Encoder hangs with --superres-mode 4

The latest master hangs at ~537 frames when using --superres-mode 4. CPU usage stops and there's no output, even with a debug build. Also happens with --asm c.

I've reproduced this with multiple different input files, so I assume anything long enough will do. Command to reproduce:

ffmpeg -i bbb_sunflower_1080p_60fps_normal.mp4 -an -strict -1 -loglevel quiet -f yuv4mpegpipe - |SvtAv1EncApp -i stdin --keyint 600 --preset 5 --superres-mode 4 --crf 32 -b svttest.ivf

I'm on Linux Mint 20.2. Encoder/compiler version:

Svt[info]: SVT [version]:	SVT-AV1 Encoder Lib v1.4.1-115-gfca45816
Svt[info]: SVT [build]  :	Ubuntu Clang 12.0.0	 64 bit
Svt[info]: LIB Build date: Apr 19 2023 21:55:55