[COMMITTED] ada: Evaluate static expressions in Range attributes

[COMMITTED] ada: Evaluate static expressions in Range attributes

[Marc Poulhiès]

From: Viljar Indus <indus@adacore.com>

Gigi assumes that the value of range expressions is an integer literal.
Force evaluation of such expressions since static non-literal expressions
are not always evaluated to a literal form by gnat.

gcc/ada/

	* sem_attr.adb (analyze_attribute.check_array_type): Replace valid
	indexes with their staticly evaluated values.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/sem_attr.adb | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/gcc/ada/sem_attr.adb b/gcc/ada/sem_attr.adb
index 7a47abdb625..e00addd0152 100644
--- a/gcc/ada/sem_attr.adb
+++ b/gcc/ada/sem_attr.adb
@@ -2013,10 +2013,20 @@ package body Sem_Attr is
                Flag_Non_Static_Expr
                  ("expression for dimension must be static!", E1);
                Error_Attr;
-
-            elsif Expr_Value (E1) > D or else Expr_Value (E1) < 1 then
-               Error_Attr ("invalid dimension number for array type", E1);
             end if;
+
+            declare
+               Value : constant Uint := Expr_Value (E1);
+            begin
+
+               if Value > D or else Value < 1 then
+                  Error_Attr ("invalid dimension number for array type", E1);
+               end if;
+
+               --  Replace the static value to simplify the tree for gigi
+               Fold_Uint (E1, Value, True);
+            end;
+
          end if;
 
          if (Style_Check and Style_Check_Array_Attribute_Index)
-- 
2.40.0