Minor comment updates.

From-SVN: r154761

gcc/ada/lib-writ.ads

@@ -157,7 +157,7 @@ package Lib.Writ is
 
    --      One of these lines appears for each of the arguments present in the
    --      call to the gnat1 program. This can be used if it is necessary to
-   --      reconstruct this call (e.g. for fix and continue)
+   --      reconstruct this call (e.g. for fix and continue).
 
    --  -------------------
    --  -- P  Parameters --
@@ -235,7 +235,7 @@ package Lib.Writ is
    --             generated exception tables. If ZX is not present, the
    --             longjmp/setjmp exception scheme is in use.
    --
-   --      Note that language defined units never output policy (Lx,Tx,Qx)
+   --      Note that language defined units never output policy (Lx, Tx, Qx)
    --      parameters. Language defined units must correctly handle all
    --      possible cases. These values are checked for consistency by the
    --      binder and then copied to the generated binder output file.

gcc/ada/prj-tree.ads

@@ -1377,8 +1377,8 @@ package Prj.Tree is
       Key        => Name_Id,
       Hash       => Hash,
       Equal      => "=");
-   --  General type for htables associating name_id to name_id.
-   --  This is in particular used to store the values of external references
+   --  General type for htables associating name_id to name_id. This is in
+   --  particular used to store the values of external references.
 
    type Project_Node_Tree_Data is record
       Project_Nodes : Tree_Private_Part.Project_Node_Table.Instance;

gcc/ada/switch-m.ads

@@ -43,8 +43,9 @@ package Switch.M is
    --  consists of one small letter causes a fatal error exit and control does
    --  not return. For all other not recognized switches, Success is set to
    --  False, so that the switch may be passed to the compiler.
+   --
    --  Project_Node_Tree is used to store tree-specific parameters like the
-   --  project path
+   --  project path.
 
    procedure Normalize_Compiler_Switches
      (Switch_Chars : String;