ut_runner does not display dialog on crash but dumps the stack trace to stdout.

src/klayout_main/klayout_main/klayout.cc

@@ -24,6 +24,7 @@
 #include "layApplication.h"
 #include "layFileDialog.h"
 #include "layVersion.h"
+#include "laySignalHandler.h"
 #include "tlExceptions.h"
 #include "tlInternational.h"
 #include "tlException.h"
@@ -232,6 +233,7 @@ klayout_main_cont (int &argc, char **argv)
       app.reset (new lay::NonGuiApplication (argc, argv));
     } else {
       app.reset (new lay::GuiApplication (argc, argv));
+      lay::enable_signal_handler_gui (true);
     }
 
     app->parse_cmd (argc, argv);

src/lay/lay/laySignalHandler.cc

@@ -275,6 +275,13 @@ QString get_symbol_name_from_address (const QString &, size_t)
   return QString::fromUtf8 ("n/a");
 }
 
+static bool s_sh_has_gui = false;
+
+void enable_signal_handler_gui (bool en)
+{
+  s_sh_has_gui = en;
+}
+
 void signal_handler (int signo, siginfo_t *si, void *)
 {
   void *array [100];
@@ -292,7 +299,7 @@ void signal_handler (int signo, siginfo_t *si, void *)
 
   std::auto_ptr<CrashMessage> msg;
 
-  bool has_gui = lay::ApplicationBase::instance () && lay::ApplicationBase::instance ()->has_gui ();
+  bool has_gui = s_sh_has_gui && lay::ApplicationBase::instance () && lay::ApplicationBase::instance ()->has_gui ();
 
   if (has_gui) {
     msg.reset (new CrashMessage (0, false, tl::to_qstring (text) + QObject::tr ("\nCollecting backtrace ..")));

src/lay/lay/laySignalHandler.h

@@ -24,6 +24,7 @@
 #define HDR_laySignalHandler
 
 #include <QString>
+#include "layCommon.h"
 
 namespace lay
 {
@@ -38,6 +39,11 @@ void install_signal_handlers ();
  */
 QString get_symbol_name_from_address (const QString &mod_name, size_t addr);
 
+/**
+ *  @brief Enables GUI support for signal handlers
+ */
+void LAY_PUBLIC enable_signal_handler_gui (bool en);
+
 }
 
 #endif