diff --git a/src/include/postgres.h b/src/include/postgres.h
index ff2c5c0..387d9f4 100644
--- a/src/include/postgres.h
+++ b/src/include/postgres.h
@@ -790,6 +790,35 @@ extern Datum Float8GetDatum(float8 X);
 #define Float4GetDatumFast(X) PointerGetDatum(&(X))
 #endif
 
+typedef struct dsa_area dsa_area;
+
+/*
+ * If this system only uses a 32-bit value for Size, then use the 32-bit
+ * implementation of DSA.  This limits the amount of DSA that can be created
+ * to something significantly less than the entire 4GB address space because
+ * the DSA pointer must encode both a segment identifier and an offset, but
+ * that shouldn't be a significant limitation in practice.
+ *
+ * If this system doesn't support atomic operations on 64-bit values, then
+ * we fall back to 32-bit dsa_pointer for lack of other options.
+ *
+ * For testing purposes, USE_SMALL_DSA_POINTER can be defined to force the use
+ * of 32-bit dsa_pointer even on systems capable of supporting a 64-bit
+ * dsa_pointer.
+ */
+#if SIZEOF_SIZE_T == 4 || !defined(PG_HAVE_ATOMIC_U64_SUPPORT) || \
+	defined(USE_SMALL_DSA_POINTER)
+#define SIZEOF_DSA_POINTER 4
+#else
+#define SIZEOF_DSA_POINTER 8
+#endif
+
+#if SIZEOF_DSA_POINTER == 4
+typedef uint32 dsa_pointer;
+#else
+typedef uint64 dsa_pointer;
+#endif
+
 
 /* ----------------------------------------------------------------
  *				Section 3:	exception handling backend support
diff --git a/src/include/utils/dsa.h b/src/include/utils/dsa.h
index bb634e7..d9b4366 100644
--- a/src/include/utils/dsa.h
+++ b/src/include/utils/dsa.h
@@ -21,28 +21,7 @@
 
 /* The opaque type used for an area. */
 struct dsa_area;
-typedef struct dsa_area dsa_area;
 
-/*
- * If this system only uses a 32-bit value for Size, then use the 32-bit
- * implementation of DSA.  This limits the amount of DSA that can be created
- * to something significantly less than the entire 4GB address space because
- * the DSA pointer must encode both a segment identifier and an offset, but
- * that shouldn't be a significant limitation in practice.
- *
- * If this system doesn't support atomic operations on 64-bit values, then
- * we fall back to 32-bit dsa_pointer for lack of other options.
- *
- * For testing purposes, USE_SMALL_DSA_POINTER can be defined to force the use
- * of 32-bit dsa_pointer even on systems capable of supporting a 64-bit
- * dsa_pointer.
- */
-#if SIZEOF_SIZE_T == 4 || !defined(PG_HAVE_ATOMIC_U64_SUPPORT) || \
-	defined(USE_SMALL_DSA_POINTER)
-#define SIZEOF_DSA_POINTER 4
-#else
-#define SIZEOF_DSA_POINTER 8
-#endif
 
 /*
  * The type of 'relative pointers' to memory allocated by a dynamic shared
@@ -52,7 +31,6 @@ typedef struct dsa_area dsa_area;
  * operations.
  */
 #if SIZEOF_DSA_POINTER == 4
-typedef uint32 dsa_pointer;
 typedef pg_atomic_uint32 dsa_pointer_atomic;
 #define dsa_pointer_atomic_init pg_atomic_init_u32
 #define dsa_pointer_atomic_read pg_atomic_read_u32
@@ -61,7 +39,6 @@ typedef pg_atomic_uint32 dsa_pointer_atomic;
 #define dsa_pointer_atomic_compare_exchange pg_atomic_compare_exchange_u32
 #define DSA_POINTER_FORMAT "%08x"
 #else
-typedef uint64 dsa_pointer;
 typedef pg_atomic_uint64 dsa_pointer_atomic;
 #define dsa_pointer_atomic_init pg_atomic_init_u64
 #define dsa_pointer_atomic_read pg_atomic_read_u64