[FFmpeg-trac] #10809(build system:closed): libvulkan.so not linked when `--enable-vulkan`.

[FFmpeg]

#10809: libvulkan.so not linked when `--enable-vulkan`.
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             Reporter:  Atemu   |                    Owner:  (none)
                 Type:  defect  |                   Status:  closed
             Priority:  normal  |                Component:  build system
              Version:  6.1     |               Resolution:  invalid
             Keywords:          |               Blocked By:
             Blocking:          |  Reproduced by developer:  0
Analyzed by developer:  0       |
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Comment (by Atemu):

 Hi, that is indeed the issue; it is not found via dlopen. That is not the
 root cause however.

 We ensure all libs required by the executable can be found via dlopen by
 explicitly setting the rpath to input-addressed paths of all libraries
 required by the executable.

 Above version 5 however, the ffmpeg executable do not declare themselves
 to require libvulkan.so unless `--enable-libplacebo` is set (see output of
 `ldd` in the OP).

 My understanding is that, because libvulkan.so is not required, the
 Nixpkgs stdenv does not inject the library into the executable's rpath. I
 don't know how that would work out on regular FHS distros because it's
 been years since I used one but I can't imagine it'd work.

 The root cause here appears to be ffmpeg's build scripts producing an ELF
 that is missing the libvulkan.so dependency.

 Are you able to reproduce the `ldd` output of `--enable-vulkan --disable-
 libplacebo` vs. `--enable-vulkan --enable-libplacebo` that I observed on
 your distro aswell?
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10809#comment:2>
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