+/**
+ * Check for conflicting viewport_relative settings across shaders, and sets
+ * the value for the linked shader.
+ */
+static void
+link_layer_viewport_relative_qualifier(struct gl_shader_program *prog,
+ struct gl_program *gl_prog,
+ struct gl_shader **shader_list,
+ unsigned num_shaders)
+{
+ unsigned i;
+
+ /* Find first shader with explicit layer declaration */
+ for (i = 0; i < num_shaders; i++) {
+ if (shader_list[i]->redeclares_gl_layer) {
+ gl_prog->info.layer_viewport_relative =
+ shader_list[i]->layer_viewport_relative;
+ break;
+ }
+ }
+
+ /* Now make sure that each subsequent shader's explicit layer declaration
+ * matches the first one's.
+ */
+ for (; i < num_shaders; i++) {
+ if (shader_list[i]->redeclares_gl_layer &&
+ shader_list[i]->layer_viewport_relative !=
+ gl_prog->info.layer_viewport_relative) {
+ linker_error(prog, "all gl_Layer redeclarations must have identical "
+ "viewport_relative settings");
+ }
+ }
+}
+