diff --git a/source/blender/include/BDR_sculptmode.h b/source/blender/include/BDR_sculptmode.h
index cf58d711801..7272df21aa3 100644
--- a/source/blender/include/BDR_sculptmode.h
+++ b/source/blender/include/BDR_sculptmode.h
@@ -89,13 +89,13 @@ typedef struct SculptSession {
 	vec3f pivot;
 } SculptSession;
 
-SculptSession *sculpt_session();
-struct SculptData *sculpt_data();
+SculptSession *sculpt_session(void);
+struct SculptData *sculpt_data(void);
 
 /* Memory */
 void sculptmode_init(struct Scene *);
 void sculptmode_free_all(struct Scene *);
-void sculptmode_correct_state();
+void sculptmode_correct_state(void);
 
 /* Undo */
 typedef enum SculptUndoType {
@@ -105,9 +105,10 @@ typedef enum SculptUndoType {
 	SUNDO_MRES= 8  /* Mesh.mr changed */
 } SculptUndoType;
 void sculptmode_undo_push(char *str, SculptUndoType type);
-void sculptmode_undo();
-void sculptmode_redo();
-void sculptmode_undo_menu();
+void sculptmode_undo(void);
+void sculptmode_redo(void);
+void sculptmode_undo_menu(void);
+void sculptmode_undo_free(struct Scene *sce);
 
 /* Interface */
 void sculptmode_draw_interface_tools(struct uiBlock *block,unsigned short cx, unsigned short cy);
@@ -115,17 +116,17 @@ void sculptmode_draw_interface_textures(struct uiBlock *block,unsigned short cx,
 void sculptmode_rem_tex(void*,void*);
 void sculptmode_propset_init(PropsetMode mode);
 void sculptmode_propset(const unsigned short event);
-void sculptmode_selectbrush_menu();
+void sculptmode_selectbrush_menu(void);
 void sculptmode_draw_mesh(int);
 void sculpt_paint_brush(char clear);
 
-struct BrushData *sculptmode_brush();
-float *get_tex_angle();
+struct BrushData *sculptmode_brush(void);
+float *get_tex_angle(void);
 
-void sculptmode_update_tex();
+void sculptmode_update_tex(void);
 char sculpt_modifiers_active(struct Object *ob);
-void sculpt();
-void set_sculptmode();
+void sculpt(void);
+void set_sculptmode(void);
 
 /* Partial Mesh Visibility */
 struct PartialVisibility *sculptmode_copy_pmv(struct PartialVisibility *);
diff --git a/source/blender/src/editobject.c b/source/blender/src/editobject.c
index 836518964b8..0a74f65c619 100644
--- a/source/blender/src/editobject.c
+++ b/source/blender/src/editobject.c
@@ -1696,6 +1696,9 @@ void exit_editmode(int flag)	/* freedata==0 at render, 1= freedata, 2= do undo b
 			allqueue(REDRAWIMAGE, 0);
 		if(G.f & G_WEIGHTPAINT)
 			mesh_octree_table(G.obedit, NULL, 'e');
+		/* to be sure, adding/removing data crashes undo for sculpt (ton) */
+		if(G.f & G_SCULPTMODE)
+			sculptmode_undo_free(G.scene);
 	}
 	else if (G.obedit->type==OB_ARMATURE){	
 		load_editArmature();
diff --git a/source/blender/src/sculptmode.c b/source/blender/src/sculptmode.c
index ac03d36e1cb..2a00287426e 100644
--- a/source/blender/src/sculptmode.c
+++ b/source/blender/src/sculptmode.c
@@ -161,13 +161,14 @@ typedef struct ProjVert {
 static ProjVert *projverts= NULL;
 static Object *active_ob= NULL;
 
-SculptData *sculpt_data()
+SculptData *sculpt_data(void)
 {
 	return &G.scene->sculptdata;
 }
 
