(It seems I cannot edit posts once posted.)

I should have said I am on Debian Sid using SCons for building with the ldc2 compiler from Debian packages and the gtkd-3 library from Debian packages. The current output from executing is:

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'quit'.  Did you compile with -rdynamic?

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'refreshFontSize'.  Did you compile with -rdynamic?

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'refreshSampleText'.  Did you compile with -rdynamic?

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'familyListSingleClicked'.  Did you compile with -rdynamic?

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'familyListDoubleClicked'.  Did you compile with -rdynamic?

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'about'.  Did you compile with -rdynamic?

(gfontbrowser:15267): Gtk-WARNING **: Could not find signal handler 'quit'.  Did you compile with -rdynamic?

I have functions:

extern (C) void about(Event e, Widget w) {
	About.about();
}

extern (C) void quit() {
  exit(0);
}

extern (C) void refreshFontSize() {
  writeln("refreshFontSize");
}

extern (C) void refreshSampleText() {
  writeln("refreshSampleText");
}

extern (C) void familyListSingleClicked() {
  writeln("familyListSingleClicked");
}

extern (C) void familyListDoubleClicked() {
  writeln("familyListDoubleClicked");
}

which I had thought would be bound by the call:

builder.connectSignals(null);