diff --git a/samples/drawing/mondrian.xpm b/samples/drawing/mondrian.xpm
index 409f27a843..7b2188656f 100644
--- a/samples/drawing/mondrian.xpm
+++ b/samples/drawing/mondrian.xpm
@@ -1,5 +1,5 @@
 /* XPM */
-static char *mondrian_xpm[] = {
+static const char *mondrian_xpm[] = {
 /* columns rows colors chars-per-pixel */
 "32 32 6 1",
 "  c Black",
diff --git a/samples/drawing/smile.xpm b/samples/drawing/smile.xpm
index 156d24eb0e..506dfeca27 100644
--- a/samples/drawing/smile.xpm
+++ b/samples/drawing/smile.xpm
@@ -1,5 +1,5 @@
 /* XPM */
-static char *smile_xpm[] = {
+static const char *smile_xpm[] = {
 /* columns rows colors chars-per-pixel */
 "32 32 4 1",
 ". c Black",