There is no standard mechanism for detecting endianess. Doing it at
compile time in a portable way is probably hard. Doing it properly
with a configure check is probably hard too. Using the endian
definitions in <sys/types.h> (usually includes <endian.h>, which is
not available everywhere) works under circumstances, but the previous
commit broke it on OSX.
Ideally all code should be endian dependent, but that is not possible
due to the dependencies (such as FFmpeg, some video output APIs, some
audio output APIs).
Create a header osdep/endian.h, which contains various fallbacks.
Note that the last fallback uses libavutil; however, it's not clear
whether AV_HAVE_BIGENDIAN is a public symbol, or whether including
<libavutil/bswap.h> really makes it visible. And in fact we don't want
to pollute the namespace with libavutil definitions either. Thus it's
only the last fallback.
_GNU_SOURCE defines the kitchen sink, and also prefers glibc definitions
where glibc and POSIX conflict. Even though POSIX is worth less than
toilet paper, we still prefer the POSIX definitions.
rar.c needs asprintf(), which is _GNU_SOURCE-only. So we define
_GNU_SOURCE too specifically for this file.
These were in the old configure script too.
Two flags are explicitly tested, because I have no idea how widespread
support for them is, and testing them is just easier than trying to look
them up in various gcc/clang manuals. There are people using gcc 4.2
out there, so some caution is warranted.
-Wempty-body is not available on all gcc versions but we were using it
unconditionally. Also remove the usage from the clang case. clang still
defines `__GNUC__` so it still gets all the gcc specific flags.
This should fix the build on systems with older gcc versions like OpenBSD which
still comes bundled with gcc 4.2 for license issues.
Not needed anymore. I'm not opposed to having asm, but inline asm is too
much of a pain, and it was planned long ago to eventually get rid fo all
inline asm uses.
For the note, the inline asm use that was removed with the previous
commits was almost worthless. It was confined to video filters, and most
video filtering is now done with libavfilter. Some mpv filters (like
vf_pullup) actually redirect to libavfilter if possible.
If asm is added in the future, it should happen in the form of external
files.
Cygwin's libc (newlib) doesn't obey a lot of unix feature test macros,
including _GNU_SOURCE; as a result, a lot of functions and defines get
masked out -- important defines such as M_PI and strcasecmp. Work around
it by undefining __STRICT_ANSI__ on cygwin systems.
This will still cause compilation issues on any non-cygwin system that
uses newlib, but hopefully nobody does that, or if they do, they will
find this commit message and know to add -U__STRICT_ANSI__ to their
CFLAGS. Hopefully.
This fixes a weird bug with aspect ratio handling. It has to do with
float handling: with -std=gnu99, gcc implicitly enables broken non-
standard semantics giving float variables excess precision. This can for
example make this fail in theory: "float a = 0.1; assert(a == a);"
While standard C allows excess precision _within_ expressions, it
requires truncation when storing float values in variables of types
"float" or "double". The "gnu99" mode breaks this. It can be unbroken by
using "c99", or by specifying -fexcess-precision=standard. The former
seems less likely to break compilers other than modern gcc. Note that
-ffloat-store would also fix this, but also makes float expressions less
efficient and less precise for no reason.
The code that mistakenly fails because of this is dec_video.c line 393.
It caused the container aspect to be ignored in some or all situations,
depending how the compiler optimizes. For example, on gcc-4.6 with -Os,
the aspect is always ignored.
In future, we should probably just get rid of storing aspects as floats.
This is necessary to start mpv without forcing a console window,
but also breaks console usability. A workaround is to call mpv
from a wrapper process that uses the console subsystem and helps
redirecting the standard streams and WriteConsole output to where
they belong.
This commit adds a new build system based on waf. configure and Makefile
are deprecated effective immediately and someday in the future they will be
removed (they are still available by running ./old-configure).
You can find how the choice for waf came to be in `DOCS/waf-buildsystem.rst`.
TL;DR: we couldn't get the same level of abstraction and customization with
other build systems we tried (CMake and autotools).
For guidance on how to build the software now, take a look at README.md
and the cross compilation guide.
CREDITS:
This is a squash of ~250 commits. Some of them are not by me, so here is the
deserved attribution:
- @wm4 contributed some Windows fixes, renamed configure to old-configure
and contributed to the bootstrap script. Also, GNU/Linux testing.
- @lachs0r contributed some Windows fixes and the bootstrap script.
- @Nikoli contributed a lot of testing and discovered many bugs.
- @CrimsonVoid contributed changes to the bootstrap script.
wm4
Alessandro Ghedini
Stefano Pigozzi
Diogo Franco (Kovensky)
Martin Herkt