Merge branch 'lukas/erts/float_encoding/OTP-11738'

* lukas/erts/float_encoding/OTP-11738:
  erts: Set default external enc to use new float scheme

4 files changed, 14 insertions, 12 deletions

diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml
index e440a3d270..aeded7c719 100644
--- a/erts/doc/src/erlang.xml
+++ b/erts/doc/src/erlang.xml
@@ -6589,11 +6589,12 @@ ok
           some details of the encoding. This option was
           introduced in R11B-4. Currently, the allowed values for <c><anno>Version</anno></c>
           are <c>0</c> and <c>1</c>.</p>
-        <p><c>{minor_version, 1}</c> forces any floats in the term to be encoded
+        <p><c>{minor_version, 1}</c> is since 17.0 the default, it forces any floats in
+	  the term to be encoded
           in a more space-efficient and exact way (namely in the 64-bit IEEE format,
           rather than converted to a textual representation). <c>binary_to_term/1</c>
-          in R11B-4 and later is able decode the new representation.</p>
-        <p><c>{minor_version, 0}</c> is currently the default, meaning that floats
+          in R11B-4 and later is able decode this representation.</p>
+        <p><c>{minor_version, 0}</c> meaning that floats
           will be encoded using a textual representation; this option is useful if
           you want to ensure that releases prior to R11B-4 can decode resulting
           binary.</p>
diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index ff8f5e106f..0519a9225e 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -44,6 +44,7 @@
 /* All flags that should be enabled when term_to_binary/1 is used. */
 #define TERM_TO_BINARY_DFLAGS (DFLAG_EXTENDED_REFERENCES	\
 			       | DFLAG_NEW_FUN_TAGS		\
+			       | DFLAG_NEW_FLOATS		\
 			       | DFLAG_EXTENDED_PIDS_PORTS	\
 			       | DFLAG_EXPORT_PTR_TAG		\
 			       | DFLAG_BIT_BINARIES)
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index 9fb2dbd8bf..b8e6b3b072 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -529,7 +529,7 @@ Uint erts_encode_ext_size(Eterm term)
 
 Uint erts_encode_ext_size_2(Eterm term, unsigned dflags)
 {
-    return encode_size_struct2(NULL, term, TERM_TO_BINARY_DFLAGS|dflags)
+    return encode_size_struct2(NULL, term, dflags)
         + 1 /* VERSION_MAGIC */;
 }
 
@@ -1099,10 +1099,10 @@ BIF_RETTYPE term_to_binary_2(BIF_ALIST_2)
 	    if (tp[1] == am_minor_version && is_small(tp[2])) {
 		switch (signed_val(tp[2])) {
 		case 0:
-		    flags = TERM_TO_BINARY_DFLAGS;
+		    flags = TERM_TO_BINARY_DFLAGS & ~DFLAG_NEW_FLOATS;
 		    break;
 		case 1:
-		    flags = TERM_TO_BINARY_DFLAGS|DFLAG_NEW_FLOATS;
+		    flags = TERM_TO_BINARY_DFLAGS;
 		    break;
 		default:
 		    goto error;
@@ -1605,9 +1605,9 @@ external_size_2(BIF_ALIST_2)
             if (tp[1] == am_minor_version && is_small(tp[2])) {
                 switch (signed_val(tp[2])) {
                 case 0:
+                    flags &= ~DFLAG_NEW_FLOATS;
                     break;
                 case 1:
-                    flags |= DFLAG_NEW_FLOATS;
                     break;
                 default:
                     goto error;
diff --git a/erts/emulator/test/binary_SUITE.erl b/erts/emulator/test/binary_SUITE.erl
index a390c536bb..938aac6a0e 100644
--- a/erts/emulator/test/binary_SUITE.erl
+++ b/erts/emulator/test/binary_SUITE.erl
@@ -474,16 +474,16 @@ terms_compression_levels(_, _, _) -> ok.
 
 terms_float(Config) when is_list(Config) ->
     ?line test_floats(fun(Term) ->
-			      Bin0 = term_to_binary(Term),
 			      Bin0 = term_to_binary(Term, [{minor_version,0}]),
 			      Term = binary_to_term_stress(Bin0),
+			      Bin1 = term_to_binary(Term),
 			      Bin1 = term_to_binary(Term, [{minor_version,1}]),
 			      Term = binary_to_term_stress(Bin1),
 			      true = size(Bin1) < size(Bin0),
-                  Size0 = erlang:external_size(Term),
-                  Size00 = erlang:external_size(Term, [{minor_version, 0}]),
-                  Size1 = erlang:external_size(Term, [{minor_version, 1}]),
-                  true = (Size0 =:= Size00),
+                  Size0 = erlang:external_size(Term, [{minor_version, 0}]),
+                  Size1 = erlang:external_size(Term),
+                  Size11 = erlang:external_size(Term, [{minor_version, 1}]),
+                  true = (Size1 =:= Size11),
                   true = Size1 < Size0
 		      end).