diff --git a/compiler/res/prog8lib/cx16lib.p8 b/compiler/res/prog8lib/cx16lib.p8
index 5538bac5a..288ab0e45 100644
--- a/compiler/res/prog8lib/cx16lib.p8
+++ b/compiler/res/prog8lib/cx16lib.p8
@@ -192,11 +192,12 @@ romsub $ff4d = clock_set_date_time() clobbers(A, X, Y)      ; args: r0, r1, r2,
 romsub $ff50 = clock_get_date_time() clobbers(A)            ; outout args: r0, r1, r2, r3L
 
 ; high level graphics & fonts
-romsub $ff20 = GRAPH_init()             ; uses vectors=r0
-romsub $ff23 = GRAPH_clear()
+; TODO specify the correct clobbers for GRAPH and FB functions
+romsub $ff20 = GRAPH_init()  clobbers(A,X,Y)           ; uses vectors=r0
+romsub $ff23 = GRAPH_clear()  clobbers(A,X,Y)
 romsub $ff26 = GRAPH_set_window()       ; uses x=r0, y=r1, width=r2, height=r3
-romsub $ff29 = GRAPH_set_colors(ubyte stroke @A, ubyte fill @X, ubyte background @Y)
-romsub $ff2c = GRAPH_draw_line()        ; uses x1=r0, y1=r1, x2=r2, y2=r3
+romsub $ff29 = GRAPH_set_colors(ubyte stroke @A, ubyte fill @X, ubyte background @Y) clobbers (A,X,Y)
+romsub $ff2c = GRAPH_draw_line()  clobbers(A,X,Y)       ; uses x1=r0, y1=r1, x2=r2, y2=r3
 romsub $ff2f = GRAPH_draw_rect(ubyte fill @Pc)        ; uses x=r0, y=r1, width=r2, height=r3, cornerradius=r4
 romsub $ff32 = GRAPH_move_rect()        ; uses sx=r0, sy=r1, tx=r2, ty=r3, width=r4, height=r5
 romsub $ff35 = GRAPH_draw_oval(ubyte fill @Pc)        ; uses x=r0, y=r1, width=r2, height=r3
diff --git a/examples/cx16/cube3d-gfx.p8 b/examples/cx16/cube3d-gfx.p8
index 3b2a934da..aa0890154 100644
--- a/examples/cx16/cube3d-gfx.p8
+++ b/examples/cx16/cube3d-gfx.p8
@@ -31,9 +31,9 @@ main {
             rotate_vertices(msb(anglex), msb(angley), msb(anglez))
             cx16.GRAPH_clear()
             draw_lines()
-            anglex-=250
-            angley+=109
-            anglez+=226
+            anglex-=500
+            angley+=217
+            anglez+=452
         }
     }
 
@@ -84,7 +84,7 @@ main {
             cx16.r1 = rotatedy[vFrom] / persp1 + screen_height/2 as uword
             cx16.r2 = rotatedx[vTo] / persp2 + screen_width/2 as uword
             cx16.r3 = rotatedy[vTo] / persp2 + screen_height/2 as uword
-            cx16.GRAPH_draw_line()      ; TODO are there bugs in here?  the lines are all wrong...
+            cx16.GRAPH_draw_line()
         }
     }
 }
diff --git a/examples/test.p8 b/examples/test.p8
index f90540f22..7f53bfdfc 100644
--- a/examples/test.p8
+++ b/examples/test.p8
@@ -11,6 +11,8 @@ main {
 
         c64.CHROUT('*')
 
+        uword value = lsb(rnd() & 31)   ; TODO fix compiler crash
+
 
 ;asmsub  clear_screen (ubyte char @ A, ubyte color @ Y) clobbers(A)  { ...}
 ; TODO dont cause name conflict if we define sub or sub with param 'color' or even a var 'color' later.