diff --git a/src/bootimage.cpp b/src/bootimage.cpp
index dd42ccd555..7a9d82e7a3 100644
--- a/src/bootimage.cpp
+++ b/src/bootimage.cpp
@@ -64,12 +64,12 @@ makeCodeImage(Thread* t, Zone* zone, BootImage* image, uint8_t* code,
           object method = arrayBody(t, classMethodTable(t, c), i);
           if ((methodCode(t, method) or (methodFlags(t, method) & ACC_NATIVE))
               and ((methodName == 0
-                    or strcmp
+                    or ::strcmp
                     (reinterpret_cast<char*>
                      (&byteArrayBody
                       (t, vm::methodName(t, method), 0)), methodName) == 0)
                    and (methodSpec == 0
-                        or strcmp
+                        or ::strcmp
                         (reinterpret_cast<char*>
                          (&byteArrayBody
                           (t, vm::methodSpec(t, method), 0)), methodSpec)
diff --git a/src/heapwalk.cpp b/src/heapwalk.cpp
index 828f51194e..a34baf96dc 100644
--- a/src/heapwalk.cpp
+++ b/src/heapwalk.cpp
@@ -15,6 +15,8 @@ using namespace vm;
 
 namespace {
 
+namespace local {
+
 const uintptr_t PointerShift = log(BytesPerWord);
 
 class Context;
@@ -157,7 +159,7 @@ find(Context* c, object p)
 int
 Set::find(object value)
 {
-  Set::Entry* e = ::find(context, value);
+  Set::Entry* e = local::find(context, value);
   if (e) {
     return e->number;
   } else {
@@ -328,6 +330,8 @@ class MyHeapWalker: public HeapWalker {
   HeapVisitor* visitor;
 };
 
+} // namespace local
+
 } // namespace
 
 namespace vm {
@@ -335,7 +339,8 @@ namespace vm {
 HeapWalker*
 makeHeapWalker(Thread* t, HeapVisitor* v)
 {
-  return new (t->m->heap->allocate(sizeof(MyHeapWalker))) MyHeapWalker(t, v);
+  return new (t->m->heap->allocate(sizeof(local::MyHeapWalker)))
+    local::MyHeapWalker(t, v);
 }
 
 } // namespace vm