<s>
Meson	B-Application
(	O
)	O
is	O
a	O
software	B-Application
tool	I-Application
for	O
automating	B-Application
the	I-Application
building	I-Application
(	O
compiling	O
)	O
of	O
software	O
.	O
</s>
<s>
The	O
overall	O
goal	O
for	O
Meson	B-Application
is	O
to	O
promote	O
programmer	O
productivity	O
.	O
</s>
<s>
Meson	B-Application
is	O
free	B-License
and	I-License
open-source	I-License
software	I-License
written	O
in	O
Python	B-Language
,	O
under	O
the	O
Apache	B-Application
License	I-Application
2.0	I-Application
.	O
</s>
<s>
Being	O
written	O
in	O
Python	B-Language
,	O
Meson	B-Application
runs	O
on	O
Unix-like	O
operating	O
systems	O
,	O
including	O
macOS	B-Application
,	O
as	O
well	O
as	O
Microsoft	B-Application
Windows	I-Application
and	O
on	O
other	O
operating	O
systems	O
.	O
</s>
<s>
Meson	B-Application
supports	O
the	O
C	B-Language
,	O
C++	B-Language
,	O
CUDA	B-Architecture
,	O
D	B-Application
,	O
Objective-C	B-Language
,	O
Fortran	B-Application
,	O
Java	B-Language
,	O
C#	B-Application
,	O
Rust	B-Application
,	O
and	O
Vala	B-Language
languages	I-Language
,	O
and	O
has	O
a	O
mechanism	O
for	O
handling	O
dependencies	O
called	O
Wrap	O
.	O
</s>
<s>
Meson	B-Application
supports	O
GNU	B-Application
Compiler	I-Application
Collection	I-Application
,	O
Clang	B-Application
,	O
Microsoft	B-Application
Visual	I-Application
C++	I-Application
and	O
other	O
compilers	O
,	O
including	O
non-traditional	O
compilers	O
such	O
as	O
Emscripten	B-Language
and	O
Cython	B-Application
.	O
</s>
<s>
The	O
project	O
uses	O
ninja	B-Application
as	O
the	O
primary	O
backend	O
buildsystem	O
,	O
but	O
can	O
also	O
use	O
Microsoft	B-Application
Visual	I-Application
Studio	I-Application
or	O
Xcode	B-Operating_System
backends	O
.	O
</s>
<s>
The	O
syntax	O
of	O
Meson	B-Application
's	O
build	O
description	O
files	O
(	O
the	O
Meson	B-Application
language	O
)	O
borrows	O
from	O
Python	B-Language
,	O
but	O
is	O
not	O
Python	B-Language
:	O
It	O
is	O
designed	O
such	O
that	O
it	O
can	O
be	O
reimplemented	O
in	O
any	O
other	O
language	O
;	O
for	O
example	O
,	O
muon	O
is	O
a	O
C	B-Language
implementation	O
and	O
Meson++	O
is	O
a	O
C++	B-Language
implementation	O
–	O
the	O
dependency	O
on	O
Python	B-Language
is	O
an	O
implementation	O
detail	O
.	O
</s>
<s>
The	O
Meson	B-Application
language	O
is	O
intentionally	O
not	O
Turing	B-Algorithm
complete	I-Algorithm
,	O
and	O
can	O
therefore	O
not	O
express	O
an	O
arbitrary	O
program	O
.	O
</s>
<s>
The	O
Meson	B-Application
language	O
is	O
strongly	O
typed	O
,	O
such	O
that	O
builtin	O
types	O
like	O
library	O
,	O
executable	O
,	O
string	O
,	O
and	O
lists	O
thereof	O
,	O
are	O
non-interchangeable	O
.	O
</s>
<s>
Like	O
Ninja	B-Application
,	O
Meson	B-Application
does	O
not	O
support	O
globbing	B-Language
of	O
source	O
files	O
.	O
</s>
<s>
CMake	O
supports	O
globbing	B-Language
,	O
but	O
recommends	O
against	O
it	O
for	O
the	O
same	O
reason	O
.	O
</s>
<s>
Meson	B-Application
uses	O
ccache	B-Application
automatically	O
if	O
installed	O
.	O
</s>
<s>
It	O
also	O
detects	O
changes	O
to	O
symbol	B-Application
tables	I-Application
of	O
shared	O
libraries	O
to	O
skip	O
relinking	O
executables	O
against	O
the	O
library	O
when	O
there	O
are	O
no	O
ABI	O
changes	O
.	O
</s>
<s>
Precompiled	B-Language
headers	I-Language
are	O
supported	O
,	O
but	O
requires	O
configuration	O
.	O
</s>
<s>
speed	O
feature	O
Meson	B-Application
CMake	O
Make	O
Prohibits	O
stale	O
builds	O
(	O
partial	O
rebuild	O
