diff --git a/cif/CIFrdutils.c b/cif/CIFrdutils.c
index d1af7be5..f190a2ac 100644
--- a/cif/CIFrdutils.c
+++ b/cif/CIFrdutils.c
@@ -1469,9 +1469,9 @@ cifParseComment(void)
  * ----------------------------------------------------------------------------
  */
 
-Transform *
+const Transform *
 CIFDirectionToTrans(
-    Point *point)		/* Direction vector from origin. */
+    const Point *point)		/* Direction vector from origin. */
 {
     if ((point->p_x != 0) && (point->p_y == 0))
     {
diff --git a/cif/CIFread.h b/cif/CIFread.h
index 57f49e4a..c5400391 100644
--- a/cif/CIFread.h
+++ b/cif/CIFread.h
@@ -176,16 +176,14 @@ extern void CIFReadCellInit(int ptrkeys);
 extern void CIFReadCellCleanup(int filetype);
 extern LinkedRect *CIFPolyToRects(CIFPath *path, Plane *plane, PaintResultType *resultTbl,
                                   PaintUndoInfo *ui, bool isCalma);
-extern Transform *CIFDirectionToTrans(Point *point);
+extern const Transform *CIFDirectionToTrans(const Point *point);
 extern int CIFReadNameToType(char *name, bool newOK);
 
 extern int CIFCalmaLayerToCifLayer(int layer, int datatype, CIFReadStyle *calmaStyle);
-
 extern void CIFPropRecordPath(CellDef *def, CIFPath *pathheadp, bool iswire, char *propname);
 extern void CIFPaintWirePath(CIFPath *pathheadp, int width, bool endcap, Plane *plane,
                              PaintResultType *ptable, PaintUndoInfo *ui);
 extern void CIFMakeManhattanPath(CIFPath *pathHead, Plane *plane, PaintResultType *resultTbl, PaintUndoInfo *ui);
-
 extern int CIFEdgeDirection(CIFPath *first, CIFPath *last);
 
 /* Variable argument procedures require complete prototype */
diff --git a/commands/CmdCD.c b/commands/CmdCD.c
index 5d8f7d46..442a2542 100644
--- a/commands/CmdCD.c
+++ b/commands/CmdCD.c
@@ -4828,7 +4828,8 @@ cmdDumpParseArgs(
     CellDef *def, *rootDef, *editDef;
     bool hasChild, hasRoot, hasTrans;
     Rect rootBox, bbox;
-    Transform *tx_cell, trans_cell;
+    const Transform *tx_cell;
+    Transform trans_cell;
     char **av;
     char *cellnameptr, *fullpathname;
     int ac, clen;
diff --git a/lef/defRead.c b/lef/defRead.c
index c2753d1b..56effd90 100644
--- a/lef/defRead.c
+++ b/lef/defRead.c
@@ -1302,7 +1302,8 @@ DefReadLocation(use, f, oscale, tptr, noplace)
     Transform *tptr;
     bool noplace;
 {
-    Rect *r, tr, rect;
+    const Rect *r;
+    Rect tr, rect;
     int keyword;
     char *token;
     float x, y;
diff --git a/lef/lefRead.c b/lef/lefRead.c
index 22f526ea..b10934f3 100644
--- a/lef/lefRead.c
+++ b/lef/lefRead.c
@@ -722,7 +722,7 @@ LefReadLayers(f, obstruct, lreturn, rreturn)
     FILE *f;
     bool obstruct;
     TileType *lreturn;
-    Rect **rreturn;
+    const Rect **rreturn;
 {
     char *token;
     TileType curlayer = -1;
@@ -810,7 +810,7 @@ LefReadLayer(f, obstruct)
     FILE *f;
     bool obstruct;
 {
-    return LefReadLayers(f, obstruct, (TileType *)NULL, (Rect **)NULL);
+    return LefReadLayers(f, obstruct, (TileType *)NULL, (const Rect **)NULL);
 }
 
 /*
@@ -1200,7 +1200,8 @@ LefReadGeometry(lefMacro, f, oscale, do_list, is_imported)
     LinkedRect *newRect, *rectList;
     Point *pointList;
     int points;
-    Rect *paintrect, *contact = NULL;
+    Rect *paintrect;
+    const Rect *contact = NULL;
 
     static char *geometry_keys[] = {
 	"LAYER",
diff --git a/utils/geometry.c b/utils/geometry.c
index fff7c9c2..7d751e33 100644
--- a/utils/geometry.c
+++ b/utils/geometry.c
@@ -36,26 +36,26 @@ static char rcsid[] __attribute__ ((unused)) = "$Header: /usr/cvsroot/magic-8.0/
  *-------------------------------------------------------------------
  */
 
