fix incidental finding that return codes weren't being checked properly on witness conversion subprocesses

sbysrc/sby_engine_aiger.py

@@ -192,6 +192,7 @@ def aigsmt_trace_callback(task, engine_idx, proc_status, *, run_aigsmt, smtbmc_v
         task, f"engine_{engine_idx}", [],
         f"cd {task.workdir}; {task.exe_paths['witness']} aiw2yw engine_{engine_idx}/{name}.aiw model/design_aiger.ywa engine_{engine_idx}/{name}{aiw2yw_suffix}.yw",
     )
+    witness_proc.checkretcode = True
     final_proc = witness_proc
 
     if run_aigsmt:

sbysrc/sby_engine_btor.py

@@ -223,6 +223,7 @@ def run(mode, task, engine_idx, engine):
                     task, f"engine_{engine_idx}.trace{suffix}", [],
                     f"cd {task.workdir}; {task.exe_paths['witness']} wit2yw engine_{engine_idx}/trace{suffix}.wit model/{model}.ywb engine_{engine_idx}/trace{suffix}.yw",
                 )
+                yw_proc.checkretcode = True
                 common_state.running_procs += 1
                 yw_proc.register_exit_callback(simple_exit_callback)
 

sbysrc/sby_sim.py

@@ -99,6 +99,7 @@ def sim_witness_trace(prefix, task, engine_idx, witness_file, *, append, inducti
         deps,
         f"""cd {task.workdir}/engine_{engine_idx}; {task.exe_paths["yosys"]} -ql {trace_name}.log {trace_name}.ys""",
     )
+    proc.checkretcode = True
     proc.noprintregex = re.compile(r"Warning: Assert .* failed.*")
     proc.register_exit_callback(exit_callback)
     return proc