lldb on BeagleBone Black

[Dr. Rolf Jansen]

> Am 29.05.2017 um 12:08 schrieb Ed Maste <emaste at freebsd.org>:
> 
> On 28 May 2017 at 10:34, Dr. Rolf Jansen <rj at obsigna.com> wrote:
>> This is only a follow-up notice.
>> 
>> I reliably managed to build (lldb + clang/lld) from the svn trunk of LLVM 5.0.0 on my Beaglebone Black running the latest snapshot (May 20th) of FreeBSD 12.0-CURRENT, and the lldb is working very well, and this includes single stepping and ncurses-GUI mode, while single stepping with the latest lldb 4.0.1 from the ports does not work.
> 
> Thanks for the follow-up, and for your persistence in trying to build
> LLDB on the BBB!
> 
> In what way is the UTF-8 output broken?

First of all, my system's locale is:

LANG=en_US.UTF-8
LC_CTYPE="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_ALL=

$echo $TERM
xterm-256color


Now, please consider the following tiny ncurses test program 'cursutf8.c', which prints out the traditional German pangram for testing the special characters 'ä', 'ö', 'ü', 'ß', each of which consists of two bytes when encoded in UTF8:

#include <stdio.h>
#include <locale.h>
#include <curses.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
   setlocale(LC_CTYPE, "");

   WINDOW *window = initscr();
   if (window)
   {
      mvaddstr(3, 3, "Zwölf Boxkämpfer jagen Viktor quer über den großen Sylter Deich.");
      refresh();
      sleep(3);

      delwin(window);
      endwin();
      refresh();

      return 0;
   }

   else
      return 1;
}


I compile this using:
   $clang -g -O0 cursutf8.c -lncursesw -o cursutf8


When I run it, it correctly prints out:
   Zwölf Boxkämpfer jagen Viktor quer über den großen Sylter Deich.


Then I start this with lldb:

$lldb -- cursutf8

(lldb) breakpoint set -f cursutf8.c -l 13
(lldb) run

Process 13886 stopped
* thread #1, name = 'cursutf8', stop reason = breakpoint 1.1
    frame #0: 0x00008a08 cursutf8`main(argc=1, argv=0xbfbfec74) at cursutf8.c:13
   10  	   WINDOW *window = initscr();
   11  	   if (window)
   12  	   {
-> 13  	      mvaddstr(3, 3, "Zwölf Boxkämpfer jagen Viktor quer über den großen Sylter Deich.");
   14  	      refresh();
   15  	      sleep(3);
   16  	

So far this is OK as well.


The issue shows up, when I enter into the GUI mode:

(lldb) gui

│ 10 │    WINDOW *window = initscr();                                                                               
│ 11 │    if (window)                                                                                               
│ 12 │    {                                                                                                         
│ 13 │◆      mvaddstr(3, 3, "ZwM-CM-6lf BoxkM-CM-$mpfer jagen Viktor quer M-CM-<ber den groM-C~_en Sylter Deich."); 
│ 14 │       refresh();                                                                                             
│ 15 │       sleep(3);                                                                                              
│ 16 │


CONCLUSION:

Within LLDB on x86, utf8 text is displayed well in CLI and in GUI mode.

Within LLDB on ARMv6, utf8 test is displayed correctly in CLI but NOT in curse-GUI mode.

A simple ncurses program as such, can handle utf8 text correctly on ARM and x86.

Best regards

Rolf