Fix gcc 8 warnings

src/client/GameSave.cpp

@@ -270,7 +270,7 @@ char * GameSave::Serialise(unsigned int & dataSize)
 	{
 		return serialiseOPS(dataSize);
 	}
-	catch (BuildException e)
+	catch (BuildException & e)
 	{
 		std::cout << e.what() << std::endl;
 		return NULL;

src/graphics/Renderer.cpp

@@ -2648,8 +2648,8 @@ Renderer::Renderer(Graphics * g, Simulation * sim):
 	renderModePresets[10].ColourMode = COLOUR_LIFE;
 
 	//Prepare the graphics cache
-	graphicscache = (gcache_item *)malloc(sizeof(gcache_item)*PT_NUM);
-	memset(graphicscache, 0, sizeof(gcache_item)*PT_NUM);
+	graphicscache = new gcache_item[PT_NUM];
+	std::fill(&graphicscache[0], &graphicscache[PT_NUM], gcache_item());
 
 	int fireColoursCount = 4;
 	pixel fireColours[] = {PIXPACK(0xAF9F0F), PIXPACK(0xDFBF6F), PIXPACK(0x60300F), PIXPACK(0x000000)};
@@ -2960,7 +2960,7 @@ Renderer::~Renderer()
 	delete[] persistentVid;
 	delete[] warpVid;
 #endif
-	free(graphicscache);
+	delete[] graphicscache;
 	free(flm_data);
 	free(plasma_data);
 }

src/gui/search/SearchView.cpp

@@ -31,7 +31,7 @@ SearchView::SearchView():
 	{
 		motdLabel  = new ui::RichLabel(ui::Point(51, WINDOWH-18), ui::Point(WINDOWW-102, 16), Client::Ref().GetMessageOfTheDay());
 	}
-	catch (std::exception e) { }
+	catch (std::exception & e) { }
 
 	class PageNumAction : public ui::TextboxAction
 	{
@@ -254,7 +254,7 @@ void SearchView::NotifyMessageOfTheDay(Client * sender)
 		{
 			motdLabel->SetText(sender->GetMessageOfTheDay());
 		}
-		catch (std::exception e)
+		catch (std::exception & e)
 		{
 			motdLabel = nullptr;
 		}

src/lua/LegacyLuaAPI.cpp

@@ -238,7 +238,7 @@ int luacon_elementwrite(lua_State* l)
 
 	luacon_model->BuildMenus();
 	luacon_sim->init_can_move();
-	memset(luacon_ren->graphicscache, 0, sizeof(gcache_item)*PT_NUM);
+	std::fill(&luacon_ren->graphicscache[0], &luacon_ren->graphicscache[PT_NUM], gcache_item());
 
 	return 0;
 }

src/simulation/Simulation.cpp

@@ -43,7 +43,7 @@ int Simulation::Load(int fullX, int fullY, GameSave * save, bool includePressure
 	{
 		save->Expand();
 	}
-	catch (ParseException)
+	catch (ParseException &)
 	{
 		return 1;
 	}