无界字符串“ENCODING_ERROR：项目输入错误”

Question

为什么以下代码失败？

我故意选择了

Characters.Latin_1.Reserved_128

。

-- File 'print_non_graphic_character.adb'
with Ada.Characters.Latin_1;
with Ada.Text_IO;
with Ada.Strings.Unbounded;

procedure Print_Non_Graphic_Character is
   Text_String : constant String := "Non Graphic Character: " & Ada.Characters.Latin_1.Reserved_128;
   Text_Unbounded_String : constant Ada.Strings.Unbounded.Unbounded_String :=
      Ada.Strings.Unbounded.To_Unbounded_String (Text_String);
begin
   Ada.Text_IO.Put_Line (Text_String);
   Ada.Text_IO.Put_Line (Ada.Strings.Unbounded.To_String (Text_Unbounded_String));
   Ada.Text_IO.Put_Line (Text_Unbounded_String'Image);
end Print_Non_Graphic_Character;

请注意，它也会失败：

Ada.Text_IO.Put_Line (Ada.Strings.Unbounded.Unbounded_String'Image (Text_Unbounded_String));

-- File 'print_non_graphic_character.gpr'
project Print_Non_Graphic_Character is
   for Main use ("print_non_graphic_character.adb");
   for Object_Dir use ".objs";

   package Compiler is
      -- "-Og" -- Optimize for debug
      -- "-g" -- Generate debug info
      for Default_Switches ("Ada") use ("-g", "-gnat2020", "-Og");
   end Compiler;

   package Binder is
      for Switches ("Ada") use ("-Es"); --  Symbolic traceback
   end Binder;
end Print_Non_Graphic_Character;

它为我提供了 GNAT 12.2.0

Non Graphic Character: �
Non Graphic Character: �

raised ADA.STRINGS.UTF_ENCODING.ENCODING_ERROR : bad input at Item (25)
[./non_graphic_character/.objs/print_non_graphic_character]
0x40e8fb Ada.Strings.Utf_Encoding.Raise_Encoding_Error at a-stuten.adb:126
0x40f38b Ada.Strings.Utf_Encoding.Strings.Decode at a-suenst.adb:163
0x4049a8 Print_Non_Graphic_Character at print_non_graphic_character.adb:13
0x404efa Main at b__print_non_graphic_character.adb:279
[/lib/x86_64-linux-gnu/libc.so.6]
0x7f5e62118d08
[./non_graphic_character/.objs/print_non_graphic_character]
0x404658 _start at ???
0xfffffffffffffffe

这很烦人，因为当我想打印由

Unbounded_String

组成的记录时，由于上述错误，我无法使用

'Image

属性，并且必须打印每个字段并使用

To_String

来表示

Unbounded_String

(当我将其与通用函数/包结合起来时，这很烦人）。

Answer 1

我在 GCC Bugzilla 上打开了一个错误：https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111945.