Add missing destructor

Author: solidpixel

hwcpipe/include/hwcpipe/detail/internal_types.hpp

@@ -29,6 +29,11 @@ namespace expression {
  */
 class context {
   public:
+    /**
+     * @brief Ensure we have a destructor for polymorphic type.
+     */
+    virtual ~context() {}
+
     /**
      * @brief Returns the value a hardware counter from the sampler to be used
      * in the expression evaluator