Index: graphviz-2.6/lib/agraph/edge.c
===================================================================
--- graphviz-2.6.orig/lib/agraph/edge.c
+++ graphviz-2.6/lib/agraph/edge.c
@@ -153,25 +153,29 @@ static Agedge_t *agfindedge_by_id(Agnode
 
 void agedgesetop(Agraph_t * g, Agedge_t * e, int ins)
 {
-    Dtlink_t **seq_set, **id_set;
+    union {
+	Dtlink_t **dtlink;
+	Agedge_t **agedge;
+    } seq_set;
+    Dtlink_t **id_set;
     Agnode_t *n;		/* node where <e> is referenced */
 
     if (AGTYPE(e) == AGOUTEDGE) {
 	n = AGOUT2IN(e)->node;
-	seq_set = (Dtlink_t **) & (n->out);
+	seq_set.agedge = & (n->out);
 	id_set = &(n->outid);
     } else {
 	n = AGIN2OUT(e)->node;
-	seq_set = (Dtlink_t **) & (n->in);
+	seq_set.agedge = & (n->in);
 	id_set = &(n->inid);
     }
 
-    dtrestore(g->e_seq, *seq_set);
+    dtrestore(g->e_seq, *seq_set.dtlink);
     if (ins)
 	dtinsert(g->e_seq, e);
     else
 	dtdelete(g->e_seq, e);
-    *seq_set = dtextract(g->e_seq);
+    *seq_set.dtlink = dtextract(g->e_seq);
 
     dtrestore(g->e_id, *id_set);
     if (ins)
Index: graphviz-2.6/lib/agraph/flatten.c
===================================================================
--- graphviz-2.6.orig/lib/agraph/flatten.c
+++ graphviz-2.6/lib/agraph/flatten.c
@@ -30,8 +30,14 @@ void agflatten_elist(Dict_t * d, Dtlink_
 
 void agflatten_edges(Agraph_t * g, Agnode_t * n)
 {
-    agflatten_elist(g->e_seq, (Dtlink_t **) & (n->out));
-    agflatten_elist(g->e_seq, (Dtlink_t **) & (n->in));
+    union {
+	Dtlink_t **dtlink;
+	Agedge_t **agedge;
+    } out, in;
+    out.agedge = & (n->out);
+    in.agedge = & (n->in);
+    agflatten_elist(g->e_seq, out.dtlink);
+    agflatten_elist(g->e_seq, in.dtlink);
 }
 
 void agflatten(Agraph_t * g, int flag)
Index: graphviz-2.6/lib/gd/fontwheeltest.c
===================================================================
--- graphviz-2.6.orig/lib/gd/fontwheeltest.c
+++ graphviz-2.6/lib/gd/fontwheeltest.c
@@ -21,7 +21,10 @@ void
 dowheel (gdImagePtr im, int color, char *fontfile, int fontsize,
 	double angle, int x, int y, int offset, char *string)
 {
-  int brect[8];
+  union {
+    int coords[8];
+    gdPoint points[4];
+  } brect;
   FILE *err;
   double curangrads, curang, x0, y0;
   char *cp;
@@ -40,16 +43,16 @@ dowheel (gdImagePtr im, int color, char 
 
       /* The case of newlines is taken care of in the gdImageStringTTF call */
 #if defined(OLDER_GD)
-      cp = gdImageStringTTF (im, brect, color, fontfile, fontsize,
+      cp = gdImageStringTTF (im, brect.coords, color, fontfile, fontsize,
 			  curangrads, x0, y0, string);
 #else
-      cp = gdImageStringFT (im, brect, color, fontfile, fontsize,
+      cp = gdImageStringFT (im, brect.coords, color, fontfile, fontsize,
 			 curangrads, x0, y0, string);
 #endif
       if (cp)
 	doerr (err, cp);
 
-      gdImagePolygon (im, (gdPointPtr)brect, 4, color);
+      gdImagePolygon (im, brect.points, 4, color);
     }
 
   fclose (err);
Index: graphviz-2.6/tclpkg/tcldot/tcldot.c
===================================================================
--- graphviz-2.6.orig/tclpkg/tcldot/tcldot.c
+++ graphviz-2.6/tclpkg/tcldot/tcldot.c
@@ -1232,6 +1232,8 @@ static int graphcmd(ClientData clientDat
 	return TCL_OK;
 
     } else if ((c == 'w') && (strncmp(argv[1], "write", length) == 0)) {
+	void *aliasing_dummy;
+
 	g = g->root;
 	if (argc < 3) {
 	    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
@@ -1258,9 +1260,11 @@ static int graphcmd(ClientData clientDat
 	gvc->job->output_lang =
             gvrender_select(gvc->job, gvc->job->output_langname);
 
+	aliasing_dummy = gvc->job->output_file;
 	if (Tcl_GetOpenFile (interp, argv[2], 1, 1,
-	     (ClientData *) &(gvc->job->output_file)) != TCL_OK)
+	     (ClientData *) &aliasing_dummy) != TCL_OK)
 	    return TCL_ERROR;
+	gvc->job->output_file = aliasing_dummy;
 
 	/* make sure that layout is done  - unless canonical output */
 	if ((!GD_drawing(g) || argc > 4)