Merge branch 'maint'

* maint:
  compiler alias analysis: Fix bug in status of map extracts

lib/compiler/src/beam_ssa_alias.erl

@@ -658,6 +658,8 @@ aa_derive_from(_Dst, [], _, State0) ->
 aa_derive_from(Dst, Parent, Types, State0) ->
     aa_derive_from1(Dst, Parent, Types, State0).
 
+aa_derive_from1(#b_var{}=Dst, #b_literal{val=Val}, _, State) when is_map(Val) ->
+    aa_set_aliased(Dst, State);
 aa_derive_from1(#b_var{}, #b_literal{}, _, State) ->
     State;
 aa_derive_from1(Dst, Parent, Types, State) ->

lib/compiler/test/beam_ssa_check_SUITE_data/alias.erl

@@ -58,6 +58,7 @@
 	 not_transformable3/1,
 	 not_transformable4/1,
 	 not_transformable5/1,
+	 not_transformable6/0,
 
          bad_get_status_by_type/0,
          stacktrace0/0,
@@ -635,6 +636,17 @@ not_transformable5b([H|T], Acc) ->
 not_transformable5b([], Acc) ->
     Acc.
 
+%% Check that anything extracted from a map is aliased. This is
+%% required as otherwise the destructive update pass could try to
+%% update a literal.
+not_transformable6() ->
+%ssa% () when post_ssa_opt ->
+%ssa% E = get_map_element(...),
+%ssa% _ = bs_create_bin(append, _, E, ...) { aliased => [E], first_fragment_dies => true }.
+    M = #{a=> <<>>},
+    #{a:=X} = M,
+    <<X/binary, 17:8>>.
+
 %% Reproducer for a bug in beam_ssa_alias:aa_get_status_by_type/2
 %% where it would return the wrong alias/uniqe status for certain
 %% combinations of returned types.