diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index a8b179ac894..84e7e8549c9 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,7 @@
+2010-01-25  Bob Duff  <duff@adacore.com>
+
+	* exp_ch4.adb, exp_aggr.adb: Minor comment fixes and code clean up.
+
 2010-01-25  Arnaud Charlet  <charlet@adacore.com>
 
 	* gnatvsn.ads (Current_Year): Update.
diff --git a/gcc/ada/exp_aggr.adb b/gcc/ada/exp_aggr.adb
index 49e681b9ed9..6e3edc192b9 100644
--- a/gcc/ada/exp_aggr.adb
+++ b/gcc/ada/exp_aggr.adb
@@ -2578,7 +2578,7 @@ package body Exp_Aggr is
                Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
                Set_Assignment_OK (Ref);
 
-               if not Is_Abstract_Type (Init_Typ) then
+               if not Is_Interface (Init_Typ) then
                   Append_List_To (L,
                     Build_Initialization_Call (Loc,
                       Id_Ref            => Ref,
@@ -3681,7 +3681,7 @@ package body Exp_Aggr is
       --  total number of components is safe enough to expand.
 
       function Is_Flat (N : Node_Id; Dims : Int) return Boolean;
-      --  Return True iff the array N is flat (which is not rivial in the case
+      --  Return True iff the array N is flat (which is not trivial in the case
       --  of multidimensionsl aggregates).
 
       -----------------------------
@@ -3919,7 +3919,7 @@ package body Exp_Aggr is
                      end if;
                   end if;
 
-                  --  Range cases merge with Lo,Hi said
+                  --  Range cases merge with Lo,Hi set
 
                   if not Compile_Time_Known_Value (Lo)
                        or else
diff --git a/gcc/ada/exp_ch4.adb b/gcc/ada/exp_ch4.adb
index 4f0ef91a419..096abbde9c9 100644
--- a/gcc/ada/exp_ch4.adb
+++ b/gcc/ada/exp_ch4.adb
@@ -5101,9 +5101,10 @@ package body Exp_Ch4 is
          Cnode := Left_Opnd (Cnode);
       end loop;
 
-      --  Now Opnd is the deepest Opnd, and its parents are the concatenation
-      --  nodes above, so now we process bottom up, doing the operations. We
-      --  gather a string that is as long as possible up to five operands
+      --  Now Cnode is the deepest concatenation, and its parents are the
+      --  concatenation nodes above, so now we process bottom up, doing the
+      --  operations. We gather a string that is as long as possible up to five
+      --  operands.
 
       --  The outer loop runs more than once if more than one concatenation
       --  type is involved.