As pointed out by Andrew (BT #214), using libdav1d as opposed to libaom for decoding (no encoding) is so attractive because it pretty much runs at full speed.  So when FFmpeg 4.2 included the compile option for this, we were highly motivated to put this in as the default for AV1 media loading/editing.  AV1 is yet another codec that seems to be newly relevant.

However as mentioned in a previous email, dav1d inclusion was a big problem for the older system monthly builds.  First, meson had to be at or above version 47 and only 5 out of 18 build systems were.  Consequently, GG ended up eliminating the "meson" requirement and substituting the standard "make" instead.  Then the "nasm" assembler on some of the older systems was not able to compile Dav1d so they had to be switched out for a newer/working version (11 out of 19 were OK).

If we had known the problems that would be encountered in applying libdav1d, I wonder if we would have included it at this time? Also, as mentioned in the BT #214, a remapping for decoding with libdav1d being the preference is in the {cinelerra_path}/ffmpeg/decode.opts file.  To revert to using libaom instead for decoding, you will need to comment out the line:   remap_video_decoder libaom-av1=libdav1d

every time you update Cinelerra.  We have not tested what happens if there is either no libdav1d or libaom so if that creates a different problem, we will have to address that.   gg/Phyllis

The easy workaround, if you do not care about AV1 files, is to add to the configure line in your script:

   ./configure     ....     --disable-dav1d

The better fix, is to upgrade nasm to at least 2.13 or higher.

Here is the list of the problem distro systems: