Ada: Fix visibility issue on generic parent from nested generic package

The problem is that we temporarily push onto the scope stack and install
the declarations of a package that is already on the scope stack and whose
declarations are already visible so, when the temporary condition is over,
the declarations are uninstalled, thus making them definitively invisible.

It comes from the use of the idiom Scope_Within_Or_Same (Current_Scope, S)
to detect whether S is open in the current scope, but that's not robust in
the presence of transient scopes or during instantiation of generic units.

gcc/ada/
	* sem_ch13.adb (Analyze_Aspects_At_Freeze_Point): Replace call to
	Scope_Within_Or_Same (Current_Scope, S) with In_Open_Scopes (S) to
	test whether S is open in the current scope.
	* sem_util.adb (From_Nested_Package): Likewise.

gcc/testsuite/
	* gnat.dg/generic_inst16.adb: New test.
	* gnat.dg/generic_inst16_pkg.ads: New helper.
	* gnat.dg/generic_inst16_pkg-child.ads: Likewise.
	* gnat.dg/generic_inst16_pkg-child-grandchild.ads: Likewise.
	* gnat.dg/generic_inst16_proc.ads: Likewise.
	* gnat.dg/generic_inst16_proc.adb: Likewise.

diff --git a/gcc/ada/sem_ch13.adb b/gcc/ada/sem_ch13.adb
index 9367d438e58a880577226ba6cbfc3d17e910b016..c569bd6dd378af6ed7d8f90d59fc7b7ee6561e50 100644 (file)
--- a/gcc/ada/sem_ch13.adb
+++ b/gcc/ada/sem_ch13.adb
@@ -1527,9 +1527,7 @@ package body Sem_Ch13 is
       --  at the ends of certain declaration lists (like visible-part lists),
       --  not when this procedure is called at arbitrary freeze points.
 
-      if not Nonoverridable_Only
-        and then not Scope_Within_Or_Same (Current_Scope, Scope (E))
-      then
+      if not Nonoverridable_Only and then not In_Open_Scopes (Scope (E)) then
          if Is_Type (E) and then From_Nested_Package (E) then
             declare
                Pack : constant Entity_Id := Scope (E);

diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 8a7f1774aedb5a0a9a37dff0481794ae74d9dbb3..bce854fddb73e44a94b58e3e83d530a137b40124 100644 (file)
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -9868,7 +9868,7 @@ package body Sem_Util is
       return
         Ekind (Pack) = E_Package
           and then not Is_Frozen (Pack)
-          and then not Scope_Within_Or_Same (Current_Scope, Pack)
+          and then not In_Open_Scopes (Pack)
           and then In_Open_Scopes (Scope (Pack));
    end From_Nested_Package;
 

diff --git a/gcc/testsuite/gnat.dg/generic_inst16.adb b/gcc/testsuite/gnat.dg/generic_inst16.adb
new file mode 100644 (file)
index 0000000..8599001
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/generic_inst16.adb
@@ -0,0 +1,11 @@
+-- { dg-do link }
+
+with Generic_Inst16_Pkg.Child.Grandchild;
+with Generic_Inst16_Proc;
+
+procedure Generic_Inst16 is
+   package   P1 is new Generic_Inst16_Pkg.Child;
+   procedure P2 is new Generic_Inst16_Proc (P1);
+begin
+   null;
+end;

diff --git a/gcc/testsuite/gnat.dg/generic_inst16_pkg-child-grandchild.ads b/gcc/testsuite/gnat.dg/generic_inst16_pkg-child-grandchild.ads
new file mode 100644 (file)
index 0000000..b8e583d
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/generic_inst16_pkg-child-grandchild.ads
@@ -0,0 +1,20 @@
+generic
+package Generic_Inst16_Pkg.Child.Grandchild is
+
+   type CT is new GPT with private;
+
+   Zippo_CT1 : constant CT;
+   Zippo_CT2 : constant CT;
+
+private
+
+   type CT is new PT with
+      record
+         Small_Pi : Natural := 314;
+      end record;
+
+   Zippo_CT1 : constant CT := (Zippo_PT with Small_Pi => 0);
+   Zippo_CT2 : constant CT :=
+     (Generic_Inst16_Pkg.Child.Zippo_PT with Small_Pi => 0);
+
+end Generic_Inst16_Pkg.Child.Grandchild;

diff --git a/gcc/testsuite/gnat.dg/generic_inst16_pkg-child.ads b/gcc/testsuite/gnat.dg/generic_inst16_pkg-child.ads
new file mode 100644 (file)
index 0000000..3a14a35
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/generic_inst16_pkg-child.ads
@@ -0,0 +1,17 @@
+generic
+package Generic_Inst16_Pkg.Child is
+
+   type PT is new GPT with private;
+
+   Zippo_PT : constant PT;
+   
+private
+   
+   type PT is new GPT with
+      record
+         Pos_Pi : Natural := 314159265;
+      end record;
+
+   Zippo_PT : constant PT := (Pos_Pi => 0);
+
+end Generic_Inst16_Pkg.Child;

diff --git a/gcc/testsuite/gnat.dg/generic_inst16_pkg.ads b/gcc/testsuite/gnat.dg/generic_inst16_pkg.ads
new file mode 100644 (file)
index 0000000..ca01215
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/generic_inst16_pkg.ads
@@ -0,0 +1,5 @@
+package Generic_Inst16_Pkg is
+
+   type GPT is interface;
+
+end Generic_Inst16_Pkg;

diff --git a/gcc/testsuite/gnat.dg/generic_inst16_proc.adb b/gcc/testsuite/gnat.dg/generic_inst16_proc.adb
new file mode 100644 (file)
index 0000000..7971b21
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/generic_inst16_proc.adb
@@ -0,0 +1,7 @@
+with Generic_Inst16_Pkg.Child.Grandchild;
+
+procedure Generic_Inst16_Proc is
+   package Inst_Grandchild is new Inst_Child.Grandchild;
+begin
+   null;
+end;

diff --git a/gcc/testsuite/gnat.dg/generic_inst16_proc.ads b/gcc/testsuite/gnat.dg/generic_inst16_proc.ads
new file mode 100644 (file)
index 0000000..bbc120b
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/generic_inst16_proc.ads
@@ -0,0 +1,5 @@
+with Generic_Inst16_Pkg.Child;
+
+generic
+   with package Inst_Child is new Generic_Inst16_Pkg.Child (<>);
+procedure Generic_Inst16_Proc;