This is what Autoconf already does for us, so just do this. Avoids
people making typos while adding header or function checks. Because we
use a config.h.meson, such typos won't even be noticed.
Also, starting from Meson 0.36.0, the XCode 8 workaround that we use for
clock_gettime is no longer needed.
This brings us up-to-speed with the latest compatibility code from upstream
check git. For completeness, we do all the checks that upstream check does, but
we skip the snprintf/vsnprintf code because it's not straightforward (involves
running code and that is bad for cross-compilation) and not necessary for the
platforms we support anyway.
If someone really wants this, they can uncomment this and copy the relevant
checks from the check git repository.
https://bugzilla.gnome.org/show_bug.cgi?id=775870
clock_gettime was also added for iOS 10.0, so don't use it if we're
targetting an older version. That would've caused the symbol to not be
found at runtime on older devices.
Just use the default c_std used by the compiler. With GCC on Linux this
is gnu89.
Tons of errors related to time.h, signal.h, etc when using c99:
FAILED: libs/gst/check/libcheck/check@sta/check_run.c.o
cc '-Ilibs/gst/check/libcheck/check@sta' '-fdiagnostics-color=always' '-I../libs/gst/check/libcheck' '-Ilibs/gst/check/libcheck' '-I.' '-I../.' '-Ilibs/gst/check/libcheck/..' '-I../libs/gst/check/libcheck/..' '-pipe' '-Wall' '-Winvalid-pch' '-std=c99' '-DHAVE_CONFIG_H' '-fPIC' '-O2' '-g' '-fPIC' '-MMD' '-MQ' 'libs/gst/check/libcheck/check@sta/check_run.c.o' '-MF' 'libs/gst/check/libcheck/check@sta/check_run.c.o.d' -o 'libs/gst/check/libcheck/check@sta/check_run.c.o' -c ../libs/gst/check/libcheck/check_run.c
In file included from ../libs/gst/check/libcheck/check_run.c:21:0:
../libs/gst/check/libcheck/libcompat.h:167:18: warning: ‘struct itimerspec’ declared inside parameter list will not be visible outside of this definition or declaration
const struct itimerspec *new_value, struct itimerspec *old_value);
^~~~~~~~~~
../libs/gst/check/libcheck/check_run.c:98:25: error: array type has incomplete element type ‘struct sigaction’
static struct sigaction old_action[3];
^~~~~~~~~~
../libs/gst/check/libcheck/check_run.c:99:25: error: array type has incomplete element type ‘struct sigaction’
static struct sigaction new_action[3];
^~~~~~~~~~
[...]
ninja: build stopped: subcommand failed.
The change was originally made because gnu99 was causing issues on OS X.
With XCode 8, clock_gettime will be incorrectly detected as being
available regardless of what OS X version we're targetting because the
symbol is available in the .tbd library as a weak symbol.
See: https://github.com/Homebrew/homebrew-core/issues/3727#issue-170086273
It's only starting from macOS 10.12 that clock_gettime is actually
available, so we can unconditionally disable it when targetting older
versions. We cannot simply do AC_CHECK_FUNCS with -Wl,-no_weak_imports
because the autoconf check does its own prototype declaration that
doesn't trigger that compiler flag.
https://bugzilla.gnome.org/show_bug.cgi?id=772451
Earlier we were only using __declspec(dllexport/import) when we were
built with MSVC because when built with MinGW and linking with MinGW we
don't need it (and we get linker errors because of it).
However, when we're built with MinGW and someone wants to link to us
with MSVC, we still need the prototypes to have __declspec(dllimport)
since MSVC cannot do auto-import like GCC can.
https://bugzilla.gnome.org/show_bug.cgi?id=771029
We only use GST_EXPORT consistently when building with MSVC by using the
visual studio definitions files (win32/common/*.def), so always disable
it when building with Autotools and only enable it with Meson when
building with MSVC.
This allows you to use MinGW to link to a GStreamer built with MSVC and
get the correct function prototypes to find functions and variables in
DLLs.
https://github.com/mesonbuild/meson
With contributions from:
Tim-Philipp Müller <tim@centricular.com>
Mathieu Duponchelle <mathieu.duponchelle@opencreed.com>
Jussi Pakkanen <jpakkane@gmail.com> (original port)
Highlights of the features provided are:
* Faster builds on Linux (~40-50% faster)
* The ability to build with MSVC on Windows
* Generate Visual Studio project files
* Generate XCode project files
* Much faster builds on Windows (on-par with Linux)
* Seriously fast configure and building on embedded
... and many more. For more details see:
http://blog.nirbheek.in/2016/05/gstreamer-and-meson-new-hope.htmlhttp://blog.nirbheek.in/2016/07/building-and-developing-gstreamer-using.html
Building with Meson should work on both Linux and Windows, but may
need a few more tweaks on other operating systems.
