diff --git a/litex/build/sim/core/Makefile b/litex/build/sim/core/Makefile
index 7693abb72..9adb97630 100644
--- a/litex/build/sim/core/Makefile
+++ b/litex/build/sim/core/Makefile
@@ -1,7 +1,7 @@
 include variables.mak
 
 CC = gcc
-CFLAGS = -Wall -O3 -ggdb
+CFLAGS = -Wall -O3 -ggdb $(if $(COVERAGE), -DVM_COVERAGE)
 LDFLAGS = -lpthread -ljson-c -lm -lstdc++ -ldl -levent
 
 CC_SRCS ?= "--cc dut.v"
diff --git a/litex/build/sim/core/sim.c b/litex/build/sim/core/sim.c
index 6e62c5cfc..32124ee19 100644
--- a/litex/build/sim/core/sim.c
+++ b/litex/build/sim/core/sim.c
@@ -190,10 +190,12 @@ static void cb(int sock, short which, void *arg)
       if(!s->tickfirst)
 	s->module->tick(s->session);
     }
-  }
 
-  if (litex_sim_got_finish())
-    event_base_loopbreak(base);
+    if (litex_sim_got_finish()) {
+        event_base_loopbreak(base);
+        break;
+    }
+  }
 
   if (!evtimer_pending(ev, NULL)) {
     event_del(ev);
@@ -232,7 +234,6 @@ int main()
     goto out;
   }
 
-
   tv.tv_sec = 0;
   tv.tv_usec = 0;
   ev = event_new(base, -1, EV_PERSIST, cb, vdut);