BB AI running OpenCV 4.6.0 DNN module using OpenCL causes illegal instruction in /usr/lib/


I’ve built the OpenCV 4.6.0 on the BBB AI, previsously flashed the image am57xx-debian-10.3-iot-tidl-armhf-2020-04-06-6gb.img.xz.

The DNN of OpenCV works perfectly using CPU. If the same DNN tester application is instructed to use the OpenCV in the DNN the ILLEGAL ISTRUCTION exception is generated.

The (partial) output rom GDB:

[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/".
[ 8881.956508]~DLT~ 1631~INFO     ~FIFO /tmp/dlt cannot be opened. Retrying later...
[New Thread 0xaf4f1f00 (LWP 1634)]
[New Thread 0xaecf0f00 (LWP 1635)]
[New Thread 0x976e5f00 (LWP 1636)]

Thread 1 "dnntester" received signal SIGILL, Illegal instruction.
0xae3f9d30 in ?? () from /usr/lib/

Pls. help/advice.