Directly loads AviSynth through LoadLibrary instead of relying on
Video for Windows, and supports using AvxSynth (via dlopen) to
open scripts on Linux and OS X.
Error messages from AviSynth/AvxSynth are now reported through
av_log and exit, rather than the traditional behavior of generating
an error video that the user would need to watch to diagnose.
The main rewrite was authored by d s <avxsynth.testing@gmail.com>
from the AvxSynth team, with additional contributions by
Oka Motofumi <chikuzen.mo@gmail.com>
Stephen Hutchinson <qyot27@gmail.com>
Diego Biurrun <diego@biurrun.de>
Anton Khirnov <anton@khirnov.net>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Certain instrumentation addons leads to a false positive in configure
and link failures at the end of the build phase.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
This will check if -wN '..@*' is available and fall back on -x if not;
when none are available, do not run strip at all to prevent removing
functions that might be actually needed.
Msys is unable to convert unix style absolute paths to windows style
paths when combined with certain multichar MSVC options such as
-Fo<file>. We used to work around this issue by passing them as two
separate parameters separated by a space to c99wrap, which then mapped
them back to the actual parameter format that MSVC uses.
The only paths that actually are an issue are absolute unix style
paths, and the only place such absolute paths are used with the output
arguments (-Fo, -Fe, -Fi, -out:) are for the temp files within configure.
By setting TMPDIR to . for msvc/icl builds, we never need to use
absolute unix style paths for the file output, and we can use the
actual proper form of the file output parameters. This avoids requiring
the c99wrap wrapper for remapping the parameters for cases where the
c99 converter isn't invoked at all (MSVC2013 and ICL).
Signed-off-by: Martin Storsjö <martin@martin.st>
ICL doesn't return an error on unknown parameters, and will
always pass the symver_gnu_asm test, and since Windows
never has symbol versioning, just always disable it.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
On some platforms (such as msys), symlinks are (poorly) emulated
by simply creating a copy of the file.
This means that when building out of tree, the build tree gets
a copy of the original makefile, which can lead to unintuitive
build errors when the original makefile gets updated later.
Instead simply create a stub makefile which includes the real
one.
Signed-off-by: Martin Storsjö <martin@martin.st>
Originally written by Ronald S. Bultje <rsbultje@gmail.com> and
Clément Bœsch <u@pkh.me>
Further contributions by:
Anton Khirnov <anton@khirnov.net>
Diego Biurrun <diego@biurrun.de>
Luca Barbato <lu_zero@gentoo.org>
Martin Storsjö <martin@martin.st>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
MSVC does support enough of C99 to work without the converter since
the 2013 version. Try to detect which version of the compiler in
the path needs to run the C99 converter or not. When the converter
is omitted, compilation time is reduced quite drastically.
Prior to this, users could still use --cc="c99conv -noconv cl"
when running MSVC 2013 to achieve the same.
This checks the version number instead of doing a normal compile
test, since this check needs to be done earlier in configure, before
the normal compile test helpers are usable.
Signed-off-by: Martin Storsjö <martin@martin.st>
As another example of bizarre compiler behavior clang groks the
-Wmaybe-uninitialized option, but not -Wno-maybe-uninitialized
and spews a warning for every file that gets compiled.
For some weird reason gcc does not check if the -Wno disabling variants
of warning flags match existing warning flags. Instead it swallows them
silently. That is, unless other warning or error messages are generated,
because then - for some even more bizarre reason - a complaint about the
unknown disable warning flag is issued along with the error or warning
message.
Thus to check for the availability of a warning disabling option, one
needs to check for the enabling variant instead and then add the
disabling variant to CFLAGS.