-void sculpt_init_session();
-SculptSession *sculpt_session()
+void sculpt_init_session(void);
+
+SculptSession *sculpt_session(void)
 {
 	if(!sculpt_data()->session)
 		sculpt_init_session();
@@ -212,7 +213,7 @@ void sculptmode_init(Scene *sce)
 
 void sculptmode_undo_init();
 void sculptmode_free_session(Scene *);
-void sculpt_init_session()
+void sculpt_init_session(void)
 {
 	if(sculpt_data()->session)
 		sculptmode_free_session(G.scene);
@@ -336,6 +337,7 @@ void sculptmode_undo_pull_chopped(SculptUndoStep *sus)
 		}
 }
 
+/* also called now after leave mesh editmode. prevent crashing when data amount changes */
 void sculptmode_undo_free(Scene *sce)
 {
 	SculptSession *ss= sce->sculptdata.session;
@@ -508,7 +510,7 @@ void sculptmode_undo_update(SculptUndoStep *newcur)
 	allqueue(REDRAWBUTSEDIT, 0);
 }
 
-void sculptmode_undo()
+void sculptmode_undo(void)
 {
 	SculptUndo *su= sculpt_session()->undo;
 
@@ -516,7 +518,7 @@ void sculptmode_undo()
 		sculptmode_undo_update(su->cur->prev);
 }
 
-void sculptmode_redo()
+void sculptmode_redo(void)
 {
 	SculptUndo *su= sculpt_session()->undo;
 
@@ -524,7 +526,7 @@ void sculptmode_redo()
 		sculptmode_undo_update(su->cur->next);
 }
 
-void sculptmode_undo_menu()
+void sculptmode_undo_menu(void)
 {
 	SculptUndo *su= sculpt_session()->undo;
 	SculptUndoStep *sus;
@@ -1004,7 +1006,7 @@ unsigned *get_ri_pixel(const RenderInfo *ri, int px, int py)
 }
 
 /* Use the warpfac field in MTex to store a rotation value for sculpt textures. */
-float *get_tex_angle()
+float *get_tex_angle(void)
 {
 	SculptData *sd= sculpt_data();
 	if(sd->texact!=-1 && sd->mtex[sd->texact])
@@ -1326,7 +1328,7 @@ void calc_damaged_verts(ListBase *damaged_verts, GrabData *grabdata)
 	}
 }
 
-BrushData *sculptmode_brush()
+BrushData *sculptmode_brush(void)
 {
 	SculptData *sd= &G.scene->sculptdata;
 	return (sd->brush_type==DRAW_BRUSH ? &sd->drawbrush :
@@ -1694,7 +1696,7 @@ void sculptmode_propset(unsigned short event)
 	sculptmode_propset_header();
 }
 
-void sculptmode_selectbrush_menu()
+void sculptmode_selectbrush_menu(void)
 {
 	SculptData *sd= sculpt_data();
 	int val;
@@ -1745,7 +1747,8 @@ void sculptmode_draw_wires(int only_damaged, Mesh *me)
 	bglPolygonOffset(0.0);
 }
 
-void sculptmode_draw_mesh(int only_damaged) {
+void sculptmode_draw_mesh(int only_damaged) 
+{
 	Mesh *me= get_mesh(OBACT);
 	int i, j, dt, drawCurrentMat = 1, matnr= -1;
 
@@ -1799,7 +1802,7 @@ void sculptmode_draw_mesh(int only_damaged) {
 	glDisable(GL_DEPTH_TEST);
 }
 
-void sculptmode_correct_state()
+void sculptmode_correct_state(void)
 {
 	if(!sculpt_session())
 		sculpt_init_session();
@@ -1824,7 +1827,7 @@ char sculpt_modifiers_active(Object *ob)
 	return 0;
 }
 
-void sculpt()
+void sculpt(void)
 {
 	SculptData *sd= sculpt_data();
 	SculptSession *ss= sculpt_session();
@@ -2042,7 +2045,7 @@ void sculpt()
 	allqueue(REDRAWVIEW3D, 0);
 }
 
-void set_sculptmode()
+void set_sculptmode(void)
 {
 	if(G.f & G_SCULPTMODE) {
 		Mesh *me= get_mesh(OBACT);