buffer overflow when a problem has `hold`

[gqqnbig]

$ cat h.sim
begin
hold(1)
end;
$ cim h
Compiling h.sim:
"h.sim", line 3: *** buffer overflow detected ***: terminated
[1]    2072 IOT instruction (core dumped)  cim h

My program only has three lines; one of them is hold(1). When I compile it, cim throws error "buffer overflow detected".

I'm by no means an expert in Simula, but I insist the compiler shouldn't crash out.

I compiled cim on my machine. Its version is cim-5.1-x86_64-pc-linux-gnu.

[SarthakPatkar2006]

Issue: cim crashes with buffer overflow on invalid hold() usage

I noticed that cim crashes with a *** buffer overflow detected *** error when compiling a very small Simula program that calls hold(1) outside of a simulation/process context.

Minimal reproducible example:

begin
hold(1);
end;

Expected behavior:

A clear compile-time error indicating that hold() is only valid inside a Simulation / Process context.

Actual behavior:

The compiler terminates with a buffer overflow error and core dump.

Environment:

cim version: cim-5.1-x86_64-pc-linux-gnu

Platform: Linux x86_64

While the code is semantically invalid, the compiler should ideally report a diagnostic error instead of crashing. This seems like a missing validation check or an unhandled internal state.

I’m reporting this in case it helps improve robustness and error handling. Please let me know if I can assist further or test a fix.