media split broke ncdirect

[dankamongmen]

Somewhere in the course of #339, it appears that we broke ncdirect's capability to play media. ncls is broken; ncneofetch shows no image, zorn, alas.

[dankamongmen]

The relevant PR is #1297.

[dankamongmen]

I think what's going on here is that we're fouling up the linking. there's no libav in ncls or ncneofetch, which aren't showing images, but there is libav in notcurses-demo and ncplayer, which are:

[schwarzgerat](0) $ ldd ncneofetch | grep libav
[schwarzgerat](1) $ ldd ncls | grep libav
[schwarzgerat](1) $ ldd ncplayer | grep libav
	libavcodec.so.58 => /usr/lib/x86_64-linux-gnu/libavcodec.so.58 (0x00007f2f8c204000)
	libavformat.so.58 => /usr/lib/x86_64-linux-gnu/libavformat.so.58 (0x00007f2f8bf86000)
	libavutil.so.56 => /usr/lib/x86_64-linux-gnu/libavutil.so.56 (0x00007f2f8bc2c000)
[schwarzgerat](0) $ ldd notcurses-demo | grep libav
	libavcodec.so.58 => /usr/lib/x86_64-linux-gnu/libavcodec.so.58 (0x00007f231c21c000)
	libavformat.so.58 => /usr/lib/x86_64-linux-gnu/libavformat.so.58 (0x00007f231bf9e000)
	libavutil.so.56 => /usr/lib/x86_64-linux-gnu/libavutil.so.56 (0x00007f231bc44000)
[schwarzgerat](0) $ 

[dankamongmen]

It looks like this comes down to libnotcurses++.so not having libnotcurses.so in its linkage (nor av):

[schwarzgerat](0) $ ldd libnotcurses++.so
	linux-vdso.so.1 (0x00007ffe88540000)
	libnotcurses-core.so.2 => /home/dank/src/dankamongmen/notcurses/build/libnotcurses-core.so.2 (0x00007f9f66c78000)
	libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f9f66a63000)
	libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f9f66a49000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f9f66884000)
	libtinfo.so.6 => /lib/x86_64-linux-gnu/libtinfo.so.6 (0x00007f9f66855000)
	libreadline.so.8 => /lib/x86_64-linux-gnu/libreadline.so.8 (0x00007f9f667fc000)
	libunistring.so.2 => /usr/lib/x86_64-linux-gnu/libunistring.so.2 (0x00007f9f6667a000)
	libqrcodegen.so.1 => /usr/lib/x86_64-linux-gnu/libqrcodegen.so.1 (0x00007f9f66672000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f9f66650000)
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f9f6650c000)
	/lib64/ld-linux-x86-64.so.2 (0x00007f9f66cc2000)
[schwarzgerat](0) $ 

ncls uses libnotcurses++. ncneofetch does not, though, and likewise shows neither libnotcurses nor libav:

[schwarzgerat](0) $ ldd ncneofetch 
	linux-vdso.so.1 (0x00007fff9c343000)
	libnotcurses-core.so.2 => /home/dank/src/dankamongmen/notcurses/build/libnotcurses-core.so.2 (0x00007f863db3b000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f863dad1000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f863d90c000)
	libtinfo.so.6 => /lib/x86_64-linux-gnu/libtinfo.so.6 (0x00007f863d8dd000)
	libreadline.so.8 => /lib/x86_64-linux-gnu/libreadline.so.8 (0x00007f863d886000)
	libunistring.so.2 => /usr/lib/x86_64-linux-gnu/libunistring.so.2 (0x00007f863d704000)
	libqrcodegen.so.1 => /usr/lib/x86_64-linux-gnu/libqrcodegen.so.1 (0x00007f863d6fa000)
	libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f863d52d000)
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f863d3e9000)
	/lib64/ld-linux-x86-64.so.2 (0x00007f863dba7000)
	libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f863d3cf000)
[schwarzgerat](0) $ 

[dankamongmen]

This despite:

/usr/bin/cc -O2 -g -DNDEBUG CMakeFiles/ncneofetch.dir/src/fetch/main.c.o CMakeFiles/ncneofetch.dir/src/fetch/ncart.c.o -o ncneofetch  -Wl,-rpath,/home/dank/src/dankamongmen/notcurses/build: libnotcurses.so libnotcurses-core.so.2.1.5 -lpthread -lavcodec -lavformat -lswscale -lavutil 

[dankamongmen]

The point of failure in both is of course ncvisual_from_file().

[dankamongmen]

working ncplayer is linked thusly:

/usr/bin/cmake -E cmake_link_script CMakeFiles/ncplayer.dir/link.txt --verbose=1
/usr/bin/c++ -O2 -g -DNDEBUG CMakeFiles/ncplayer.dir/src/view/view.cpp.o CMakeFiles/ncplayer.dir/src/compat/compat.c.o -o ncplayer  -Wl,-rpath,/home/dank/src/dankamongmen/notcurses/build: libnotcurses++.so.2.1.5 libnotcurses.so libnotcurses-core.so.2.1.5 -lpthread -lavcodec -lavformat -lswscale -lavutil 

non-working ncls is linked:

/usr/bin/cmake -E cmake_link_script CMakeFiles/ncls.dir/link.txt --verbose=1
/usr/bin/c++ -O2 -g -DNDEBUG CMakeFiles/ncls.dir/src/ls/main.cpp.o -o ncls  -Wl,-rpath,/home/dank/src/dankamongmen/notcurses/build: libnotcurses++.so.2.1.5 libnotcurses.so libnotcurses-core.so.2.1.5 -lpthread -lavcodec -lavformat -lswscale -lavutil 

everything's the same except ncplayer includes compat.o. Argh!

[dankamongmen]

Nope, adding compat.o doesn't change anything (as expected).....

[dankamongmen]

-Wl,-no-as-needed fixes this up. can we embed that into pkg-config?

[dankamongmen]

Setting CMAKE_LINK_WHAT_YOU_USE to ON has resolved this problem, but I don't consider this a great fix by any means. I don't think it will propagate to other users of Notcurses, and it results in our binaries linking unnecessary materials. Maybe #1301 will give us a better solution?

[dankamongmen]

I'm thinking that ncls and ncneofetch both use only ncdirect_render_image(), and they're the two that don't get libnotcurses.so linked in. Even humble notcurses-input gets it. Strange.