diff --git a/runtime/gc.c b/runtime/gc.c
index b8d5d0540..5f5c937b7 100644
--- a/runtime/gc.c
+++ b/runtime/gc.c
@@ -277,9 +277,10 @@ void compact_phase (size_t additional_size) {
   size_t next_heap_pseudo_size = MAX(next_heap_size, heap.size);
 
   memory_chunk old_heap = heap;
-  heap.begin            = mremap(heap.begin, WORDS_TO_BYTES(heap.size), WORDS_TO_BYTES(next_heap_pseudo_size), MREMAP_MAYMOVE);
+  heap.begin            = mmap(NULL, WORDS_TO_BYTES(next_heap_pseudo_size), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  memcpy(heap.begin, old_heap.begin, WORDS_TO_BYTES(old_heap.size));
   if (heap.begin == MAP_FAILED) {
-    perror("ERROR: compact_phase: mremap failed\n");
+    perror("ERROR: compact_phase: mmap failed\n");
     exit(1);
   }
   heap.end     = heap.begin + next_heap_pseudo_size;
@@ -290,6 +291,10 @@ void compact_phase (size_t additional_size) {
   physically_relocate(&old_heap);
 
   heap.current = heap.begin + live_size;
+//  if (munmap(old_heap.begin, old_heap.size) < 0) {
+//      perror("ERROR: compact_phase: munmap failed\n");
+//      exit(1);
+//  }
 }
 
 size_t compute_locations () {