-global Transform GeoIdentityTransform	= {  1,  0,  0,  0,  1,  0 };
-global Transform GeoUpsideDownTransform	= {  1,  0,  0,  0, -1,  0 };
-global Transform GeoSidewaysTransform	= { -1,  0,  0,  0,  1,  0 };
-global Transform Geo90Transform		= {  0,  1,  0, -1,  0,  0 };
-global Transform Geo180Transform	= { -1,  0,  0,  0, -1,  0 };
-global Transform Geo270Transform	= {  0, -1,  0,  1,  0,  0 };
+global const Transform GeoIdentityTransform	= {  1,  0,  0,  0,  1,  0 };
+global const Transform GeoUpsideDownTransform	= {  1,  0,  0,  0, -1,  0 };
+global const Transform GeoSidewaysTransform	= { -1,  0,  0,  0,  1,  0 };
+global const Transform Geo90Transform		= {  0,  1,  0, -1,  0,  0 };
+global const Transform Geo180Transform	= { -1,  0,  0,  0, -1,  0 };
+global const Transform Geo270Transform	= {  0, -1,  0,  1,  0,  0 };
 
 /*
  * Additional Transforms (Reflections at 45 and 135 degrees)
  */
 
-global Transform GeoRef45Transform	= {  0,  1,  0,  1,  0,  0 };
-global Transform GeoRef135Transform	= {  0, -1,  0, -1,  0,  0 };
+global const Transform GeoRef45Transform	= {  0,  1,  0,  1,  0,  0 };
+global const Transform GeoRef135Transform	= {  0, -1,  0, -1,  0,  0 };
 
 /*
  *-------------------------------------------------------------------
  *	Declaration of the table of opposite directions:
  *-------------------------------------------------------------------
  */
-global int GeoOppositePos[] =
+global const int GeoOppositePos[] =
 {
 	GEO_CENTER,	/* GEO_CENTER */
 	GEO_SOUTH,	/* GEO_NORTH */
@@ -74,9 +74,9 @@ global int GeoOppositePos[] =
  *-------------------------------------------------------------------
  */
 
-global Rect  GeoNullRect = { {0, 0}, {0, 0} };
-global Rect  GeoInvertedRect = { {0, 0}, {-1, -1} };
-global Point GeoOrigin = { 0, 0 };
+global const Rect  GeoNullRect = { {0, 0}, {0, 0} };
+global const Rect  GeoInvertedRect = { {0, 0}, {-1, -1} };
+global const Point GeoOrigin = { 0, 0 };
 
 
 /*-------------------------------------------------------------------
diff --git a/utils/geometry.h b/utils/geometry.h
index 5ea15b55..fc82835e 100644
--- a/utils/geometry.h
+++ b/utils/geometry.h
@@ -211,19 +211,19 @@ extern void GeoScaleTrans(const Transform *trans1, int m, Transform *trans2);
  *-------------------------------------------------------------------
  */
 
-extern Transform GeoIdentityTransform;
-extern Transform GeoUpsideDownTransform;
-extern Transform GeoSidewaysTransform;
-extern Transform Geo90Transform;
-extern Transform Geo180Transform;
-extern Transform Geo270Transform;
-extern Transform GeoRef45Transform;
-extern Transform GeoRef135Transform;
+extern const Transform GeoIdentityTransform;
+extern const Transform GeoUpsideDownTransform;
+extern const Transform GeoSidewaysTransform;
+extern const Transform Geo90Transform;
+extern const Transform Geo180Transform;
+extern const Transform Geo270Transform;
+extern const Transform GeoRef45Transform;
+extern const Transform GeoRef135Transform;
 
-extern Rect GeoNullRect;
-extern Rect GeoInvertedRect;
-extern Point GeoOrigin;
+extern const Rect GeoNullRect;
+extern const Rect GeoInvertedRect;
+extern const Point GeoOrigin;
 
-extern int GeoOppositePos[];
+extern const int GeoOppositePos[];
 
 #endif /* _GEOMETRY_H */