configure: Don't try to enable the log2 function on msvcrt

Some msvcrt versions (the static 64 bit libc in MSVC 10) have
a log2 function, but there is no declaration for it in the headers.
Therefore, the normal configure check might find it, but it can fail
during build or at runtime, depending on whether implicit function
declarations are an error or not.

Therefore simply ignore this function on this platform.

Signed-off-by: Martin Storsjö <martin@martin.st>
configure: Add --disable-inline-asm command line option

This can come in handy for testing and possibly other purposes.
configure: Adjust the xgetbv instrinsic check

The 64 bit cl.exe version 16.00.30319.01 crashes with an internal
compiler error on the current check (and thus deduces it isn't
supported, even if the actual usage in libavuil/x86/cpu.c works
fine), but by assigning the value from the intrinsic to a variable,
or returning it, it works fine.

This error is fixed in cl.exe version 16.00.40219.01.

Signed-off-by: Martin Storsjö <martin@martin.st>
file: Use a normal private context for storing the file descriptor

Previously the file descriptor was stored in the priv_data pointer.

Signed-off-by: Martin Storsjö <martin@martin.st>
flvdec: always set AVFMTCTX_NOHEADER.

New streams may be created at any time, e.g. on codec change.
avplay: fix prototypes for option callbacks.

They have been wrong since 11d957fbd81288e64408e79ed369446346000b29
avplay: get rid of ugly casts in the options table
x86: dsputil: Move specific optimization settings out of global init function

They belong in the init functions specific to each CPU capability.
rtpdec_jpeg: Add support for default quantizers

Generate quantization tables when they are not present in the
first chunk.

Signed-off-by: Martin Storsjö <martin@martin.st>
lavfi/amerge: fix input pad name behaviour.

This fixes two problems:
 - the invalid pad.name stack pointer after init() ends
 - the duplicated name for all inputs
Merge remote-tracking branch 'qatar/master'

* qatar/master:
  rtpdec_jpeg: Add support for default quantizers
  x86: dsputil: Move specific optimization settings out of global init function
  avplay: get rid of ugly casts in the options table
  avplay: fix prototypes for option callbacks.
  flvdec: always set AVFMTCTX_NOHEADER.
  file: Use a normal private context for storing the file descriptor
  configure: Adjust the xgetbv instrinsic check
  configure: Add --disable-inline-asm command line option
  configure: Don't try to enable the log2 function on msvcrt

Conflicts:
	configure
	ffplay.c
	libavcodec/x86/dsputil_mmx.c
	libavformat/file.c
	libavformat/flvdec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
examples/demuxing: add audio decoding/demuxing
ratecontrol: correct predictor in case of stuffing

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
ratecontrol: Dynamically choose a default for rc_max_available_vbv_use

This improves handling of small buffer sizes

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
ratecontrol: fix get_fps() argument

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
ratecontrol: change a commented printf to av_log

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
lavfi/amerge: avoid a forward declaration.
lavfi/amerge: clarify the error message in case of input overlap
lavf/flvenc: convert commented debug log to an av_dlog call

Also add some additional info (DTS and DTS time).
postproc: Fix unprotected inline asm

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>