diff --git a/common/rfb/Decoder.cxx b/common/rfb/Decoder.cxx
index df785eb..370e1f9 100644
--- a/common/rfb/Decoder.cxx
+++ b/common/rfb/Decoder.cxx
@@ -44,6 +44,14 @@
   region->reset(rect);
 }
 
+bool Decoder::doRectsConflict(const Rect& rectA, const void* bufferA,
+                              size_t buflenA, const Rect& rectB,
+                              const void* bufferB, size_t buflenB,
+                              const ConnParams& cp)
+{
+  return false;
+}
+
 bool Decoder::supported(int encoding)
 {
   switch (encoding) {