Coverity fixes

151677
151789  - OK as is
152005
152508
154871  - false positive
156593
163235

src/Mod/TechDraw/Gui/CommandCreateDims.cpp

@@ -383,6 +383,7 @@ void CmdTechDrawNewDiameterDimension::activated(int iMsg)
     Base::Reference<ParameterGrp> hGrp = App::GetApplication().GetUserParameter()
         .GetGroup("BaseApp")->GetGroup("Preferences")->GetGroup("Mod/TechDraw/Dimensions");
     std::string diamSym = hGrp->GetASCII("DiameterSymbol","\xe2\x8c\x80");
+    diamSym = diamSym.substr (0,79);                                            //coverity 156593
     const char * format = "%value%";
     char formatSpec[80];
     std::strcpy (formatSpec,diamSym.c_str());

src/Mod/TechDraw/Gui/QGIHighlight.cpp

@@ -41,6 +41,7 @@ using namespace TechDrawGui;
 
 QGIHighlight::QGIHighlight()
 {
+    m_refText = "";
     m_refSize = 0.0;
     m_circle = new QGraphicsEllipseItem();
     addToGroup(m_circle);

src/Mod/TechDraw/Gui/QGISectionLine.cpp

@@ -41,6 +41,9 @@ using namespace TechDrawGui;
 
 QGISectionLine::QGISectionLine()
 {
+    m_symbol = "";
+    m_symSize = 0.0;
+    
     m_extLen = Rez::guiX(8.0);
     m_arrowSize = 0.0;
 

src/Mod/TechDraw/Gui/TaskProjGroup.cpp

@@ -279,7 +279,7 @@ void TaskProjGroup::nearestFraction(double val, int &n, int &d) const
 
     n = 1;  // numerator
     d = 1;  // denominator
-    double fraction = n / d;
+    double fraction = 1.0;                                                      //coverity 152005
     //double m = fabs(fraction - val);
 
     while (fabs(fraction - val) > 0.001) {