diff --git a/build_windows/db.h b/build_windows/db.h
index 31d7775..00ec457 100644
--- a/build_windows/db.h
+++ b/build_windows/db.h
@@ -133,7 +133,7 @@ typedef u_int32_t uintptr_t;
 typedef int64_t off_t;
 typedef int32_t pid_t;
 #ifdef HAVE_MIXED_SIZE_ADDRESSING
-typedef u_int32_t db_size_t;
+typedef u_int64_t db_size_t;
 #else
 typedef size_t db_size_t;
 #endif
@@ -143,7 +143,7 @@ typedef int64_t ssize_t;
 typedef int32_t ssize_t;
 #endif
 #ifdef HAVE_MIXED_SIZE_ADDRESSING
-typedef int32_t db_ssize_t;
+typedef int64_t db_ssize_t;
 #else
 typedef ssize_t db_ssize_t;
 #endif
diff --git a/build_windows/db_int.h b/build_windows/db_int.h
index b1453d5..d78e52e 100644
--- a/build_windows/db_int.h
+++ b/build_windows/db_int.h
@@ -196,9 +196,11 @@ typedef SH_TAILQ_HEAD(__hash_head) DB_HASHTAB;
  * HAVE_MIXED_SIZE_ADDRESSING is defined.
  */
 #ifdef HAVE_MIXED_SIZE_ADDRESSING
-#define DB_ALIGN8 __declspec(align(8))
+#define DB_ALIGN8_BEFORE __declspec(align(8))
+#define DB_ALIGN8_AFTER
 #else
-#define DB_ALIGN8
+#define DB_ALIGN8_BEFORE
+#define DB_ALIGN8_AFTER
 #endif
 
 /*
diff --git a/src/dbinc/db.in b/src/dbinc/db.in
index 92ac822..7722ed1 100644
--- a/src/dbinc/db.in
+++ b/src/dbinc/db.in
@@ -105,13 +105,13 @@ extern "C" {
 @pid_t_decl@
 @size_t_decl@
 #ifdef HAVE_MIXED_SIZE_ADDRESSING
-typedef u_int32_t db_size_t;
+typedef u_int64_t db_size_t;
 #else
 typedef size_t db_size_t;
 #endif
 @ssize_t_decl@
 #ifdef HAVE_MIXED_SIZE_ADDRESSING
-typedef int32_t db_ssize_t;
+typedef int64_t db_ssize_t;
 #else
 typedef ssize_t db_ssize_t;
 #endif
diff --git a/src/dbinc/db_int.in b/src/dbinc/db_int.in
index eae85c9..e3da14c 100644
--- a/src/dbinc/db_int.in
+++ b/src/dbinc/db_int.in
@@ -195,9 +195,11 @@ typedef SH_TAILQ_HEAD(__hash_head) DB_HASHTAB;
  * HAVE_MIXED_SIZE_ADDRESSING is defined.
  */
 #ifdef HAVE_MIXED_SIZE_ADDRESSING
-#define DB_ALIGN8 @DB_STRUCT_ALIGN8@
+#define DB_ALIGN8_BEFORE
+#define DB_ALIGN8_AFTER @DB_STRUCT_ALIGN8@
 #else
-#define DB_ALIGN8
+#define DB_ALIGN8_BEFORE
+#define DB_ALIGN8_AFTER
 #endif
 
 /*
diff --git a/src/dbinc/mp.h b/src/dbinc/mp.h
index e00055f..c4a9e87 100644
--- a/src/dbinc/mp.h
+++ b/src/dbinc/mp.h
@@ -573,7 +573,7 @@ struct __bh { /* SHARED */
 	 * (We guarantee size_t alignment to applications in the documentation,
 	 * too.)
 	 */
-	DB_ALIGN8	u_int8_t buf[1];	/* Variable length data. */
+	DB_ALIGN8_BEFORE u_int8_t buf[1] DB_ALIGN8_AFTER; /* Variable length data. */
 };
 
 /*
diff --git a/src/dbinc/txn.h b/src/dbinc/txn.h
index 9b04727..7943f5f 100644
--- a/src/dbinc/txn.h
+++ b/src/dbinc/txn.h
@@ -47,7 +47,7 @@ struct __txn_logrec;	typedef struct __txn_logrec DB_TXNLOGREC;
  * except for any pointer fields that are filled in only when the struct is
  * being populated for output through the API.
  */
-DB_ALIGN8 struct __db_txn_stat_int { /* SHARED */
+DB_ALIGN8_BEFORE struct __db_txn_stat_int { /* SHARED */
 	u_int32_t st_nrestores;		/* number of restored transactions
 					   after recovery. */
 #ifndef __TEST_DB_NO_STATISTICS
@@ -67,7 +67,7 @@ DB_ALIGN8 struct __db_txn_stat_int { /* SHARED */
 	uintmax_t st_region_nowait;	/* Region lock granted without wait. */
 	roff_t	  st_regsize;		/* Region size. */
 #endif
-};
+} DB_ALIGN8_AFTER;
 
 /*
  * Internal data maintained in shared memory for each transaction.