erts: Make DFLAG_BIG_CREATION mandatory

2 files changed, 17 insertions, 18 deletions

diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index c4bb967592..38ac972f51 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -54,11 +54,12 @@
 #define DFLAG_DIST_MANDATORY (DFLAG_EXTENDED_REFERENCES         \
                               | DFLAG_EXTENDED_PIDS_PORTS       \
 			      | DFLAG_UTF8_ATOMS                \
-			      | DFLAG_NEW_FUN_TAGS)
+			      | DFLAG_NEW_FUN_TAGS              \
+                              | DFLAG_BIG_CREATION)
 
 /*
  * Additional optimistic flags when encoding toward pending connection.
- * If remote node (erl_interface) does not supporting these then we may need
+ * If remote node (erl_interface) does not support these then we may need
  * to transcode messages enqueued before connection setup was finished.
  */
 #define DFLAG_DIST_HOPEFULLY (DFLAG_EXPORT_PTR_TAG              \
@@ -75,7 +76,6 @@
                             | DFLAG_SMALL_ATOM_TAGS           \
                             | DFLAG_UTF8_ATOMS                \
                             | DFLAG_MAP_TAG                   \
-                            | DFLAG_BIG_CREATION              \
                             | DFLAG_SEND_SENDER               \
                             | DFLAG_BIG_SEQTRACE_LABELS       \
                             | DFLAG_EXIT_PAYLOAD              \
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index 73eae614fa..bcaf8eb26c 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -51,18 +51,17 @@
 
 #define MAX_STRING_LEN 0xffff
 
-/* MAX value for the creation field in pid, port and reference
-   for the local node and for the current external format.
-
-   Larger creation values than this are allowed in external pid, port and refs
-   encoded with NEW_PID_EXT, NEW_PORT_EXT and NEWER_REFERENCE_EXT.
-   The point here is to prepare for future upgrade to 32-bit creation.
-   OTP-19 (erts-8.0) can handle big creation values from other (newer) nodes,
-   but do not use big creation values for the local node yet,
-   as we still may have to communicate with older nodes.
+/*
+ * MAX value for the creation field in pid, port and reference
+ * for the old PID_EXT, PORT_EXT, REFERENCE_EXT and NEW_REFERENCE_EXT.
+ * Older nodes (OTP 19-21) will send us these so we must be able to decode them.
+ *
+ * From OTP 22 DFLAG_BIG_CREATION is mandatory so this node will always
+ * encode with new big 32-bit creations using NEW_PID_EXT, NEW_PORT_EXT
+ * and NEWER_REFERENCE_EXT.
 */
-#define ERTS_MAX_LOCAL_CREATION (3)
-#define is_valid_creation(Cre) ((unsigned)(Cre) <= ERTS_MAX_LOCAL_CREATION)
+#define ERTS_MAX_TINY_CREATION (3)
+#define is_tiny_creation(Cre) ((unsigned)(Cre) <= ERTS_MAX_TINY_CREATION)
 
 #undef ERTS_DEBUG_USE_DIST_SEP
 #ifdef DEBUG
@@ -2520,7 +2519,7 @@ dec_pid(ErtsDistExternal *edep, ErtsHeapFactory* factory, byte* ep,
     if (tag == PID_EXT) {
         cre = get_int8(ep);
         ep += 1;
-        if (!is_valid_creation(cre)) {
+        if (!is_tiny_creation(cre)) {
             return NULL;
         }
     } else {
@@ -3521,7 +3520,7 @@ dec_term_atom_common:
                 if (tag == PORT_EXT) {
                     cre = get_int8(ep);
                     ep++;
-                    if (!is_valid_creation(cre)) {
+                    if (!is_tiny_creation(cre)) {
                         goto error;
                     }
                 }
@@ -3568,7 +3567,7 @@ dec_term_atom_common:
 
 		cre = get_int8(ep);
 		ep += 1;
-		if (!is_valid_creation(cre)) {
+		if (!is_tiny_creation(cre)) {
 		    goto error;
 		}
 		goto ref_ext_common;
@@ -3582,7 +3581,7 @@ dec_term_atom_common:
 
 		cre = get_int8(ep);
 		ep += 1;
-		if (!is_valid_creation(cre)) {
+		if (!is_tiny_creation(cre)) {
 		    goto error;
 		}
 		r0 = get_int32(ep);