New features

A new module for filesystem operations

The new fs module can be used to examine the contents of the current file system.

fs = import('fs')
assert(fs.exists('important_file'),
       'The important file is missing.')

meson dist --include-subprojects

meson dist command line now gained --include-subprojects command line option. When enabled, the source tree of all subprojects used by the current build will also be included in the final tarball. This is useful to distribute self contained tarball that can be built offline (i.e. --wrap-mode=nodownload).

Added new Meson templates for Dlang, Rust, Objective-C

Meson now ships with predefined project templates for Dlang, Fortran, Rust, Objective-C, and by passing the associated flags d, fortran, rust, objc to meson init --language.

Add a new summary() function

A new function summary() has been added to summarize build configuration at the end of the build process.

Example:

project('My Project', version : '1.0')
summary({'bindir': get_option('bindir'),
         'libdir': get_option('libdir'),
         'datadir': get_option('datadir'),
        }, section: 'Directories')
summary({'Some boolean': false,
         'Another boolean': true,
         'Some string': 'Hello World',
         'A list': ['string', 1, true],
        }, section: 'Configuration')

Output:

My Project 1.0

  Directories
             prefix: /opt/gnome
             bindir: bin
             libdir: lib/x86_64-linux-gnu
            datadir: share

  Configuration
       Some boolean: False
    Another boolean: True
        Some string: Hello World
             A list: string
                     1
                     True

Generic Overrider for Dynamic Linker selection

Previous to meson 0.52.0 you set the dynamic linker using compiler specific flags passed via language flags and hoped things worked out. In meson 0.52.0 meson started detecting the linker and making intelligent decisions about using it. Unfortunately this broke choosing a non-default linker.

Now there is a generic mechanism for doing this. In 0.53.0, you can use the LD environment variable. In 0.53.1 this was changed to <compiler_variable>_LD, such as CC_LD, CXX_LD, D_LD, etc due to regressions. The usual meson environment variable rules apply. Alternatively, you can add the following to a cross or native file:

In 0.53.0:

[binaries]
ld = 'gold'

In 0.53.1 or newer:

[binaries]
c = 'gcc'
c_ld = 'gold'
[binaries]
c = 'clang'
c_ld = 'lld'

And meson will select the linker if possible.

fortran_std option

new in 0.53.0 Akin to the c_std and cpp_std options, the fortran_std option sets Fortran compilers to warn or error on non-Fortran standard code. Only the Gfortran and Intel Fortran compilers have support for this option. Other Fortran compilers ignore the fortran_std option.

Supported values for fortran_std include:

  • legacy for non-conforming code--this is especially important for Gfortran, which by default errors on old non-compliant Fortran code
  • f95 for Fortran 95 compliant code.
  • f2003 for Fortran 2003 compliant code.
  • f2008 for Fortran 2008 compliant code.
  • f2018 for Fortran 2018 compliant code.

python.dependency() embed kwarg

Added the embed kwarg to the python module dependency function to select the python library that can be used to embed python into an application.

Scalapack

added in 0.53.0:

scalapack = dependency('scalapack')

Historically and through today, typical Scalapack setups have broken and incomplete pkg-config or FindScalapack.cmake. Meson handles finding Scalapack on setups including:

  • Linux: Intel MKL or OpenMPI + Netlib
  • MacOS: Intel MKL or OpenMPI + Netlib
  • Windows: Intel MKL (OpenMPI not available on Windows)

Search directories for find_program()

It is now possible to give a list of absolute paths where find_program() should also search, using the dirs keyword argument.

For example on Linux /sbin and /usr/sbin are not always in the $PATH:

prog = find_program('mytool', dirs : ['/usr/sbin', '/sbin'])

Source tags targets

When the respective tools are available, 'ctags', 'TAGS' and 'cscope' targets will be generated by Meson, unless you have defined your own.

Dictionary entry using string variable as key

Keys can now be any expression evaluating to a string value, not limited to string literals any more.

d = {'a' + 'b' : 42}
k = 'cd'
d += {k : 43}

Improved CMake subprojects support

With this release even more CMake projects are supported via CMake subprojects due to these internal improvements:

  • Use the CMake file API for CMake >=3.14
  • Handle the explicit dependencies via add_dependency
  • Basic support for add_custom_target
  • Improved add_custom_command support
  • Object library support on Windows

compiler.get_linker_id()

since 0.53.0, compiler.get_linker_id() allows retrieving a lowercase name for the linker. Since each compiler family can typically use a variety of linkers depending on operating system, this helps users define logic for corner cases not otherwise easily handled.

CUDA dependency

Native support for compiling and linking against the CUDA Toolkit using the dependency function:

project('CUDA test', 'cpp', meson_version: '>= 0.53.0')
exe = executable('prog', 'prog.cc', dependencies: dependency('cuda'))

See the CUDA dependency for more information.

Added global option to disable C++ RTTI

The new boolean option is called cpp_rtti.

Introspection API changes

dependencies (--dependencies, intro-dependencies.json):

  • added the version key

scanning dependencies (--scan-dependencies):

  • added the version key containing the required dependency version

tests and benchmarks (--tests, --benchmarks, intro-tests.json, intro-benchmarks.json):

  • added the protocol key

The results of the search are