against	O
input	O
change	O
)	O
(	O
unless	O
there	O
are	O
bugs	O
)	O
The	O
target	O
that	O
runs	O
tests	O
depends	O
on	O
the	O
tests	O
being	O
built	O
(	O
e.g.	O
</s>
<s>
A	O
stated	O
goal	O
of	O
Meson	B-Application
is	O
to	O
facilitate	O
modern	O
development	O
practices	O
.	O
</s>
<s>
As	O
such	O
,	O
Meson	B-Application
knows	O
how	O
to	O
do	O
unity	B-Language
builds	I-Language
,	O
build	O
with	O
test	B-Application
coverage	I-Application
,	O
link	O
time	O
optimization	O
etc	O
without	O
the	O
programmer	O
having	O
to	O
write	O
support	O
for	O
this	O
.	O
</s>
<s>
Meson	B-Application
can	O
automatically	O
find	O
and	O
use	O
external	O
dependencies	O
via	O
pkg-config	B-Application
,	O
CMake	O
,	O
and	O
project-specific	O
lookups	O
,	O
but	O
this	O
only	O
finds	O
installed	O
dependencies	O
,	O
which	O
Meson	B-Application
can	O
not	O
do	O
anything	O
about	O
.	O
</s>
<s>
Alternatively	O
,	O
or	O
as	O
a	O
fallback	O
,	O
a	O
dependency	O
can	O
be	O
provided	O
as	O
a	O
subproject	O
–	O
a	O
Meson	B-Application
project	O
within	O
another	O
,	O
either	O
contained	O
or	O
as	O
a	O
download	O
link	O
,	O
possibly	O
with	O
patches	O
.	O
</s>
<s>
This	O
lets	O
Meson	B-Application
resolve	O
dependency	B-Protocol
hell	I-Protocol
for	O
the	O
convenience	O
of	O
casual	O
users	O
who	O
want	O
to	O
compile	O
the	O
project	O
,	O
but	O
may	O
contribute	O
to	O
software	O
bloat	O
if	O
a	O
common	O
installed	O
dependency	O
could	O
have	O
been	O
used	O
instead	O
.	O
</s>
<s>
The	O
mode	O
favored	O
by	O
Linux	B-Application
packagers	I-Application
is	O
therefore	O
fallback	O
.	O
</s>
<s>
Meson	B-Application
supports	O
Meson	B-Application
and	O
CMake	O
subprojects	O
.	O
</s>
<s>
A	O
Meson	B-Application
build	O
file	O
may	O
also	O
refer	O
to	O
the	O
WrapDB	O
service	O
.	O
</s>
<s>
Cross	O
compilation	O
requires	O
extra	O
configuration	O
,	O
which	O
Meson	B-Application
supports	O
in	O
the	O
form	O
of	O
a	O
separate	O
cross	O
file	O
,	O
which	O
can	O
be	O
external	O
to	O
the	O
Meson	B-Application
project	O
.	O
</s>
<s>
GNOME	B-Application
has	O
made	O
it	O
a	O
goal	O
to	O
port	O
its	O
projects	O
to	O
Meson	B-Application
.	O
</s>
<s>
As	O
of	O
late	O
2017	O
,	O
GNOME	B-Language
Shell	I-Language
itself	O
exclusively	O
requires	O
Meson	B-Application
after	O
abandoning	O
Autotools	O
,	O
and	O
central	O
components	O
like	O
GTK+	B-Application
,	O
Clutter-GTK	B-Language
,	O
GLib	B-Language
and	O
GStreamer	B-Language
can	O
be	O
built	O
with	O
Meson	B-Application
.	O
</s>
<s>
Many	O
freedesktop.org	B-Application
projects	O
have	O
switched	O
to	O
Meson	B-Application
.	O
</s>
<s>
Systemd	B-Application
relies	O
on	O
Meson	B-Application
since	O
dropping	O
Autotools	O
in	O
version	O
234	O
,	O
and	O
also	O
X.Org	B-Operating_System
and	O
Mesa	B-Application
were	O
ported	O
to	O
Meson	B-Application
.	O
</s>
<s>
Meson	B-Application
's	O
support	O
for	O
Fortran	B-Application
and	O
Cython	B-Application
was	O
improved	O
to	O
help	O
various	O
scientific	O
projects	O
in	O
their	O
switch	O
from	O
to	O
Meson	B-Application
,	O
for	O
example	O
SciPy	B-Application
.	O
</s>
<s>
Meson	B-Application
can	O
also	O
be	O
used	O
as	O
a	O
PEP517	O
backend	O
to	O
build	O
Python	B-Language
wheels	O
,	O
via	O
the	O
package	O
.	O
</s>
<s>
Other	O
notable	O
projects	O
using	O
Meson	B-Application
include	O
QEMU	B-Application
and	O
Libvirt	B-Language
;	O
the	O
Meson	B-Application
homepage	O
lists	O
further	O
projects	O
using	O
Meson	B-Application
.	O
</s>
