diff --git a/src/common.h b/src/common.h
index 33e960cd44..4aa47d7ab8 100644
--- a/src/common.h
+++ b/src/common.h
@@ -483,7 +483,7 @@ cast(void* p, unsigned offset)
 
 template <class T>
 inline T*
-mask(T* p)
+maskAlignedPointer(T* p)
 {
   return reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(p) & PointerMask);
 }
diff --git a/src/heap.cpp b/src/heap.cpp
index 39e1b3c572..5c87de8b88 100644
--- a/src/heap.cpp
+++ b/src/heap.cpp
@@ -80,7 +80,7 @@ markBitAtomic(uintptr_t* map, unsigned i)
 inline void*
 get(void* o, unsigned offsetInWords)
 {
-  return mask(cast<void*>(o, offsetInWords * BytesPerWord));
+  return maskAlignedPointer(cast<void*>(o, offsetInWords * BytesPerWord));
 }
 
 inline void**
@@ -1179,12 +1179,12 @@ updateHeapMap(Context* c, void* p, void* target, unsigned offset, void* result)
 void*
 update(Context* c, void** p, void* target, unsigned offset, bool* needsVisit)
 {
-  if (mask(*p) == 0) {
+  if (maskAlignedPointer(*p) == 0) {
     *needsVisit = false;
     return 0;
   }
 
-  void* result = update2(c, mask(*p), needsVisit);
+  void* result = update2(c, maskAlignedPointer(*p), needsVisit);
 
   if (result) {
     updateHeapMap(c, p, target, offset, result);
@@ -1297,20 +1297,20 @@ bitsetNext(Context* c, uintptr_t* p)
 void
 collect(Context* c, void** p, void* target, unsigned offset)
 {
-  void* original = mask(*p);
+  void* original = maskAlignedPointer(*p);
   void* parent_ = 0;
   
   if (Debug) {
     fprintf(stderr, "update %p (%s) at %p (%s)\n",
-            mask(*p), segment(c, *p), p, segment(c, p));
+            maskAlignedPointer(*p), segment(c, *p), p, segment(c, p));
   }
 
   bool needsVisit;
-  local::set(p, update(c, mask(p), target, offset, &needsVisit));
+  local::set(p, update(c, maskAlignedPointer(p), target, offset, &needsVisit));
 
   if (Debug) {
     fprintf(stderr, "  result: %p (%s) (visit? %d)\n",
-            mask(*p), segment(c, *p), needsVisit);
+            maskAlignedPointer(*p), segment(c, *p), needsVisit);
   }
 
   if (not needsVisit) return;
@@ -1966,10 +1966,10 @@ class MyHeap: public Heap {
         bool dirty = false;
         for (unsigned i = 0; i < count; ++i) {
           void** target = static_cast<void**>(p) + offset + i;
-          if (targetNeedsMark(mask(*target))) {
+          if (targetNeedsMark(maskAlignedPointer(*target))) {
             if (DebugFixies) {
               fprintf(stderr, "dirty fixie %p at %d (%p): %p\n",
-                      f, offset, f->body() + offset, mask(*target));
+                      f, offset, f->body() + offset, maskAlignedPointer(*target));
             }
 
             dirty = true;
@@ -1994,7 +1994,7 @@ class MyHeap: public Heap {
 
         for (unsigned i = 0; i < count; ++i) {
           void** target = static_cast<void**>(p) + offset + i;
-          if (targetNeedsMark(mask(*target))) {
+          if (targetNeedsMark(maskAlignedPointer(*target))) {
 #ifdef USE_ATOMIC_OPERATIONS
             map->markAtomic(target);
 #else
@@ -2041,7 +2041,7 @@ class MyHeap: public Heap {
   }
 
   virtual Status status(void* p) {
-    p = mask(p);
+    p = maskAlignedPointer(p);
 
     if (p == 0) {
       return Null;
diff --git a/src/machine.cpp b/src/machine.cpp
index 6660ae891e..eda7f87259 100644
--- a/src/machine.cpp
+++ b/src/machine.cpp
@@ -2763,7 +2763,7 @@ class HeapClient: public Heap::Client {
   virtual unsigned sizeInWords(void* p) {
     Thread* t = m->rootThread;
 
-    object o = static_cast<object>(m->heap->follow(mask(p)));
+    object o = static_cast<object>(m->heap->follow(maskAlignedPointer(p)));
 
     unsigned n = baseSize(t, o, static_cast<object>
                           (m->heap->follow(objectClass(t, o))));
@@ -2778,7 +2778,7 @@ class HeapClient: public Heap::Client {
   virtual unsigned copiedSizeInWords(void* p) {
     Thread* t = m->rootThread;
 
-    object o = static_cast<object>(m->heap->follow(mask(p)));
+    object o = static_cast<object>(m->heap->follow(maskAlignedPointer(p)));
     assert(t, not objectFixed(t, o));
 
     unsigned n = baseSize(t, o, static_cast<object>
@@ -2794,7 +2794,7 @@ class HeapClient: public Heap::Client {
   virtual void copy(void* srcp, void* dstp) {
     Thread* t = m->rootThread;
 
-    object src = static_cast<object>(m->heap->follow(mask(srcp)));
+    object src = static_cast<object>(m->heap->follow(maskAlignedPointer(srcp)));
     assert(t, not objectFixed(t, src));
 
     object class_ = static_cast<object>
@@ -2815,7 +2815,7 @@ class HeapClient: public Heap::Client {
   }
 
   virtual void walk(void* p, Heap::Walker* w) {
-    object o = static_cast<object>(m->heap->follow(mask(p)));
+    object o = static_cast<object>(m->heap->follow(maskAlignedPointer(p)));
     ::walk(m->rootThread, w, o, 0);
   }
 
diff --git a/src/machine.h b/src/machine.h
index c315661ddb..e972a3be9d 100644
--- a/src/machine.h
+++ b/src/machine.h
@@ -1611,7 +1611,7 @@ typedef uint64_t (JNICALL *FastNativeFunction)(Thread*, object, uintptr_t*);
 inline object
 objectClass(Thread*, object o)
 {
-  return mask(cast<object>(o, 0));
+  return maskAlignedPointer(cast<object>(o, 0));
 }
 
 inline unsigned