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diff --git a/meson/docs/markdown/Release-notes-for-0.50.0.md b/meson/docs/markdown/Release-notes-for-0.50.0.md new file mode 100644 index 000000000..0f7dbb878 --- /dev/null +++ b/meson/docs/markdown/Release-notes-for-0.50.0.md @@ -0,0 +1,350 @@ +--- +title: Release 0.50.0 +short-description: Release notes for 0.50.0 +... + +# New features + +## Added `cmake_module_path` and `cmake_args` to dependency + +The CMake dependency backend can now make use of existing +`Find<name>.cmake` files by setting the `CMAKE_MODULE_PATH` with the +new `dependency()` property `cmake_module_path`. The paths given to +`cmake_module_path` should be relative to the project source +directory. + +Furthermore the property `cmake_args` was added to give CMake +additional parameters. + +## Added PGI compiler support + +Nvidia / PGI C, C++ and Fortran +[no-cost](https://www.pgroup.com/products/community.htm) compilers are +now supported. They have been tested on Linux so far. + + + +## Fortran Coarray + +Fortran 2008 / 2018 coarray support was added via `dependency('coarray')` + +## Libdir defaults to `lib` when cross compiling + +Previously `libdir` defaulted to the value of the build machine such +as `lib/x86_64-linux-gnu`, which is almost always incorrect when cross +compiling. It now defaults to plain `lib` when cross compiling. Native +builds remain unchanged and will point to the current system's library +dir. + +## Native and Cross File Paths and Directories + +A new `[paths]` section has been added to native and cross files. This +can be used to set paths such a prefix and libdir in a persistent way. + +## Add warning_level 0 option + +Adds support for a warning level 0 which does not enable any static +analysis checks from the compiler + +## A builtin target to run clang-format + +If you have `clang-format` installed and there is a `.clang-format` +file in the root of your master project, Meson will generate a run +target called `clang-format` so you can reformat all files with one +command: + +```meson +ninja clang-format +``` + + +## Added `.path()` method to object returned by `python.find_installation()` + +`ExternalProgram` objects as well as the object returned by the +`python3` module provide this method, but the new `python` module did +not. + +## Fix ninja console log from generators with multiple output nodes + +This resolves [issue +#4760](https://github.com/mesonbuild/meson/issues/4760) where a +generator with multiple output nodes printed an empty string to the +console + +## `introspect --buildoptions` can now be used without configured build directory + +It is now possible to run `meson introspect --buildoptions /path/to/meson.build` +without a configured build directory. + +Running `--buildoptions` without a build directory produces the same +output as running it with a freshly configured build directory. + +However, this behavior is not guaranteed if subprojects are +present. Due to internal limitations all subprojects are processed +even if they are never used in a real Meson run. Because of this +options for the subprojects can differ. + +## `include_directories` accepts a string + +The `include_directories` keyword argument now accepts plain strings +rather than an include directory object. Meson will transparently +expand it so that a declaration like this: + +```meson +executable(..., include_directories: 'foo') +``` + +Is equivalent to this: + +```meson +foo_inc = include_directories('foo') +executable(..., include_directories: foo_inc) +``` + +## Fortran submodule support + +Initial support for Fortran `submodule` was added, where the submodule +is in the same or different file than the parent `module`. The +submodule hierarchy specified in the source Fortran code `submodule` +statements are used by Meson to resolve source file dependencies. For +example: + +```fortran +submodule (ancestor:parent) child +``` + + +## Add `subproject_dir` to `--projectinfo` introspection output + +This allows applications interfacing with Meson (such as IDEs) to know +about an overridden subproject directory. + +## Find library with its headers + +The `find_library()` method can now also verify if the library's +headers are found in a single call, using the `has_header()` method +internally. + +```meson +# Aborts if the 'z' library is found but not its header file +zlib = find_library('z', has_headers : 'zlib.h') +# Returns not-found if the 'z' library is found but not its header file +zlib = find_library('z', has_headers : 'zlib.h', required : false) +``` + +Any keyword argument with the `header_` prefix passed to +`find_library()` will be passed to the `has_header()` method with the +prefix removed. + +```meson +libfoo = find_library('foo', + has_headers : ['foo.h', 'bar.h'], + header_prefix : '#include <baz.h>', + header_include_directories : include_directories('.')) +``` + +## NetCDF + +NetCDF support for C, C++ and Fortran is added via pkg-config. + +## Added the Flang compiler + +[Flang](https://github.com/flang-compiler/flang/releases) Fortran +compiler support was added. As with other Fortran compilers, flang is +specified using `FC=flang meson ..