Fix #29935: missing cycles update/crash when removing world datablock form scene.

intern/cycles/blender/blender_object.cpp

@@ -159,6 +159,7 @@ void BlenderSync::sync_background_light()
 {
 	BL::World b_world = b_scene.world();
 
+	if(b_world) {
 		PointerRNA cworld = RNA_pointer_get(&b_world.ptr, "cycles");
 		bool sample_as_light = get_boolean(cworld, "sample_as_light");
 
@@ -179,6 +180,7 @@ void BlenderSync::sync_background_light()
 				light_map.set_recalc(b_world);
 			}
 		}
+	}
 
 	world_map = b_world.ptr.data;
 	world_recalc = false;

source/blender/makesrna/intern/rna_scene.c

@@ -3957,7 +3957,7 @@ void RNA_def_scene(BlenderRNA *brna)
 	prop= RNA_def_property(srna, "world", PROP_POINTER, PROP_NONE);
 	RNA_def_property_flag(prop, PROP_EDITABLE);
 	RNA_def_property_ui_text(prop, "World", "World used for rendering the scene");
-	RNA_def_property_update(prop, NC_SCENE|ND_WORLD, NULL);
+	RNA_def_property_update(prop, NC_SCENE|ND_WORLD, "rna_Scene_glsl_update");
 
 	prop= RNA_def_property(srna, "cursor_location", PROP_FLOAT, PROP_XYZ_LENGTH);
 	RNA_def_property_float_sdna(prop, NULL, "cursor");

source/blender/quicktime/quicktime_export.h

@@ -50,10 +50,11 @@ typedef struct QuicktimeCodecTypeDesc {
 } QuicktimeCodecTypeDesc ;
 
 // quicktime movie output functions
+struct ImageFormatData;
 struct RenderData;
+struct ReportList;
 struct Scene;
 struct wmOperatorType;
-struct ReportList;
 
 int start_qt(struct Scene *scene, struct RenderData *rd, int rectx, int recty, struct ReportList *reports);	//for movie handle (BKE writeavi.c now)
 int append_qt(struct RenderData *rd, int frame, int *pixels, int rectx, int recty, struct ReportList *reports);