diff --git a/opm/core/grid.c b/opm/core/grid.c
index 8f8746af..60093e83 100644
--- a/opm/core/grid.c
+++ b/opm/core/grid.c
@@ -26,21 +26,21 @@ destroy_grid(struct UnstructuredGrid *g)
 {
     if (g!=NULL)
     {
-	free(g->face_nodes);
-	free(g->face_nodepos);
-	free(g->face_cells);
-	free(g->cell_facepos);
-	free(g->cell_faces);
+        free(g->face_nodes);
+        free(g->face_nodepos);
+        free(g->face_cells);
+        free(g->cell_facepos);
+        free(g->cell_faces);
 
-	free(g->node_coordinates);
-	free(g->face_centroids);
-	free(g->face_areas);
-	free(g->face_normals);
-	free(g->cell_centroids);
-	free(g->cell_volumes);
+        free(g->node_coordinates);
+        free(g->face_centroids);
+        free(g->face_areas);
+        free(g->face_normals);
+        free(g->cell_centroids);
+        free(g->cell_volumes);
 
-	free(g->global_cell);
-	free(g->cell_facetag);
+        free(g->global_cell);
+        free(g->cell_facetag);
     }
 
     free(g);
@@ -55,7 +55,7 @@ create_grid_empty(void)
     G = malloc(1 * sizeof *G);
 
     if (G != NULL) {
-	*G = g;
+        *G = g;
     }
 
     return G;
@@ -64,11 +64,11 @@ create_grid_empty(void)
 
 struct UnstructuredGrid *
 allocate_grid(size_t ndims     ,
-	      size_t ncells    ,
-	      size_t nfaces    ,
-	      size_t nfacenodes,
-	      size_t ncellfaces,
-	      size_t nnodes    )
+              size_t ncells    ,
+              size_t nfaces    ,
+              size_t nfacenodes,
+              size_t ncellfaces,
+              size_t nnodes    )
 {
     size_t nel;
     struct UnstructuredGrid *G;
@@ -76,58 +76,58 @@ allocate_grid(size_t ndims     ,
     G = create_grid_empty();
 
     if (G != NULL) {
-	/* Node fields ---------------------------------------- */
-	nel                 = nnodes * ndims;
-	G->node_coordinates = malloc(nel * sizeof *G->node_coordinates);
+        /* Node fields ---------------------------------------- */
+        nel                 = nnodes * ndims;
+        G->node_coordinates = malloc(nel * sizeof *G->node_coordinates);
 
-	/* Face fields ---------------------------------------- */
-	nel               = nfacenodes;
-	G->face_nodes     = malloc(nel * sizeof *G->face_nodes);
+        /* Face fields ---------------------------------------- */
+        nel               = nfacenodes;
+        G->face_nodes     = malloc(nel * sizeof *G->face_nodes);
 
-	nel               = nfaces + 1;
-	G->face_nodepos   = malloc(nel * sizeof *G->face_nodepos);
+        nel               = nfaces + 1;
+        G->face_nodepos   = malloc(nel * sizeof *G->face_nodepos);
 
-	nel               = 2 * nfaces;
-	G->face_cells     = malloc(nel * sizeof *G->face_cells);
+        nel               = 2 * nfaces;
+        G->face_cells     = malloc(nel * sizeof *G->face_cells);
 
-	nel               = nfaces * ndims;
-	G->face_centroids = malloc(nel * sizeof *G->face_centroids);
+        nel               = nfaces * ndims;
+        G->face_centroids = malloc(nel * sizeof *G->face_centroids);
 
-	nel               = nfaces * ndims;
-	G->face_normals   = malloc(nel * sizeof *G->face_normals);
+        nel               = nfaces * ndims;
+        G->face_normals   = malloc(nel * sizeof *G->face_normals);
 
-	nel               = nfaces * 1;
-	G->face_areas     = malloc(nel * sizeof *G->face_areas);
+        nel               = nfaces * 1;
+        G->face_areas     = malloc(nel * sizeof *G->face_areas);
 
 
-	/* Cell fields ---------------------------------------- */
-	nel               = ncellfaces;
-	G->cell_faces     = malloc(nel * sizeof *G->cell_faces);
+        /* Cell fields ---------------------------------------- */
+        nel               = ncellfaces;
+        G->cell_faces     = malloc(nel * sizeof *G->cell_faces);
 
-	nel               = ncells + 1;
-	G->cell_facepos   = malloc(nel * sizeof *G->cell_facepos);
+        nel               = ncells + 1;
+        G->cell_facepos   = malloc(nel * sizeof *G->cell_facepos);
 
-	nel               = ncells * ndims;
-	G->cell_centroids = malloc(nel * sizeof *G->cell_centroids);
+        nel               = ncells * ndims;
+        G->cell_centroids = malloc(nel * sizeof *G->cell_centroids);
 
-	nel               = ncells * 1;
-	G->cell_volumes   = malloc(nel * sizeof *G->cell_volumes);
+        nel               = ncells * 1;
+        G->cell_volumes   = malloc(nel * sizeof *G->cell_volumes);
 
-	if ((G->node_coordinates == NULL) ||
-	    (G->face_nodes       == NULL) ||
-	    (G->face_nodepos     == NULL) ||
-	    (G->face_cells       == NULL) ||
-	    (G->face_centroids   == NULL) ||
-	    (G->face_normals     == NULL) ||
-	    (G->face_areas       == NULL) ||
-	    (G->cell_faces       == NULL) ||
-	    (G->cell_facepos     == NULL) ||
-	    (G->cell_centroids   == NULL) ||
-	    (G->cell_volumes     == NULL)  )
-	    {
-		destroy_grid(G);
-		G = NULL;
-	    }
+        if ((G->node_coordinates == NULL) ||
+            (G->face_nodes       == NULL) ||
+            (G->face_nodepos     == NULL) ||
+            (G->face_cells       == NULL) ||
+            (G->face_centroids   == NULL) ||
+            (G->face_normals     == NULL) ||
+            (G->face_areas       == NULL) ||
+            (G->cell_faces       == NULL) ||
+            (G->cell_facepos     == NULL) ||
+            (G->cell_centroids   == NULL) ||
+            (G->cell_volumes     == NULL)  )
+            {
+                destroy_grid(G);
+                G = NULL;
+            }
     }
 
     return G;