Forum Discussion
New ContributorQuartus Pro 25.3 crash using rhel7/8
Hello everybody
I'm working on an Agilex-5 project since fex months on our internal couputer farm using Quartus Pro 25.3. To generate the final bitstream, a bash script is used to execute all the steps. Until now, we have no specific issue using this script with Quartus.
But since few days, we're unable to generate the project because Quartus Pro returns strange errors (see attachments). We also tried to use latest 23.5.1 version on an Ubuntu host under WSL and we also saw the same errors.
Running Quartus GUI may also end with same error. (see quartus_4.png)
Has anyone already experienced this issue?
Thanks a lot
Benjamin
Hi all,
The KDB link had been live check https://community.altera.com/kb/knowledge-base/why-do-i-unexpectedly-observe-intermittent-ddm-errors/349714
22 Replies
MoXWe experience the same error since January 10, 2026:
Error (22912): Unhandled exception:
Fatal Error: Assertion failed tools/cpp/ddm/ddm_assessor.cpp:53: DDM_T::verify_token(token) : Cannot identify the client
from function assertion_error in tools/cpp/ddm_report/ddm_report_msg.cpp@455- Milan_S
We are seeing a very similar issue on Windows with Quartus Prime Pro 25.1.1 Build 125 + Patch 1.03.
Compilation (Analysis & Synthesis) freezes reproducibly depending on the system time:
Before ~11 AM: compilation always completes normally.
After ~11 AM: the first compilation attempt of the day hangs indefinitely.
This happens even:
– immediately after reboot,
– on weekends,
– with all db/, qdb/, and temp folders deleted,
– using both GUI and quartus_sh --flow compile,
– with Platform Designer closed or open.
We confirmed that if we manually set the system clock back to the morning (e.g., 08:00), the same project compiles successfully again.
If we restore the real time → the freeze returns.
This looks very similar to the recent reports of unexpected freezes in various Quartus 24.x–25.x versions starting around mid‑January 2026.
