diff --git a/panda/src/framework/rock_floor_src.cxx b/panda/src/framework/rock_floor_src.cxx
index 69776f49fa..37a7dd73c0 100644
--- a/panda/src/framework/rock_floor_src.cxx
+++ b/panda/src/framework/rock_floor_src.cxx
@@ -5,7 +5,7 @@
  * bin2c -n rock_floor -static -string -o rock_floor_src.cxx /home/drose/fit/egg/rock-floor.rgb
  */
 
-static const char rock_floor[] = {
+static const unsigned char rock_floor[] = {
   0x01, 0xda, 0x01, 0x01, 0x00, 0x03, 0x01, 0x00, 0x01, 0x00, 0x00,
   0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x00, 0x00,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
diff --git a/panda/src/framework/windowFramework.cxx b/panda/src/framework/windowFramework.cxx
index 3c35b2d489..2c96fa1e0f 100644
--- a/panda/src/framework/windowFramework.cxx
+++ b/panda/src/framework/windowFramework.cxx
@@ -642,7 +642,7 @@ load_default_model(const NodePath &parent) {
 
   // Get the default texture to apply to the triangle; it's compiled
   // into the code these days.
-  string rock_floor_string(rock_floor, rock_floor_len);
+  string rock_floor_string((const char *)rock_floor, rock_floor_len);
   istringstream rock_floor_strm(rock_floor_string);
   PNMImage rock_floor_pnm;
   if (rock_floor_pnm.read(rock_floor_strm, "rock-floor.rgb")) {