Bug#1066945: libglibmm-2.4-dev: Printing Glib::ustring containing non-ascii character throws exception

[Gerardo Ballabio]

Package: libglibmm-2.4-dev
Version: 2.66.5-2
Severity: normal
X-Debbugs-Cc: gerardo.ballabio at gmail.com

Dear Maintainer,

a C++ program of mine, when I tried printing a Glib::ustring that
contained a non-ascii UTF-8 character, threw an exception and aborted.
The following program reproduces the failure:

  #include <iostream>
  #include <iomanip>
  #include <glibmm/ustring.h>

  int main()
  {
    std::cout << std::string("però") << std::endl;   // works
    std::cout << Glib::ustring("pero") << std::endl; // works
    std::cout << Glib::ustring("però") << std::endl; // throws

    return 0;
  }

The third statement generates this error:

  terminate called after throwing an instance of 'Glib::ConvertError'
  Aborted

I thought that the reason why Glib::ustring was created was exactly to
handle UTF-8 characters correctly...

Thanks
Gerardo Ballabio

-- System Information:
Debian Release: 12.4
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 6.1.0-17-amd64 (SMP w/4 CPU threads; PREEMPT)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8),
LANGUAGE=en_US:en
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages libglibmm-2.4-dev depends on:
ii  libglib2.0-dev        2.74.6-2
ii  libglibmm-2.4-1v5     2.66.5-2
ii  libsigc++-2.0-dev     2.12.0-1
ii  pkg-config            1.8.1-1
ii  pkgconf [pkg-config]  1.8.1-1

libglibmm-2.4-dev recommends no packages.

Versions of packages libglibmm-2.4-dev suggests:
pn  libglibmm-2.4-doc  <none>
ii  libgtkmm-3.0-dev   3.24.7-1

-- no debconf information