diff --git a/direct/src/directbase/ppython.cxx b/direct/src/directbase/ppython.cxx
index 4d673d96b6..65f1272c8a 100644
--- a/direct/src/directbase/ppython.cxx
+++ b/direct/src/directbase/ppython.cxx
@@ -36,7 +36,7 @@ int main(int argc, char *mb_argv[]) {
     size_t len = mbstowcs(NULL, mb_argv[i], 0);
     argv[i] = new wchar_t[len + 1];
     mbstowcs(argv[i], mb_argv[i], len);
-    argv[i][len] = NULL;
+    argv[i][len] = 0;
   }
   // Just for good measure
   argv[argc] = NULL;
diff --git a/panda/src/gobj/geomPrimitive.cxx b/panda/src/gobj/geomPrimitive.cxx
index 80408a18c5..797ea9e1c8 100644
--- a/panda/src/gobj/geomPrimitive.cxx
+++ b/panda/src/gobj/geomPrimitive.cxx
@@ -1398,9 +1398,9 @@ modify_ends() {
 //               you do, be sure you know what you are doing!
 ////////////////////////////////////////////////////////////////////
 void GeomPrimitive::
-set_ends(CPTA_int ends) {
+set_ends(PTA_int ends) {
   CDWriter cdata(_cycler, true);
-  cdata->_ends = (PTA_int &)ends;
+  cdata->_ends = ends;
 
   cdata->_modified = Geom::get_next_modified();
   cdata->_got_minmax = false;
diff --git a/panda/src/gobj/geomPrimitive.h b/panda/src/gobj/geomPrimitive.h
index da787edad7..d2a2f4cbd1 100644
--- a/panda/src/gobj/geomPrimitive.h
+++ b/panda/src/gobj/geomPrimitive.h
@@ -169,7 +169,7 @@ PUBLISHED:
 
   INLINE CPTA_int get_ends() const;
   PTA_int modify_ends();
-  void set_ends(CPTA_int ends);
+  void set_ends(PTA_int ends);
 
   INLINE CPT(GeomVertexArrayData) get_mins() const;
   INLINE CPT(GeomVertexArrayData) get_maxs() const;
diff --git a/panda/src/gobj/shader.I b/panda/src/gobj/shader.I
index eccb05d79f..0dae6344dd 100644
--- a/panda/src/gobj/shader.I
+++ b/panda/src/gobj/shader.I
@@ -20,7 +20,7 @@
 //               type.
 ////////////////////////////////////////////////////////////////////
 INLINE Filename Shader::
-get_filename(const ShaderType &type) const {
+get_filename(ShaderType type) const {
   if (_filename._separate && type != ST_none) {
     switch (type) {
       case ST_vertex:
@@ -59,7 +59,7 @@ get_filename(const ShaderType &type) const {
 //  Description: Return the Shader's text for the given shader type.
 ////////////////////////////////////////////////////////////////////
 INLINE const string &Shader::
-get_text(const ShaderType &type) const {
+get_text(ShaderType type) const {
   if (_text._separate) {
     nassertr(type != ST_none || !_text._shared.empty(), _text._shared);
     switch (type) {
diff --git a/panda/src/gobj/shader.h b/panda/src/gobj/shader.h
index 0c2fb79401..c0c31afaae 100644
--- a/panda/src/gobj/shader.h
+++ b/panda/src/gobj/shader.h
@@ -97,8 +97,8 @@ PUBLISHED:
                          const string &tess_evaluation = "");
   static PT(Shader) make_compute(ShaderLanguage lang, const string &body);
 
-  INLINE Filename get_filename(const ShaderType &type = ST_none) const;
-  INLINE const string &get_text(const ShaderType &type = ST_none) const;
+  INLINE Filename get_filename(ShaderType type = ST_none) const;
+  INLINE const string &get_text(ShaderType type = ST_none) const;
   INLINE bool get_error_flag() const;
   INLINE ShaderLanguage get_language() const;