Why are the simulation waveforms different between Intel® HLS compiler version 19.2 and 20.1 with the explicit_streams_packets_empty example?

Description

When you compile the HLS example  xxx/hls/examples/tutorials/interfaces/explicit_streams_packets_empty with Intel® HLS Compiler version 19.2 and 20.1, you will get different waveforms.  In version 19.2, the signal in_pixels_startofpacket has a start pulse, but in versions 19.3 and 20.1, the start pulse is missing.

19.2

20.1 and 19.3

Resolution

This problem is scheduled to be fixed in Intel® High Level Synthesis version 20.4.