Cleanup: use listbase clear

source/blender/blenkernel/intern/curve.c

@@ -2546,7 +2546,8 @@ void BKE_curve_bevelList_free(ListBase *bev)
 		}
 		MEM_freeN(bl);
 	}
-	bev->first = bev->last = NULL;
+
+	BLI_listbase_clear(bev);
 }
 
 void BKE_curve_bevelList_make(Object *ob, ListBase *nurbs, bool for_render)

source/blender/blenloader/intern/readfile.c

@@ -3449,7 +3449,7 @@ static void direct_link_image(FileData *fd, Image *ima)
 		ima->packedfile = direct_link_packedfile(fd, ima->packedfile);
 	}
 
-	ima->anims.first = ima->anims.last = NULL;
+	BLI_listbase_clear(&ima->anims);
 	ima->preview = direct_link_preview_image(fd, ima->preview);
 	ima->stereo3d_format = newdataadr(fd, ima->stereo3d_format);
 	ima->ok = 1;
@@ -5408,7 +5408,7 @@ static void lib_link_scene(FileData *fd, Main *main)
 						seq->scene_sound = BKE_sound_add_scene_sound_defaults(sce, seq);
 					}
 				}
-				seq->anims.first = seq->anims.last = NULL;
+				BLI_listbase_clear(&seq->anims);
 
 				lib_link_sequence_modifiers(fd, sce, &seq->modifiers);
 			}

source/blender/editors/gpencil/gpencil_edit.c

@@ -247,7 +247,7 @@ void ED_gpencil_strokes_copybuf_free(void)
 		BLI_freelinkN(&gp_strokes_copypastebuf, gps);
 	}
 	
-	gp_strokes_copypastebuf.first = gp_strokes_copypastebuf.last = NULL;
+	BLI_listbase_clear(&gp_strokes_copypastebuf);
 }
 
 /* --------------------- */

source/blender/makesrna/intern/rna_define.c

@@ -533,7 +533,7 @@ BlenderRNA *RNA_create(void)
 	brna = MEM_callocN(sizeof(BlenderRNA), "BlenderRNA");
 
 	DefRNA.sdna = DNA_sdna_from_data(DNAstr,  DNAlen, false);
-	DefRNA.structs.first = DefRNA.structs.last = NULL;
+	BLI_listbase_clear(&DefRNA.structs);
 	DefRNA.error = 0;
 	DefRNA.preprocess = 1;
 
@@ -720,8 +720,8 @@ StructRNA *RNA_def_struct_ptr(BlenderRNA *brna, const char *identifier, StructRN
 		 * use MEM_dupallocN, data structs may not be alloced but builtin */
 		memcpy(srna, srnafrom, sizeof(StructRNA));
 		srna->cont.prophash = NULL;
-		srna->cont.properties.first = srna->cont.properties.last = NULL;
-		srna->functions.first = srna->functions.last = NULL;
+		BLI_listbase_clear(&srna->cont.properties);
+		BLI_listbase_clear(&srna->functions);
 		srna->py_type = NULL;
 
 		if (DefRNA.preprocess) {

source/blender/render/intern/source/pipeline.c

@@ -2205,7 +2205,7 @@ static void free_all_freestyle_renders(void)
 			/* detach the window manager from freestyle bmain (see comments
 			 * in add_freestyle() for more detail)
 			 */
-			re1->freestyle_bmain->wm.first = re1->freestyle_bmain->wm.last = NULL;
+			BLI_listbase_clear(&re1->freestyle_bmain->wm);
 
 			BKE_main_free(re1->freestyle_bmain);
 			re1->freestyle_bmain = NULL;