Fix unitialized variable

DDCore/src/SurfaceInstaller.cpp

@@ -23,7 +23,7 @@ typedef DetElement::Children _C;
 
 /// Initializing constructor
 SurfaceInstaller::SurfaceInstaller(LCDD& lcdd, int argc, char** argv)
-  : m_lcdd(lcdd), m_det()
+  : m_lcdd(lcdd), m_det(), m_stopScanning(false)
 {
   if ( argc > 0 )  {
     string det_name = argv[0];

DDDetectors/compact/SiD_Markus.xml

@@ -235,6 +235,7 @@
    <plugins>
     <plugin name="DD4hep_SiTrackerBarrelSurfacePlugin">
       <argument value="SiTrackerBarrel"/>
+      <argument value="dimension=1"/>
     </plugin>
     <plugin name="DD4hep_SurfaceExamplePlugin">
       <argument value="SiTrackerBarrel"/>