The fix is simple: Just don't have RenderTarget (which is literally named render TARGET) also be in charge of rendering things to itself.

meson.build

@@ -50,6 +50,10 @@ executable('rvo_test', [
   override_options: exe_defaults,
   dependencies: dependencies)
 
-executable('constness', 'sfml-const/constness.cpp',
+executable('sfml-constness', 'sfml-const/constness.cpp',
+  override_options: exe_defaults,
+  dependencies: dependencies)
+
+executable('sfml-fixed1', 'sfml-const/fixed.cpp',
   override_options: exe_defaults,
   dependencies: dependencies)

sfml-const/constness.cpp

@@ -7,14 +7,11 @@ void RenderTarget::draw(const Drawable& drawable) {
   drawable.draw(*this);
 }
 
-void Shape::draw(const RenderTarget& target) const {
+void Shape::draw(RenderTarget& target) const {
   cout << "shape draw\n";
 }
 
-using std::cout;
-
 int main() {
-
   RenderTarget target;
   Shape shape;
 

sfml-const/constness.hpp

@@ -9,10 +9,10 @@ class RenderTarget {
 
 class Drawable {
   public:
-    virtual void draw(const RenderTarget& target) const = 0;
+    virtual void draw(RenderTarget& target) const = 0;
 };
 
 class Shape : public Drawable {
   public:
-  void draw(const RenderTarget& target) const override;
+  void draw(RenderTarget& target) const override;
 };

sfml-const/fixed.cpp

@@ -0,0 +1,17 @@
+#include <iostream>
+#include "constness.hpp"
+
+using std::cout;
+
+void Shape::draw(RenderTarget& target) const {
+  cout << "shape draw\n";
+}
+
+int main() {
+  RenderTarget target;
+  Shape shape;
+
+  shape.draw(target);
+
+  return 0;
+}

sfml-const/fixed.hpp

@@ -0,0 +1,16 @@
+#pragma once
+
+class Drawable;
+
+class RenderTarget {
+};
+
+class Drawable {
+  public:
+    virtual void draw(RenderTarget& target) = 0;
+};
+
+class Shape : public Drawable {
+  public:
+  void draw(RenderTarget& target) const override;
+};