Initially written by Guillaume Martres <smarter@ubuntu.com> as a GSoC
project. Further contributions by the OpenHEVC project and other
developers, namely:
Mickaël Raulet <mraulet@insa-rennes.fr>
Seppo Tomperi <seppo.tomperi@vtt.fi>
Gildas Cocherel <gildas.cocherel@laposte.net>
Khaled Jerbi <khaled_jerbi@yahoo.fr>
Wassim Hamidouche <wassim.hamidouche@insa-rennes.fr>
Vittorio Giovara <vittorio.giovara@gmail.com>
Jan Ekström <jeebjp@gmail.com>
Anton Khirnov <anton@khirnov.net>
Martin Storsjö <martin@martin.st>
Luca Barbato <lu_zero@gentoo.org>
Yusuke Nakamura <muken.the.vfrmaniac@gmail.com>
Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Diego Biurrun <diego@biurrun.de>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
F4V is Adobe's mp4/iso media variant, with the most significant
addition/change being supporting other flash codecs than just
aac/h264.
Signed-off-by: Martin Storsjö <martin@martin.st>
This is in preparation for removing a .rodata kludge
which was only required for older YASM versions.
The movbe instruction was introduced in 0.8.0, which already
had AVX, which was introduced in 0.7.0, and NASM introduced
movbe in 2.0.3, which is the same version which introduced
AVX support.
Also, make the failure message more accurate.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
The implementation of 25cb0c1a involves lots of spurious labels.
The effect of keeping those labels around is making debugging harder.
Those labels are meaningless, and complicate the disassembly. Also,
gdb can't tell the difference between them and function entry points.
This new strip command is irrelevant to any usage of Libav that would
have used the old fully stripped version, because the old one was for
non-debug use.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Qansi-alias worked on 12.x, then caused miscompilation on 13.x, but now
works again passing all FATE tests for icl version 14.
Signed-off-by: Diego Biurrun <diego@biurrun.de>
Prior to this on msvc/icl there was no handling of deprecated functions
and the deprecated warning was disabled.
After enabling there are a number of warnings relating to the CRT and
the use of the non-secure versions of several functions. Defining
_CRT_SECURE_NO_WARNINGS silences these warnings.
Signed-off-by: Martin Storsjö <martin@martin.st>
The i686 feature really is a CPU feature and should be handled as such.
The cpunop dependency on i686 should be expressed with a standard _deps
declaration instead of a manual test.
The hls muxer itself doesn't have any direct (object file level)
dependencies on mpegtsenc.o, and including that object file
directly doesn't ensure that it is registered so that the muxer
actually is accessible.
Signed-off-by: Martin Storsjö <martin@martin.st>
There is no record of this ever being used at all, anywhere,
since the feature was added in 2effd27446.
This gets rid of extra linker tricks just to support a feature
that isn't used, simplifying portability to other platforms.
Signed-off-by: Martin Storsjö <martin@martin.st>
Use this for enabling the ppc timer.h implementation only on
assemblers that support labels in the inline assembly.
Signed-off-by: Martin Storsjö <martin@martin.st>
Because O1 or O2 are required to build libav with msvc/icl, this must be
explicitly set instead of just omitting Oy.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
It is implied by O1 or O2, both of which are required to build libav
with msvc/icl. Silences warnings when targeting x64 with icl.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
This avoids warnings about this option not having any effect on
this platform.
We still want to enable the pic configure item for these platforms
(if detected via the compiler builtin define __PIC__) to get proper
inline assembly workarounds.
Signed-off-by: Martin Storsjö <martin@martin.st>
This reverts e08c946c6 and 05165c2f7a. The actual intention of
e08c946c6 was to fix shared library builds for arm/win32, which
can also be accomplished in other ways.
Disabling pic on those platforms broke inline assembly on cygwin/64
(since some inline assembly requires knowing whether we are building
as PIC or not), and might also break inline assembly on other
compilers on windows.
As a side-effect, this unfortunately brings back all the warnings
about PIC not having any effect on that platform.
Signed-off-by: Martin Storsjö <martin@martin.st>
The object file format doesn't support PIC loads in ARM assembly,
there are no relocation types in PE/COFF that correspond to
BFD_RELOC_32_PCREL (R_ARM_REL32 in ELF).
Signed-off-by: Martin Storsjö <martin@martin.st>
Allows for easier handling of flags that may be specific to icl or msvc.
Furthermore, simplify the handling of warnings and remarks thanks to
icl's support of -Wall on Windows.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
The modern MSVC for ARM always builds for thumb, and it can't be
disabled.
