glsl: Expose a public glsl_type::void_type const pointer.

This is analogous to glsl_type::int_type and all the others.

src/glsl/builtin_types.h

@@ -24,10 +24,11 @@
 const glsl_type glsl_type::_error_type =
    glsl_type(GL_INVALID_ENUM, GLSL_TYPE_ERROR, 0, 0, "");
 
-const glsl_type glsl_type::void_type =
+const glsl_type glsl_type::_void_type =
    glsl_type(GL_INVALID_ENUM, GLSL_TYPE_VOID, 0, 0, "void");
 
 const glsl_type *const glsl_type::error_type = & glsl_type::_error_type;
+const glsl_type *const glsl_type::void_type = & glsl_type::_void_type;
 
 /** \name Core built-in types
  *

src/glsl/glsl_types.cpp

@@ -120,7 +120,7 @@ glsl_type::generate_100ES_types(glsl_symbol_table *symtab)
    add_types_to_symbol_table(symtab, builtin_structure_types,
 			     Elements(builtin_structure_types),
 			     false);
-   add_types_to_symbol_table(symtab, &void_type, 1, false);
+   add_types_to_symbol_table(symtab, void_type, 1, false);
 }
 
 void
@@ -279,7 +279,7 @@ const glsl_type *
 glsl_type::get_instance(unsigned base_type, unsigned rows, unsigned columns)
 {
    if (base_type == GLSL_TYPE_VOID)
-      return &void_type;
+      return void_type;
 
    if ((rows < 1) || (rows > 4) || (columns < 1) || (columns > 4))
       return error_type;

src/glsl/glsl_types.h

@@ -142,6 +142,7 @@ struct glsl_type {
     */
    /*@{*/
    static const glsl_type *const error_type;
+   static const glsl_type *const void_type;
    static const glsl_type *const int_type;
    static const glsl_type *const ivec4_type;
    static const glsl_type *const uint_type;
@@ -424,7 +425,7 @@ private:
     */
    /*@{*/
    static const glsl_type _error_type;
-   static const glsl_type void_type;
+   static const glsl_type _void_type;
    static const glsl_type builtin_core_types[];
    static const glsl_type builtin_structure_types[];
    static const glsl_type builtin_110_deprecated_structure_types[];