Cannot build on OpenBSD/riscv64

[Brad Smith]

Trying to build on OpenBSD/riscv64 7.6, Clang 16..

openbsd-riscv64$ gmake
GEN libavdevice/libavdevice.version
GEN libavfilter/libavfilter.version
GEN libavformat/libavformat.version
GEN libavcodec/libavcodec.version
GEN libswresample/libswresample.version
GEN libswscale/libswscale.version
GEN libavutil/libavutil.version
CC libavdevice/alldevices.o
In file included from libavdevice/alldevices.c:23:
In file included from ./libavformat/avformat_internal.h:30:
In file included from ./libavformat/avformat.h:312:
In file included from ./libavcodec/codec_par.h:26:
In file included from ./libavutil/avutil.h:301:
In file included from ./libavutil/common.h:49:
In file included from ./libavutil/intmath.h:32:
In file included from ./libavutil/riscv/intmath.h:29:
./libavutil/riscv/cpu.h:78:25: error: call to undeclared function 'ff_get_rv_vlenb'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]

return bits <= (8 * ff_get_rv_vlenb());

1 error generated.

[Rémi Denis-Courmont]

Patch on ML

[Rémi Denis-Courmont]

Note that FFmpeg on RISC-V requires Clang 17 or later. The RISC-V assembler in Clang 16 is a bad joke.

[Brad Smith]

Oh, I understand for Vector support. OpenBSD does not have Vector support yet so I figured it would disable the Vector support and still build without the Vector code. I am hoping within the next few months the system compiler will be updated from 16 to 19.