Also just use the default arch instead of trying to map the -march
parameter to MSVC's -arch parameter (which only takes the values
ARMv7VE and VFPv4).
Signed-off-by: Martin Storsjö <martin@martin.st>
Initial support for the ICL compiler on windows. Requires a new
c99wrap with ICL support (1.0.2+).
Currently not much different speed wise compared to msvc. In the
future with a few changes it can be made to support the inline asm.
This would be the primary reason for using it.
Passed all fate tests, versions tested:
13.1.1.171 (2013 Update 3) x86 and x64
12.1.5.344 (2011 Update 11) x86 and x64
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Change the check_exec_crash test to use a function pointer instead of
simply calling the function. The EBP availability test will crash when
compiled with ICL likely due to compiler optimization shenanigans.
Originally the check_exec_crash code was moved out of main to fix a
problem with gcc's treatment of non-leaf main on x86_32. Libav already
moved the code out of main but the addition of the function pointer will
prevent any inlining which fixes the remaining problem.
A function pointer is used since it is compiler agnostic (as opposed to
say __attribute__ ((noinline)) which would only work with gcc compatible
compilers).
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
MSVC 2010 (or more precisely, Windows SDK 7.0 which comes with MSVC
2010) sets _WIN32_WINNT to the constant for Windows 7 if nothing is
set. This could lead to the libav configure script detecting and
using functions only present in Windows 7 or newer, which in most
cases isn't desired. If the caller explicitly wants this, the caller
can add the _WIN32_WINNT define via --extra-cflags, setting the desired
version.
Signed-off-by: Martin Storsjö <martin@martin.st>
With the parameter --toolchain valgrind-massif, the configure
script sets reasonable defaults that can be overridden as explained
in the documentation.
This makes it consistent with the msvc builds which automatically set
the DEP and ASLR flags by default. There really is no good reason why
they shouldn't be set.
The fact that binutils does not set them on by default boggles the mind.
Signed-off-by: Martin Storsjö <martin@martin.st>
If this is explicitly disabled for win32/mingw, it should also
be disabled for cygwin, for consistency and for the same reasons
as for win32/mingw.
Signed-off-by: Martin Storsjö <martin@martin.st>
These platforms do not have any notion of PIC. On some compilers,
enabling pic produces a number of warnings.
This avoids trying to produce PIC loads in the ARM assembly - there
are no relocation types in PE/COFF that correspond to
BFD_RELOC_32_PCREL (R_ARM_REL32 in ELF).
As a side-effect, this avoids enabling PIC on mingw64, getting rid
of the warnings about PIC not having any effect on that platform.
Signed-off-by: Martin Storsjö <martin@martin.st>
This allows it to be overridden, either by the user on the command
line, or by other sections of the configure script.
Signed-off-by: Martin Storsjö <martin@martin.st>
When targeting the "windows store application" (metro) API subset
(or the windows phone API subset), the getenv function isn't
available. If it is unavailable, just define getenv to NULL.
The check uses check_func_headers, since the function actually
might exist in the libraries, but is hidden in the headers.
The fallback is in config.h since msvc can't do -D defines with
parameters on the command line, and it's used both within the
libraries and the frontend applications (so a libavutil internal
header wouldn't be enough).
Signed-off-by: Martin Storsjö <martin@martin.st>
With the parameter --valgrind-memcheck, the configure script sets
reasonable defaults that can be overridden as explained in the
documentation.
The idea of using set_defaults is from Luca Barbato.
If building libav with -MD in the cflags (for making the MSVC compiler
generate code for using a dynamically linked libc), the system headers
that declare strtod, snprintf and vsnprintf declare the functions as
imported from a DLL. To hook up wrappers of our own for these functions,
the function names are defined to avpriv_*, so that the calling code
within libav calls the wrappers instead. Since these functions
are declared to be imported from DLLs, the calling code expects to
load them from DLL import function pointers (creating references to
_imp__avpriv_strtod instead of directly to avpriv_strtod). If the
libav libraries are not built as DLLs, no such function pointers (as
the calling code expects) are created.
