[Ada] Put_Image improvements for strings

2020-06-15  Bob Duff  <duff@adacore.com>

gcc/ada/

	* exp_attr.adb (Put_Image): Use underlying type for strings.
	Remove unchecked union processing.
	* exp_put_image.adb (Tagged_Put_Image_Enabled): Use -gnatd_z to
	enable default Put_Image for tagged types.  This allows testing
	that feature.
	(Build_String_Put_Image_Call): Set Conversion_OK flag.
	(Make_Component_List_Attributes): Remove unchecked union
	processing.
	(Enable_Put_Image): Disable for unchecked unions.  Enable for
	nonscalar types (which were mistakenly disabled in earlier
	changes).
	* debug.adb: Document -gnatd_z switch.
	* libgnat/s-putima.adb (Put_Image_String, Put_Image_Wide_String,
	Put_Image_Wide_Wide_String): Double double-quote characters.
	Forget about special handling of control characters for now --
	that's rare enough to not be a priority, and it's not clear what
	the right thing to do is anyway.
	* namet.adb: Minor: Improve debugger-friendliness.
	* sinfo.ads: Minor: Add "???" comment.

1 files changed, 9 insertions, 3 deletions

diff --git a/gcc/ada/namet.adb b/gcc/ada/namet.adb
index 60c1050..6cc05bb 100644
--- a/gcc/ada/namet.adb
+++ b/gcc/ada/namet.adb
@@ -1179,11 +1179,13 @@ package body Namet is
       Hash_Index : Hash_Index_Type;
       --  Computed hash index
 
+      Result : Valid_Name_Id;
+
    begin
       --  Quick handling for one character names
 
       if Buf.Length = 1 then
-         return Valid_Name_Id (First_Name_Id + Character'Pos (Buf.Chars (1)));
+         Result := First_Name_Id + Character'Pos (Buf.Chars (1));
 
       --  Otherwise search hash table for existing matching entry
 
@@ -1210,7 +1212,8 @@ package body Namet is
                   end if;
                end loop;
 
-               return New_Id;
+               Result := New_Id;
+               goto Done;
 
                --  Current entry in hash chain does not match
 
@@ -1248,8 +1251,11 @@ package body Namet is
 
          Name_Chars.Append (ASCII.NUL);
 
-         return Name_Entries.Last;
+         Result := Name_Entries.Last;
       end if;
+
+      <<Done>>
+      return Result;
    end Name_Find;
 
    function Name_Find (S : String) return Valid_Name_Id is