diff --git a/src/interpret.cpp b/src/interpret.cpp
index 9f28a2f769..c3617122a5 100644
--- a/src/interpret.cpp
+++ b/src/interpret.cpp
@@ -3166,7 +3166,7 @@ class MyProcessor: public Processor {
   }
 
   virtual void dispose(vm::Thread* t) {
-    t->m->heap->free(t, sizeof(Thread));
+    t->m->heap->free(t, sizeof(Thread) + t->m->stackSizeInBytes);
   }
 
   virtual void dispose() {
diff --git a/src/posix.cpp b/src/posix.cpp
index 6b2184011b..6ea15ab118 100644
--- a/src/posix.cpp
+++ b/src/posix.cpp
@@ -904,6 +904,7 @@ class MySystem: public System {
   }
 
   virtual void abort() {
+    *static_cast<void**>(0) = 0;
     ::abort();
   }