The linker can fix this up automatically in some cases (producing
warnings LNK4217 and LNK4049), if the object files are already
included. By telling the linker to try to include those symbols
(without the _imp prefix as the calling code ends up using),
we get the object files included, so that the linker can do the
automatic fixup. This is done via config.h, so that all (or at least
most) of the object files in our libraries force including the compat
files, to make sure they are included regardless of what files from our
static libraries actually are included.
Signed-off-by: Martin Storsjö <martin@martin.st>
This avoids cases where configure tries to weakly enable an item
which actually is disabled, ending up still enabling dependencies
of the item which itself is only enabled weakly.
More concretely, the h264 decoder suggests error resilience, which
is then enabled weakly (unless manually disabled). Previously,
dsputil, which is a dependency of error resilience, was enabled
even if error resilience wasn't enabled in the end.
Signed-off-by: Martin Storsjö <martin@martin.st>
The variable name 'var' is commonly used to iterate through arguments
in other functions. When the pushvar function internally uses the
variable 'var', it makes pushing/popping the variable 'var' not
work as intended.
Signed-off-by: Martin Storsjö <martin@martin.st>
The gcov/lcov are a common toolchain for visualizing code coverage with
the GNU/Toolchain. The documentation and implementation of this
integration was heavily inspired from the blog entry by Mike Melanson:
http://multimedia.cx/eggs/using-lcov-with-ffmpeg/
The "suncc" atomics implementation uses a suncc specific memory
barrier, but also relies on a few atomic functions from atomic.h,
that are not suncc specific but specific to solaris. This made
the current implementation fail on suncc on linux.
This makes standalone compilation of the eatqi decoder
succeed. The dependency comes from the shared mpeg12dec.o file.
Signed-off-by: Martin Storsjö <martin@martin.st>
Error resilience is enabled by the h264 decoder, unless explicitly
disabled. --disable-everything --enable-decoder=h264 will produce
a h264 decoder with error resilience enabled, while
--disable-everything --enable-decoder=h264 --disable-error-resilience
will produce a h264 decoder with error resilience disabled.
Signed-off-by: Martin Storsjö <martin@martin.st>
This allows dropping the mpegvideo dependency from a number of
components.
This also fixes standalone building of the h264 parser, which
was broken in 64e438697.
Signed-off-by: Martin Storsjö <martin@martin.st>
Not all gcc configurations have an implementation of all the atomic
operations, and some gcc configurations have some atomic builtins
implemented but not all.
Thus check for the most essential function, whose presence should
indicate that all others are present as well, since it can be used
to implement all the other ones.
Signed-off-by: Martin Storsjö <martin@martin.st>
These could be used for reference counting, or for keeping track of
decoding progress in references in multithreaded decoders.
Support is provided by gcc/msvc/suncc intrinsics, with a fallback using
pthread mutexes.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This makes the decoder independent of mpegvideo.
This copy of the draw_horiz_band code is simplified compared to
the "generic" mpegvideo one which still has a number of special
cases for different codecs.
Signed-off-by: Martin Storsjö <martin@martin.st>
On Cygwin systems MinGW headers can be present if the corresponding
packages have been installed. Since the MinGW libc is checked for
first, this results in newlib getting misdetected as MinGW libc.
Previously PIC was enabled as a magic workaround for binaries that
built fine, but failed to function at all. This problem no longer
exists, possibly since the introduction of symbol versioning.
These flags are as linker-specific as other LDFLAGS and thus
need to be translated to the correct linker syntax.
Signed-off-by: Diego Biurrun <diego@biurrun.de>
Also fixes linking in various configs with only individual parts enabled
because the RTP muxer chaining code depends on the general RTP code,
which is now accounted for.
Move some functions from dsputil. The idea is that videodsp contains
functions that are useful for a large and varied set of video decoders.
Currently, it contains emulated_edge_mc() and prefetch().
