diff --git a/src/emu/ovni/event.c b/src/emu/ovni/event.c
index bf97293..f1ee68f 100644
--- a/src/emu/ovni/event.c
+++ b/src/emu/ovni/event.c
@@ -35,10 +35,16 @@ pre_thread_execute(struct emu *emu, struct thread *th)
 	dbg("thread %d runs in %s", th->tid, cpu->name);
 
 	/* First set the CPU in the thread */
-	thread_set_cpu(th, cpu);
+	if (thread_set_cpu(th, cpu) != 0) {
+		err("thread_set_cpu failed");
+		return -1;
+	}
 
 	/* Then set the thread to running state */
-	thread_set_state(th, TH_ST_RUNNING);
+	if (thread_set_state(th, TH_ST_RUNNING) != 0) {
+		err("thread_set_state failed");
+		return -1;
+	}
 
 	/* And then add the thread to the CPU, so tracking channels see the
 	 * updated thread state */
diff --git a/src/emu/system.c b/src/emu/system.c
index 106aac4..039821f 100644
--- a/src/emu/system.c
+++ b/src/emu/system.c
@@ -543,7 +543,10 @@ system_connect(struct system *sys, struct bay *bay, struct recorder *rec)
 			return -1;
 		}
 
-		cpu_add_to_pcf_type(cpu, affinity_type);
+		if (cpu_add_to_pcf_type(cpu, affinity_type) == NULL) {
+			err("cpu_add_to_pcf_type failed for cpu '%s'", cpu->name);
+			return -1;
+		}
 	}
 
 	return 0;