V9017

Code

V9017

Message

Container declares a maximum call depth of zero which is invalid

The container’s declared worst-case call depth (FileHeader.max_call_depth) is zero. VmReady::start rejects the container before any init code runs, so no PLC instructions execute.

Every program needs at least one call frame for its entry function, so codegen always computes a depth of one or more (the longest path through CALL and user-FB_CALL edges, counting the entry frame). A declared depth of zero therefore means the field was never populated — a legacy or hand-built container.

To resolve:

• Recompile the program so codegen writes a valid max_call_depth.

• If you build containers by hand, set max_call_depth to the program’s true worst-case call depth (at least 1).

Think IronPLC is wrong about this?

If you believe this diagnostic is incorrect, open an issue on GitHub with a small sample that demonstrates the problem.