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
This fixes the automatic use of $foo_extralibs when feature foo
is enabled indirectly through a _select or _suggest.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This allows compiling optimised functions for features not enabled
in the core build and selecting these at runtime if the system has
the necessary support.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This is consistent with usual ARM nomenclature as well as with the
VFPV3 and NEON symbols which both lack the ARM prefix.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This tests instruction set support in both inline and external asm.
If both fail, the base config option is disabled.
Signed-off-by: Mans Rullgard <mans@mansr.com>
The check_insn function tests an instruction in both inline asm and
standalone assembly, and sets _external/_inline config properties
accordingly.
Signed-off-by: Mans Rullgard <mans@mansr.com>
The check_inline_asm function should check the actual C compiler,
not the one used for assembly files. Usually these are the same,
but they might be different, typically when using a compiler other
than gcc.
The check_as should, as its name suggests, test the type of input
the AS command is used with, i.e. a standalond assembly (.S) file.
Finally, check for gnu assembler using the modified check_as as
this reflects actual usage.
Signed-off-by: Mans Rullgard <mans@mansr.com>
These are properties of the targeted core and do not depend on
specific assembly support in the toolchain which if missing will
render the controlling options here disabled.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Probe for the toolchain default architecture version if no --cpu flag
is present or an unknown cpu is specified. Works with gcc, clang and
armcc.
This allows configuring based on the arch version even if it is not
explicitly specified to configure. It also causes an explicit -march
flag to be added to CFLAGS and ASFLAGS, which in turn lets us do
proper instruction set tests with the assembler.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This will allow arch-specific ways of determining the target
variant when none is specified on the command line.
Signed-off-by: Mans Rullgard <mans@mansr.com>
The def files are used for generating import libraries for
other toolchains (in particular, for generating import libraries
for MSVC for DLLs built with mingw).
The def files produced by mingw/gcc contains ordinals for each
exported function. When MSVC tools generate import libraries
from such a def file, MSVC links to the DLL by the ordinals
instead of linking by name.
Since the def files aren't maintained by hand, the ordinal
numbers are assigned (more or less) randomly and any caller
linking to the libs by ordinals will break as soon as the libraries
export more/fewer functions.
Therefore, strip out the ordinals from the generated def files,
to make users link to the libraries by name.
Callers linking to the DLLs using the gcc provided import library
link by name as they should.
Signed-off-by: Martin Storsjö <martin@martin.st>
When targeting the metro API subset, this function still exists in
the link libraries, but is excluded from the headers. This makes
sure w32threads is automatically disabled when targeting this API
subset (since not all the necessary functions for it are available).
Signed-off-by: Martin Storsjö <martin@martin.st>
This simplifies the condition to avoid hardcoding the systems
where the function exists. This also simplifies support for
newer Windows API subsets where this function doesn't exist,
such as Windows Phone 8 and the "metro" API subset of Windows 8.
Signed-off-by: Martin Storsjö <martin@martin.st>
This makes sure minimal configurations such as
"--disable-everything --enable-avconv" will enable the filters
necessary for running avconv, instead of just keeping avconv
disabled (even if the user specified "--enable-avconv").
Signed-off-by: Martin Storsjö <martin@martin.st>
GCC does not appear to have a -march= string for Westmere, which is a
bit surprising as it has a few more instructions than a Nehalem, but
a few less than a Sandy Bridge.
Signed-off-by: Diego Biurrun <diego@biurrun.de>
This is useful for debugging. Dependencies for these files are not
generated due to limitations in many compilers.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This is (erroneously) required to enable various things in the
newlib headers. As cygwin uses newlib, it is covered by this.
Signed-off-by: Mans Rullgard <mans@mansr.com>
A bug in tail call optimisation in gcc 4.3 and later on parisc causes
numerous tests to fail. Disabling this optimisation gives a working
build. See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55023
Signed-off-by: Mans Rullgard <mans@mansr.com>
The -mpowerpc64 and -mpowerpc-gfxopt flags are implicitly set by
-mcpu as needed. Passing them explicitly is redundant and can
conflict with user-supplied flags.
Signed-off-by: Mans Rullgard <mans@mansr.com>
All modern assemblers have this capability. Older NASM versions
that lack the capability produce code that crashes at runtime,
so it's better to error out during the build process instead.
