diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index 98d2def2590..3aaa6d46897 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,14 @@
+2009-04-20  Bob Duff  <duff@adacore.com>
+
+	* sem.adb, gnat1drv.adb, debug.adb: Use the -gnatd.W switch to control
+	debugging output.
+
+2009-04-20  Robert Dewar  <dewar@adacore.com>
+
+	* sem_attr.adb: Minor reformatting
+
+	* gnatcmd.adb: Minor reformatting
+
 2009-04-20  Ed Schonberg  <schonberg@adacore.com>
 
 	* sem_ch4.adb (Analyze_User_Defined_Binary_Op): If left operand is
diff --git a/gcc/ada/debug.adb b/gcc/ada/debug.adb
index 462975607df..8cb47ac5886 100644
--- a/gcc/ada/debug.adb
+++ b/gcc/ada/debug.adb
@@ -140,7 +140,7 @@ package body Debug is
    --  d.T  Force Optimize_Alignment (Time)
    --  d.U
    --  d.V
-   --  d.W
+   --  d.W  Print out debugging information for Walk_Library_Items
    --  d.X
    --  d.Y
    --  d.Z
@@ -559,6 +559,10 @@ package body Debug is
 
    --  d.T  Force Optimize_Alignment (Time) mode as the default
 
+   --  d.W  Print out debugging information for Walk_Library_Items, including
+   --       the order in which units are walked. This is primarily for SofCheck
+   --       Inspector.
+
    --  d1   Error messages have node numbers where possible. Normally error
    --       messages have only source locations. This option is useful when
    --       debugging errors caused by expanded code, where the source location
diff --git a/gcc/ada/gnat1drv.adb b/gcc/ada/gnat1drv.adb
index cb73edf64fd..1dbc6bbb4f5 100644
--- a/gcc/ada/gnat1drv.adb
+++ b/gcc/ada/gnat1drv.adb
@@ -740,9 +740,13 @@ begin
       Namet.Lock;
       Stringt.Lock;
 
-      --  ???pragma Debug (Check_Library_Items);
-      --  Commented out, because it currently does not work if the -gnatn
-      --  switch (back end inlining) is used.
+      --  ???Check_Library_Items under control of a debug flag, because it
+      --  currently does not work if the -gnatn switch (back end inlining) is
+      --  used.
+
+      if Debug_Flag_Dot_WW then
+         Check_Library_Items;
+      end if;
 
       --  Here we call the back end to generate the output code
 
diff --git a/gcc/ada/gnatcmd.adb b/gcc/ada/gnatcmd.adb
index ddb62c58c7c..a412551859e 100644
--- a/gcc/ada/gnatcmd.adb
+++ b/gcc/ada/gnatcmd.adb
@@ -1051,11 +1051,10 @@ procedure GNATCmd is
 
          else
             declare
-               Switch         : constant String :=
-                                  Last_Switches.Table (J).all;
-
-               ALI_File       : constant String (1 .. Switch'Length + 4) :=
-                                  Switch & ".ali";
+               Switch    : constant String :=
+                             Last_Switches.Table (J).all;
+               ALI_File  : constant String (1 .. Switch'Length + 4) :=
+                             Switch & ".ali";
 
                Test_Existence : Boolean := False;
 
diff --git a/gcc/ada/sem.adb b/gcc/ada/sem.adb
index d1d3c91e919..402e17edd75 100644
--- a/gcc/ada/sem.adb
+++ b/gcc/ada/sem.adb
@@ -63,8 +63,8 @@ pragma Warnings (Off, Sem_Util);
 
 package body Sem is
 
-   Debug_Unit_Walk : constant Boolean := False;
-   --  Set to True to print out debugging information for Walk_Library_Items
+   Debug_Unit_Walk : Boolean renames Debug_Flag_Dot_WW;
+   --  Controls debugging printouts for Walk_Library_Items
 
    Outer_Generic_Scope : Entity_Id := Empty;
    --  Global reference to the outer scope that is generic. In a non
@@ -1564,7 +1564,9 @@ package body Sem is
                   Write_Unit_Info (Unit_Num, Item);
                end if;
 
-               --  ??? why is this commented out
+               --  This assertion is commented out because it fails in some
+               --  circumstances related to library-level generic
+               --  instantiations. We need to investigate why.
                --  ???pragma Assert (not Seen (Unit_Num));
 
                Seen (Unit_Num) := True;
diff --git a/gcc/ada/sem_attr.adb b/gcc/ada/sem_attr.adb
index 3e8311b6097..a4478acb94c 100644
--- a/gcc/ada/sem_attr.adb
+++ b/gcc/ada/sem_attr.adb
@@ -6153,12 +6153,11 @@ package body Sem_Attr is
          Ind : Node_Id;
 
       begin
-         --  In the case of a generic index type, the bounds may
-         --  appear static but the computation is not meaningful,
-         --  and may generate a spurious warning.
+         --  In the case of a generic index type, the bounds may appear static
+         --  but the computation is not meaningful in this case, and may
+         --  generate a spurious warning.
 
          Ind := First_Index (P_Type);
-
          while Present (Ind) loop
             if Is_Generic_Type (Etype (Ind)) then
                return;