RTTI.Invoke string treatment depends on {$H} setting

Summary

With {$H+}, string passed to RTTI.Invoke is accessed correctly. Otherwise, it's like trying to treat a shortstring as an ansistring.

System Information

• Operating system: Linux
• Processor architecture: x86_64
• Compiler version: bb182470
• Device: Laptop

Steps to reproduce

Compile and run the following code:

{$ H+}
uses
  rtti,
  typinfo,
{$ifndef win64}
  ffi.manager;
{$endif}

procedure p(s: String);
begin
  WriteLn(s);
end;

var
  a: TValueArray;
begin
  a := ['hello'];
  Invoke(@p,a,ccReg,nil,false,false);
end.

The output will be garbage like: ello�?@�?� @�?���

Change the {$ H+} into {$H+} and it will output: hello

Example Project

What is the current bug behavior?

Seems like a shortstring is treated as an ansistring

What is the expected (correct) behavior?

With or without {$H+}, it should output: hello

Relevant logs and/or screenshots

Possible fixes

I think this is due to missing operator := definition for shortstring in TValue record, but somehow the compiler managed to think that the shortstring can be treated like an ansistring.

Declaring:

operator := (const AValue: ShortString) Result: TValue; inline;
begin
  TValue.Make(@AValue, System.TypeInfo(AValue), Result);
end;

in above program is sufficient to solve the problem. A proper implementation has been done in the linked merge request, tested and proven to be working.