3 files changed, 3 insertions, 0 deletions
diff --git a/src/glsl/ast.h b/src/glsl/ast.h
index a77b522705..1420f234b6 100644
--- a/src/glsl/ast.h
+++ b/src/glsl/ast.h
@@ -129,6 +129,7 @@ protected:
     * be created.
     */
    ast_node(void);
+   virtual ~ast_node() {}
 };
 
 
diff --git a/src/glsl/ir.h b/src/glsl/ir.h
index 102a68b655..f3c1d42108 100644
--- a/src/glsl/ir.h
+++ b/src/glsl/ir.h
@@ -131,6 +131,7 @@ protected:
       ir_type = ir_type_unset;
       type = NULL;
    }
+   virtual ~ir_instruction() {}
 };
 
 
diff --git a/src/glsl/ir_hierarchical_visitor.h b/src/glsl/ir_hierarchical_visitor.h
index dc177f5eb0..387563f113 100644
--- a/src/glsl/ir_hierarchical_visitor.h
+++ b/src/glsl/ir_hierarchical_visitor.h
@@ -77,6 +77,7 @@ enum ir_visitor_status {
 class ir_hierarchical_visitor {
 public:
    ir_hierarchical_visitor();
+   virtual ~ir_hierarchical_visitor() {}
 
    /**
     * \name Visit methods for leaf-node classes