Unable to read 0-th character from a string with range checking for zero based strings.

Summary

If reading 0-th character from a string with range checking for zero based strings, a range check error yields.

System Information

  • Operating system: MacOS 14.6.1 (Sonoma)
  • Processor architecture: AARCH64
  • Compiler version: 3.2.2
  • Device: Computer

Steps to reproduce

  1. Open Lazarus, Create a console application project project1.
  2. Paste the code inside project1.lpr:
Program project1;
  {$ZEROBASEDSTRINGS ON}
  {$R+}

Var
  I: Integer;
  S: String;
Begin
  S := 'abc';
  WriteLn(Length(S));
  For I := High(S) Downto Low(S) Do
    WriteLn(I, ' ---> ', S[I]);
End.
  1. Save and build the application.
  2. Open a terminal and run the application using command line.
$ cd /path/to/project1/
$ ./project1

Example Project

What is the current bug behavior?

A runtime error 201 comes up in the terminal window:

3
2 ---> c
1 ---> b
Runtime error 201 at $00000001040A33B0
  $00000001040A33B0

What is the expected (correct) behavior?

No any error, and the result should be like this:

3
2 ---> c
1 ---> b
0 ---> a

Relevant logs and/or screenshots

Possible fixes

Edited by ExSystem