('test', 'nasm')

	exe = executable('hello', 'hello.asm')
	test('hello', exe)
	```

	## Pager and colors for `meson configure` output

	The output of `meson configure`, printing all options, is now more readable by
	automatically using a pager (`less` by default) and colors. The pager used can
	be controlled by setting `PAGER` environment variable, or `--no-pager` command
	line option.

	## various `install_*` functions no longer handle the sticky bit

	It is not possible to portably grant the sticky bit to a file, and where
	possible, it doesn't do anything. It is not expected that any users are using
	this functionality.

	Variously:
	- on Linux, it has no meaningful effect
	- on Solaris, attempting to set the permission bit is silently ignored by the OS
	- on FreeBSD, attempting to set the permission bit is an error

	Attempting to set this permission bit in the `install_mode:` kwarg to any
	function other than [[install_emptydir]] will now result in a warning, and the
	permission bit being ignored.

	## `fs.copyfile` to replace `configure_file(copy : true)`

	A new method has been added to the `fs` module, `copyfile`. This method replaces
	`configure_file(copy : true)`, but only copies files. Unlike `configure_file()`
	it runs at build time, and the output name is optional defaulting to the
	filename without paths of the input if unset:

	```meson
	fs.copyfile('src/file.txt')
	```
	Will create a file in the current build directory called `file.txt`


	```meson
	fs.copyfile('file.txt', 'outfile.txt')
	```
	Will create a copy renamed to `outfile.txt`

	## Added `update_mime_database` to `gnome.post_install()`

	Applications that install a `.xml` file containing a `mime-type` need to update
	the cache upon installation. Most applications do that using a custom script,
	but it can now be done by Meson directly.

	## Added preserve_path arg to install_data

	The [[install_data]] function now has an optional argument `preserve_path`
	that allows installing multi-directory data file structures that live
	alongside source code with a single command.

	This is also available in the specialized `py_installation.install_sources`
	method.

	## BSD support for the `jni` dependency

	This system dependency now supports all BSD systems that Meson currently
	supports, including FreeBSD, NetBSD, OpenBSD, and DragonflyBSD.

	## Credentials from `~/.netrc` for `https` URLs

	When a subproject is downloaded using an `https://` URL, credentials from
	`~/.netrc` are now used. This avoids hardcoding login and password in plain
	text in the URL itself.

	## Basic support for oneAPI compilers on Linux and Windows

	To use on Linux:

	```
	source /opt/intel/oneapi/setvars.sh
	CC=icx CXX=icpx FC=ifx meson setup builddir
	```

	## New method to preprocess source files

	Compiler object has a new `preprocess()` method. It is supported by all C/C++
	compilers. It preprocess sources without compiling them.

	The preprocessor will receive the same arguments (include directories, defines,
	etc) as with normal compilation. That includes for example args added with
	`add_project_arguments()`, or on the command line with `-Dc_args=-DFOO`.

	```meson
	cc = meson.get_compiler('c')
	pp_files = cc.preprocess('foo.c', 'bar.c', output: '@PLAINNAME@')
	exe = executable('app', pp_files)
	```

	## python.find_installation() now accepts pure argument

	The default value of `pure:` for `py.install_sources()` and
	`py.get_install_dir()` can now be changed by explicitly passing a `pure:` kwarg
	to `find_installation()`.

	This can be used to ensure that multiple `install_sources()` invocations do not
	forget to specify the kwarg each time.

	## Generates rust-project.json when there are Rust targets

	This is a format similar to compile_commands.json, but specifically used by the
	official rust LSP, rust-analyzer. It is generated automatically if there are
	Rust targets, and is placed in the build directory.

	## `summary()` accepts disablers

	Disabler options can be passed to `summary()` as the value to be printed.

	## Option to allow meson test to fail fast after the first failing testcase

	`meson test --maxfail=1` will now cause all pending or in-progress tests to be
	canceled or interrupted after 1 test is marked as failing. This can be used for
	example to quit a CI run and avoid burning additional time as soon as it is
	known that the overall return status will be failing.

	## Incremental ThinLTO with `b_thinlto_cache`

	[Incremental ThinLTO](https://clang.llvm.org/docs/ThinLTO.html#incremental) can now be enabled by passing
	`-Db_thinlto_cache=true` during setup. The use of caching speeds up incremental builds significantly while retaining all
	the runtime performance benefits of ThinLTO.

	The cache location defaults to a Meson-managed directory inside the build folder, but can be customized with
	`b_thinlto_cache_dir`.

	## Update all wraps from WrapDB with `meson wrap update` command

	The command `meson wrap update`, with no extra argument, will now update all wraps
	that comes from WrapDB to the latest version. The extra `--force` argument will
	also replace wraps that do not come from WrapDB if one is available.

	The command `meson subprojects update` will not download new wrap files from
	WrapDB any more.

	## Added `include_core_only` arg to wayland.scan_xml.

	The `scan_xml` function from the wayland module now has an optional bool
	argument `include_core_only`, so that headers generated by wayland-scanner now
	only include `wayland-client-core.h` instead of `wayland-client.h`.

	## Automatic fallback using WrapDB

	A new command has been added: `meson wrap update-db`. It downloads the list of
	wraps available in [WrapDB](https://wrapdb.mesonbuild.com) and stores it locally in
	`subprojects/wrapdb.json`. When that file exists and a dependency is not found
	on the system but is available in WrapDB, Meson will automatically download it.