[Ada] Plug small loophole with pathological packed array type

This fixes a crash in gigi on a pathological packed array type, whose
component type is a record type without representation clause or packing
but with a clause that bumps its size to a non-multiple value of the
storage unit.  In this case, the front-end fails to detect that calls
to the packing manpulation routines of the run time are necessary.

The fix doesn't change anything for non-pathological cases, i.e. when
the component type has a representation clause or is packed.

2018-12-11  Eric Botcazou  <ebotcazou@adacore.com>

gcc/ada/

	* exp_aggr.adb (Packed_Array_Aggregate_Handled): Bail out for
	any non-scalar type as component type of the array.

gcc/testsuite/

	* gnat.dg/packed_array.adb, gnat.dg/packed_array.ads,
	gnat.dg/packed_array_pkg.ads: New testcase.

From-SVN: r267006

gcc/ada/ChangeLog

 2018-12-11  Eric Botcazou  <ebotcazou@adacore.com>
 
+	* exp_aggr.adb (Packed_Array_Aggregate_Handled): Bail out for
+	any non-scalar type as component type of the array.
+
+2018-12-11  Eric Botcazou  <ebotcazou@adacore.com>
+
 	* einfo.ads (Is_Bit_Packed_Array): Fix values of component size.
 	(Is_Packed): Likewise.
 	* gcc-interface/utils.c (convert): Do not extract the value of a

gcc/ada/exp_aggr.adb

@@ -7893,9 +7893,7 @@ package body Exp_Aggr is
          return False;
       end if;
 
-      if not Is_Scalar_Type (Component_Type (Typ))
-        and then Has_Non_Standard_Rep (Component_Type (Typ))
-      then
+      if not Is_Scalar_Type (Ctyp) then
          return False;
       end if;
 

gcc/testsuite/ChangeLog

+2018-12-11  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/packed_array.adb, gnat.dg/packed_array.ads,
+	gnat.dg/packed_array_pkg.ads: New testcase.
+
 2018-12-11  Hristian Kirtchev  <kirtchev@adacore.com>
 
 	* gnat.dg/ghost3.adb, gnat.dg/ghost3.ads: New testcase.

gcc/testsuite/gnat.dg/packed_array.adb

+package body Packed_Array is
+
+  procedure Dummy is null;
+
+end;

gcc/testsuite/gnat.dg/packed_array.ads

+with Packed_Array_Pkg; use Packed_Array_Pkg;
+
+package Packed_Array is
+
+  C : constant Small_Rec2 := (Lo => 1, Hi => Max, A => (1 => (2, 3)));
+
+  procedure Dummy;
+
+end;

gcc/testsuite/gnat.dg/packed_array_pkg.ads

+package Packed_Array_Pkg is
+
+  type Rec1 is record
+    I : Integer;
+    S : Short_Integer;
+  end record;
+  for Rec1'Size use 49;
+
+  type Arr is array (Positive range <>) of Rec1;
+  for Arr'Component_Size use 49;
+
+  type Rec2 (Lo, Hi : Positive) is record
+    A : Arr (Lo .. Hi);
+  end record;
+
+  Max : Positive := 1;
+
+  subtype Small_Rec2 is Rec2 (1, Max);
+
+end;