[Ada] Spurious error on inst. of partially defaulted formal package

This patch removes a spurious error on an instantiation whose generic
unit has a formal package where some formal parameters are
box-initialiaed.  Previously the code assumed that box-initialization
for a formal package applied to all its formal parameters.

2019-07-01  Ed Schonberg  <schonberg@adacore.com>

gcc/ada/

	* sem_ch12.adb (Is_Defaulted): New predicate in
	Check_Formal_Package_Intance, to skip the conformance of checks
	on parameters of a formal package that are defaulted,

gcc/testsuite/

	* gnat.dg/generic_inst3.adb,
	gnat.dg/generic_inst3_kafka_lib-topic.ads,
	gnat.dg/generic_inst3_kafka_lib.ads,
	gnat.dg/generic_inst3_markets.ads,
	gnat.dg/generic_inst3_traits-encodables.ads,
	gnat.dg/generic_inst3_traits.ads: New testcase.

From-SVN: r272883

gcc/ada/ChangeLog

+2019-07-01  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_ch12.adb (Is_Defaulted): New predicate in
+	Check_Formal_Package_Intance, to skip the conformance of checks
+	on parameters of a formal package that are defaulted,
+
 2019-07-01  Hristian Kirtchev  <kirtchev@adacore.com>
 
 	* checks.adb, exp_ch9.adb, exp_unst.adb, sem_ch4.adb,

gcc/ada/sem_ch12.adb

@@ -6195,6 +6195,12 @@ package body Sem_Ch12 is
       --  Common error routine for mismatch between the parameters of the
       --  actual instance and those of the formal package.
 
+      function Is_Defaulted (Param : Entity_Id) return Boolean;
+      --  If the formql package has partly box-initialized formals, skip
+      --  conformace check for these formals. Previously the code assumed
+      --  that boc initialization for a formal package applied to all
+      --  its formal parameters.
+
       function Same_Instantiated_Constant (E1, E2 : Entity_Id) return Boolean;
       --  The formal may come from a nested formal package, and the actual may
       --  have been constant-folded. To determine whether the two denote the
@@ -6245,6 +6251,32 @@ package body Sem_Ch12 is
          end if;
       end Check_Mismatch;
 
+      ------------------
+      -- Is_Defaulted --
+      ------------------
+
+      function Is_Defaulted (Param : Entity_Id) return Boolean is
+         Assoc : Node_Id;
+      begin
+         Assoc := First (Generic_Associations
+                     (Parent (Associated_Formal_Package (Actual_Pack))));
+
+         while Present (Assoc) loop
+            if Nkind (Assoc) = N_Others_Choice then
+               return True;
+
+            elsif Nkind (Assoc) = N_Generic_Association
+              and then Chars (Selector_Name (Assoc)) = Chars (Param)
+            then
+               return Box_Present (Assoc);
+            end if;
+
+            Next (Assoc);
+         end loop;
+
+         return False;
+      end Is_Defaulted;
+
       --------------------------------
       -- Same_Instantiated_Constant --
       --------------------------------
@@ -6414,6 +6446,9 @@ package body Sem_Ch12 is
          then
             goto Next_E;
 
+         elsif Is_Defaulted (E1) then
+            goto Next_E;
+
          elsif Is_Type (E1) then
 
             --  Subtypes must statically match. E1, E2 are the local entities

gcc/testsuite/ChangeLog

 2019-07-01  Ed Schonberg  <schonberg@adacore.com>
 
+	* gnat.dg/generic_inst3.adb,
+	gnat.dg/generic_inst3_kafka_lib-topic.ads,
+	gnat.dg/generic_inst3_kafka_lib.ads,
+	gnat.dg/generic_inst3_markets.ads,
+	gnat.dg/generic_inst3_traits-encodables.ads,
+	gnat.dg/generic_inst3_traits.ads: New testcase.
+
+2019-07-01  Ed Schonberg  <schonberg@adacore.com>
+
 	* gnat.dg/enum_rep.adb, gnat.dg/enum_rep.ads: New testcase.
 
 2019-07-01  Ed Schonberg  <schonberg@adacore.com>

gcc/testsuite/gnat.dg/generic_inst3.adb

+--  { dg-do compile }
+
+with Generic_Inst3_Kafka_Lib.Topic;
+with Generic_Inst3_Traits.Encodables;
+with Generic_Inst3_Markets;
+
+procedure Generic_Inst3 is
+   generic
+      with package Values is new Generic_Inst3_Traits.Encodables (<>);
+      with package Topic is new Generic_Inst3_Kafka_Lib.Topic
+          (Values => Values, others => <>);
+   package Dummy is
+   end Dummy;
+
+   package Inst is new Dummy
+      (Values => Generic_Inst3_Markets.Data_Encodables,
+       Topic  => Generic_Inst3_Markets.Data_Topic);
+begin
+   null;
+end Generic_Inst3;

gcc/testsuite/gnat.dg/generic_inst3_kafka_lib-topic.ads

+with Generic_Inst3_Traits.Encodables;
+generic
+   Topic_Name : String;
+   with package Keys is new Generic_Inst3_Traits.Encodables (<>);
+   with package Values is new Generic_Inst3_Traits.Encodables (<>);
+package Generic_Inst3_Kafka_Lib.Topic is
+end Generic_Inst3_Kafka_Lib.Topic;

gcc/testsuite/gnat.dg/generic_inst3_kafka_lib.ads

+package Generic_Inst3_Kafka_Lib is
+end Generic_Inst3_Kafka_Lib;

gcc/testsuite/gnat.dg/generic_inst3_markets.ads

+with Generic_Inst3_Kafka_Lib.Topic;
+with Generic_Inst3_Traits.Encodables;
+package Generic_Inst3_Markets is
+   type Data_Type is null record;
+   function Image (D : Data_Type) return String is ("");
+   package Data_Encodables is new Generic_Inst3_Traits.Encodables (Data_Type, Image);
+   package Data_Topic is new Generic_Inst3_Kafka_Lib.Topic
+      (Keys => Data_Encodables, Values => Data_Encodables,
+       Topic_Name => "bla");
+end Generic_Inst3_Markets;

gcc/testsuite/gnat.dg/generic_inst3_traits-encodables.ads

+with Ada.Streams;
+generic
+   pragma Warnings (Off, "is not referenced");
+   type T (<>) is private;
+   with function Image (Val : in T) return String;
+package Generic_Inst3_Traits.Encodables is
+   pragma Pure;
+end Generic_Inst3_Traits.Encodables;

gcc/testsuite/gnat.dg/generic_inst3_traits.ads

+package Generic_Inst3_Traits is
+   pragma Pure;
+end Generic_Inst3_Traits;