` or similar. + +## New `not_found_message` for `dependency()` + +You can now specify a `not_found_message` that will be printed if the +specified dependency was not found. The point is to convert constructs +that look like this: + +```meson +d = dependency('something', required: false) +if not d.found() + message('Will not be able to do something.') +endif +``` + +Into this: + +```meson +d = dependency('something', + required: false, + not_found_message: 'Will not be able to do something.') +``` + +Or constructs like this: + +```meson +d = dependency('something', required: false) +if not d.found() + error('Install something by doing XYZ.') +endif +``` + +into this: + +```meson +d = dependency('something', + not_found_message: 'Install something by doing XYZ.') +``` + +Which works, because the default value of `required` is `true`. + +## Cuda support + +Compiling Cuda source code is now supported, though only with the +Ninja backend. This has been tested only on Linux for now. + +Because NVidia's Cuda compiler does not produce `.d` dependency files, +dependency tracking does not work. + +## `run_command()` accepts `env` kwarg + +You can pass [`environment`](Reference-manual.md#environment-object) +object to [`run_command`](Reference-manual.md#run-command), just +like to `test`: + +```meson +env = environment() +env.set('FOO', 'bar') +run_command('command', 'arg1', 'arg2', env: env) +``` + +## `extract_objects:` accepts `File` arguments + +The `extract_objects` function now supports File objects to tell it +what to extract. Previously, file paths could only be passed as strings. + +## Changed the JSON format of the introspection + +All paths used in the Meson introspection JSON format are now +absolute. This affects the `filename` key in the targets introspection +and the output of `--buildsystem-files`. + +Furthermore, the `filename` and `install_filename` keys in the targets +introspection are now lists of strings with identical length. + +The `--target-files` option is now deprecated, since the same information +can be acquired from the `--tragets` introspection API. + +## Meson file rewriter + +This release adds the functionality to perform some basic modification +on the `meson.build` files from the command line. The currently +supported operations are: + +- For build targets: + - Add/Remove source files + - Add/Remove targets + - Modify a select set of kwargs + - Print some JSON information +- For dependencies: + - Modify a select set of kwargs +- For the project function: + - Modify a select set of kwargs + - Modify the default options list + +For more information see the rewriter documentation. + +## `introspect --scan-dependencies` can now be used to scan for dependencies used in a project + +It is now possible to run `meson introspect --scan-dependencies +/path/to/meson.build` without a configured build directory to scan for +dependencies. + +The output format is as follows: + +```json +[ + { + "name": "The name of the dependency", + "required": true, + "conditional": false, + "has_fallback": false + } +] +``` + +The `required` keyword specifies whether the dependency is marked as +required in the `meson.build` (all dependencies are required by +default). The `conditional` key indicates whether the `dependency()` +function was called inside a conditional block. In a real Meson run +these dependencies might not be used, thus they _may_ not be required, +even if the `required` key is set. The `has_fallback` key just +indicates whether a fallback was directly set in the `dependency()` +function. + +## `introspect --targets` can now be used without configured build directory + +It is now possible to run `meson introspect --targets +/path/to/meson.build` without a configured build directory. + +The generated output is similar to running the introspection with a +build directory. However, there are some key differences: + +- The paths in `filename` now are _relative_ to the future build directory +- The `install_filename` key is completely missing +- There is only one entry in `target_sources`: + - With the language set to `unknown` + - Empty lists for `compiler` and `parameters` and `generated_sources` + - The `sources` list _should_ contain all sources of the target + +There is no guarantee that the sources list in `target_sources` is +correct. There might be differences, due to internal limitations. It +is also not guaranteed that all targets will be listed in the output. +It might even be possible that targets are listed, which won't exist +when Meson is run normally. This can happen if a target is defined +inside an if statement. Use this feature with care. + +## Added option to introspect multiple parameters at once + +Meson introspect can now print the results of multiple introspection +commands in a single call. The results are then printed as a single +JSON object. + +The format for a single command was not changed to keep backward +compatibility. + +Furthermore the option `-a,--all`, `-i,--indent` and +`-f,--force-object-output` were added to print all introspection +information in one go, format the JSON output (the default is still +compact JSON) and force use the new output format, even if only one +introspection command was given. + +A complete introspection dump is also stored in the `meson-info` +directory. This dump will be (re)generated each time meson updates the +configuration of the build directory. + +Additionlly the format of `meson introspect target` was changed: + + - New: the `sources` key. It stores the source files of a target and their compiler parameters. + - New: the `defined_in` key. It stores the Meson file where a target is defined + - New: the `subproject` key. It stores the name of the subproject where a target is defined. + - Added new target types (`jar`, `shared module`). + +## `meson configure` can now print the default options of an unconfigured project + +With this release, it is also possible to get a list of all build +options by invoking `meson configure` with the project source +directory or the path to the root `meson.build`. In this case, Meson +will print the default values of all options. + +## HDF5 + +HDF5 support is added via pkg-config. + +## Added the `meson-info.json` introspection file + +Meson now generates a `meson-info.json` file in the `meson-info` +directory to provide introspection information about the latest Meson +run. This file is updated when the build configuration is changed and +the build files are (re)generated. + +## New kwarg `install:` for `configure_file()` + +Previously when using `configure_file()`, you could install the +outputted file by setting the `install_dir:` keyword argument. Now, +there is an explicit kwarg `install:` to enable/disable it. Omitting +it will maintain the old behaviour. |