[FFmpeg-user] avformat_find_stream_info broken recently with multiple threads?

[Carl Eugen Hoyos]

Dennis Volodomanov <volodomanov <at> gmail.com> writes:

> 
> Carl,
> 
> Carl Eugen Hoyos wrote:
> > Dennis Volodomanov<volodomanov<at>  gmail.com>  writes:
> >
> >> ./configure --arch=x86 --target-os=mingw32
> >> --cross-prefix=i686-w64-mingw32- --pkg-config=pkg-config
> >> --enable-zlib --enable-bzlib --disable-w32threads --disable-programs
> >> --extra-cflags=-DPTW32_STATIC_LIB --disable-stripping
> >
> > (--enable-zlib, --enable-bzlib and --disable-w32threads
> > look unneeded.)
> Yes, perhaps the two zlibs can go, but they're historically there :)

> The w32threads is needed so that pthreads are used.

Correct, sorry I thought pthreads are now preferred, 
but that is not the case.

> >> ./configure --arch=x86 --target-os=mingw32
> >> --cross-prefix=i686-w64-mingw32- --pkg-config=pkg-config
> >> --enable-zlib --enable-bzlib --disable-w32threads --disable-programs
> >> --extra-cflags=-DPTW32_STATIC_LIB --disable-stripping

> > Does this really produce dll's?
> > (It's been some time since I last built on mingw,
> > so default behaviour may have changed, although I
> > would at least ask if this wouldn't be a bug.)
>
> Yes, it does

That sounds like a serious bug to me, and I suspect 
it is a regression. I will try to find time to 
reproduce this.
Could you confirm again that the following produces 
dll files?
$ make distclean && ./configure-arch=x86 --target-os=mingw32 
--cross-prefix=i686-w64-mingw32- && make

> > Is --extra-cflags=-DPTW32_STATIC_LIB needed?
> > What it is good for? Is there a bug report missing?
> > (Or is there a bug report?)
>
> This is to use the pthreads library I mentioned earlier.

Should this be automatically added when pthreads are used?
Or are you adding this because you prefer static pthreads?

Thank you, Carl Eugen