diff --git a/layout/tables/nsTableFrame.cpp b/layout/tables/nsTableFrame.cpp
index 3a8a9d5e886b..7a900cf9fa1f 100644
--- a/layout/tables/nsTableFrame.cpp
+++ b/layout/tables/nsTableFrame.cpp
@@ -188,12 +188,7 @@ nsTableFrame::nsTableFrame(nsStyleContext* aContext)
     mCellMap(nsnull),
     mTableLayoutStrategy(nsnull)
 {
-  mBits.mHaveReflowedColGroups  = false;
-  mBits.mCellSpansPctCol        = false;
-  mBits.mNeedToCalcBCBorders    = false;
-  mBits.mIsBorderCollapse       = false;
-  mBits.mResizedColumns         = false; // only really matters if splitting
-  mBits.mGeometryDirty          = false;
+  memset(&mBits, 0, sizeof(mBits));
 }
 
 NS_QUERYFRAME_HEAD(nsTableFrame)