Segmentation Fault in hwdec_devices_get_first (devs=0x0) at ../video/hwdec.c:45

[lvml]

mpv version and platform

current git master

Reproduction steps

On a system that has no "hwdec" acceleration:

mpv --vf=lavfi=graph="scale=w=1920:h=1080" some_file.mp4

Expected behavior

does not crash

Actual behavior

crashes due to zero-pointer de-referentation:

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff79b5bd0 in pthread_mutex_lock () from /lib64/libpthread.so.0
(gdb) bt
#0  0x00007ffff79b5bd0 in pthread_mutex_lock () from /lib64/libpthread.so.0
#1  0x00000000004a224e in hwdec_devices_get_first (devs=0x0) at ../video/hwdec.c:45
#2  0x00000000004b0196 in recreate_graph (vf=vf@entry=0x8cbb50, fmt=fmt@entry=0x8cbba4) at ../video/filter/vf_lavfi.c:177
#3  0x00000000004b0317 in reconfig (vf=0x8cbb50, in=0x8cbba4, out=0x8cbbe4) at ../video/filter/vf_lavfi.c:224
#4  0x00000000004acdd7 in vf_reconfig_wrapper (p=0x7fffffffd7b0, vf=0x8cbb50) at ../video/filter/vf.c:617
#5  vf_reconfig (c=0x7f23f0, params=params@entry=0x7fffffffdae0) at ../video/filter/vf.c:655
#6  0x000000000047e8cd in filter_reconfig (mpctx=mpctx@entry=0x78f320, vo_c=0x7f5c00) at ../player/video.c:212
#7  0x000000000047eaa6 in video_filter (mpctx=mpctx@entry=0x78f320, eof=eof@entry=false) at ../player/video.c:642
#8  0x000000000047ebf7 in video_decode_and_filter (mpctx=mpctx@entry=0x78f320) at ../player/video.c:711
#9  0x00000000004803c8 in video_output_image (mpctx=0x78f320) at ../player/video.c:863
#10 write_video (mpctx=mpctx@entry=0x78f320) at ../player/video.c:1369
#11 0x000000000047b9ea in run_playloop (mpctx=mpctx@entry=0x78f320) at ../player/playloop.c:1089
#12 0x0000000000472c11 in play_current_file (mpctx=0x78f320) at ../player/loadfile.c:1262

(As a local work-around for me I added

struct mp_hwdec_ctx *hwdec_devices_get_first(struct mp_hwdec_devices *devs)
{
    if (devs == NULL) return NULL;

)