Use internal exception to get backtraces.

kdesrc-build

@@ -1859,7 +1859,7 @@ HOME
         # ignore file and propagate that information to our context object.
 
         my $path = $self->module()->fullpath('source') . "/build-script-ignore";
-        open my $fh, '<', $path or die "Unable to read ignore data: $!";
+        open my $fh, '<', $path or die make_exception('Internal', "Unable to read ignore data: $!");
 
         my $ctx = $self->module()->buildContext();
         my @ignoreModules = map { chomp $_; $_ } (<$fh>);