diff --git a/src/hb-open-type-private.hh b/src/hb-open-type-private.hh
index 36e565f..38d3108 100644
--- a/src/hb-open-type-private.hh
+++ b/src/hb-open-type-private.hh
@@ -84,10 +84,6 @@
 #define Null(Type) (Null<Type>::get())
 
 
-#define ASSERT_SIZE_DATA(Type, size, data) \
-  ASSERT_SIZE (Type, size); \
-  DEFINE_NULL_DATA (Type, size, data)
-
 /* get_for_data() is a static class method returning a reference to an
  * instance of Type located at the input data location.  It's just a
  * fancy, NULL-safe, cast! */
diff --git a/src/hb-ot-layout-common-private.hh b/src/hb-ot-layout-common-private.hh
index 85f228e..d3c5bef 100644
--- a/src/hb-ot-layout-common-private.hh
+++ b/src/hb-ot-layout-common-private.hh
@@ -174,7 +174,8 @@
 				 * = 0xFFFF */
   IndexArray	featureIndex;	/* Array of indices into the FeatureList */
 };
-ASSERT_SIZE_DATA (LangSys, 6, "\0\0\xFF\xFF");
+ASSERT_SIZE (LangSys, 6);
+DEFINE_NULL_DATA (LangSys, 6, "\0\0\xFF\xFF");
 
 
 struct Script
@@ -377,7 +378,8 @@
   USHORT	startCoverageIndex;	/* Coverage Index of first GlyphID in
 					 * range */
 };
-ASSERT_SIZE_DATA (CoverageRangeRecord, 6, "\000\001");
+ASSERT_SIZE (CoverageRangeRecord, 6);
+DEFINE_NULL_DATA (CoverageRangeRecord, 6, "\000\001");
 
 struct CoverageFormat2
 {
@@ -496,7 +498,8 @@
   GlyphID	end;		/* Last GlyphID in the range */
   USHORT	classValue;	/* Applied to all glyphs in the range */
 };
-ASSERT_SIZE_DATA (ClassRangeRecord, 6, "\000\001");
+ASSERT_SIZE (ClassRangeRecord, 6);
+DEFINE_NULL_DATA (ClassRangeRecord, 6, "\000\001");
 
 struct ClassDefFormat2
 {