CC: libav-stable@libav.org
Some awk versions do not treat the result of unary + on a (numeric)
string as numeric, giving wrong results when used in a boolean context
Using unary - instead is logically equivalent works as expected.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This isn't too useful as a normal codec, but can be used in
voip style applications. The decoder updates the noise
generator parameters when a packet is given to it for decoding,
but if called with an empty packet, it generates more noise
according to the last parameters.
Signed-off-by: Martin Storsjö <martin@martin.st>
This adds support for building on Plan 9 x86-32. The compat/plan9
directory contains these items:
- replacements for the 'head' and 'printf' shell commands
- wrapper for main() to disable FPU exceptions
Larger required changes to the system are described in the
documentation.
Signed-off-by: Mans Rullgard <mans@mansr.com>
This allows targets to include special objects when linking
executables without including them in (shared) libraries.
Signed-off-by: Mans Rullgard <mans@mansr.com>
The absence of this function will only give a less informative
string back from our fallback implementation of getnameinfo().
Signed-off-by: Mans Rullgard <mans@mansr.com>
This requires the makedef perl script by Derek, from the
c89-to-c99 repo. That scripts produces a .def file, listing
the symbols to be exported, based on the gcc version scripts
and the built object files.
To properly load non-function symbols from DLL files, the
data symbol declarations need to have the attribute
__declspec(dllimport) when building the calling code. (On mingw,
the linker can fix this up automatically, which is why it has not
been an issue so far. If this attribute is omitted, linking
actually succeeds, but reads from the table will not produce the
desired results at runtime.)
MSVC seems to manage to link DLLs (and run properly) even if
this attribute is present while building the library itself
(which normally isn't recommended) - other object files in the
same library manage to link to the symbol (with a small warning
at link time, like "warning LNK4049: locally defined symbol
_avpriv_mpa_bitrate_tab imported" - it doesn't seem to be possible
to squelch this warning), and the definition of the tables
themselves produce a warning that can be squelched ("warning C4273:
'avpriv_mpa_bitrate_tab' : inconsistent dll linkage, see previous
definition of 'avpriv_mpa_bitrate_tab').
In this setup, mingw isn't able to link object files that refer to
data symbols with __declspec(dllimport) without those symbols
actually being linked via a DLL (linking avcodec.dll ends up with
errors like "undefined reference to `__imp__avpriv_mpa_freq_tab'").
The dllimport declspec isn't needed at all in mingw, so we simply
choose not to declare it for other compilers than MSVC that requires
it. (If ICL support later requires it, the condition can be extended
later to include both of them.)
This also implies that code that is built to link to a certain
library as a DLL can't link to the same library as a static library.
Therefore, we only allow building either static or shared but not
both at the same time. (That is, static libraries as such can be,
and actually are, built - this is used for linking the test tools to
internal symbols in the libraries - but e.g. libavformat built to
link to libavcodec as a DLL cannot link statically to libavcodec.)
Also, linking to DLLs is slightly different from linking to shared
libraries on other platforms. DLLs use a thing called import
libraries, which is basically a stub library allowing the linker
to know which symbols exist in the DLL and what name the DLL will
have at runtime.
In mingw/gcc, the import library is usually named libfoo.dll.a,
which goes next to a static library named libfoo.a. This allows
gcc to pick the dynamic one, if available, from the normal -lfoo
switches, just as it does for libfoo.a vs libfoo.so on Unix. On
MSVC however, you need to literally specify the name of the import
library instead of the static library.
Signed-off-by: Martin Storsjö <martin@martin.st>
The name mingw32 as target OS is both misleading, and very little
of the target OS specific settings actually match.
Since the target OS default is set based on uname, the default
(which on MSYS is set to mingw) is overridden by --toolchain=msvc.
Signed-off-by: Martin Storsjö <martin@martin.st>
Add a configure function to pull in a compat object and set up
redirects in one operation. This avoids duplicating conditions
across configure and makefiles.
Signed-off-by: Mans Rullgard <mans@mansr.com>
