diff --git a/layout/generic/nsFrame.cpp b/layout/generic/nsFrame.cpp
index 658e2f67c807..2110550b8aef 100644
--- a/layout/generic/nsFrame.cpp
+++ b/layout/generic/nsFrame.cpp
@@ -7740,11 +7740,13 @@ nsFrame::DoLayout(nsBoxLayoutState& aState)
                                   nsSize(size.width, NS_UNCONSTRAINEDSIZE),
                                   nsHTMLReflowState::DUMMY_PARENT_REFLOW_STATE);
 
+    AddStateBits(NS_FRAME_IN_REFLOW);
     // Set up a |reflowStatus| to pass into ReflowAbsoluteFrames
     // (just a dummy value; hopefully that's OK)
     nsReflowStatus reflowStatus = NS_FRAME_COMPLETE;
     ReflowAbsoluteFrames(aState.PresContext(), desiredSize,
                          reflowState, reflowStatus);
+    RemoveStateBits(NS_FRAME_IN_REFLOW);
   }
 
   nsSize oldSize(ourRect.Size());
diff --git a/layout/xul/nsBoxFrame.cpp b/layout/xul/nsBoxFrame.cpp
index 9dd88acf5f30..5b0b99fe7d71 100644
--- a/layout/xul/nsBoxFrame.cpp
+++ b/layout/xul/nsBoxFrame.cpp
@@ -928,11 +928,13 @@ nsBoxFrame::DoLayout(nsBoxLayoutState& aState)
     desiredSize.SetTopAscent(ascent);
     desiredSize.mOverflowAreas = GetOverflowAreas();
 
+    AddStateBits(NS_FRAME_IN_REFLOW);
     // Set up a |reflowStatus| to pass into ReflowAbsoluteFrames
     // (just a dummy value; hopefully that's OK)
     nsReflowStatus reflowStatus = NS_FRAME_COMPLETE;
     ReflowAbsoluteFrames(aState.PresContext(), desiredSize,
                          reflowState, reflowStatus);
+    RemoveStateBits(NS_FRAME_IN_REFLOW);
   }
 
   return rv;