[vala] Report error on unsupported type check expressions

[Jürg Billeter <juergbi src gnome org>]

commit 380b0786f633baa40b877f079317ab070b6402fb
Author: Jürg Billeter <j bitron ch>
Date:   Sun Aug 16 16:56:39 2009 +0200

    Report error on unsupported type check expressions
    
    Fixes bug 585344.

 ccode/Makefile.am                     |    1 +
 ccode/valaccodeinvalidexpression.vala |   33 +++++++++++++++++++++++++++++++++
 codegen/valaccodebasemodule.vala      |   15 ++++++++++++---
 3 files changed, 46 insertions(+), 3 deletions(-)
---
diff --git a/ccode/Makefile.am b/ccode/Makefile.am
index d70c568..af79c1f 100644
--- a/ccode/Makefile.am
+++ b/ccode/Makefile.am
@@ -42,6 +42,7 @@ libvalaccode_la_VALASOURCES = \
 	valaccodeifstatement.vala \
 	valaccodeincludedirective.vala \
 	valaccodeinitializerlist.vala \
+	valaccodeinvalidexpression.vala \
 	valaccodelabel.vala \
 	valaccodelinedirective.vala \
 	valaccodemacroreplacement.vala \
diff --git a/ccode/valaccodeinvalidexpression.vala b/ccode/valaccodeinvalidexpression.vala
new file mode 100644
index 0000000..cf01e31
--- /dev/null
+++ b/ccode/valaccodeinvalidexpression.vala
@@ -0,0 +1,33 @@
+/* valaccodeinvalidexpression.vala
+ *
+ * Copyright (C) 2009  Jürg Billeter
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
+ *
+ * Author:
+ * 	Jürg Billeter <j bitron ch>
+ */
+
+/**
+ * Represents an invalid expression.
+ */
+public class Vala.CCodeInvalidExpression : CCodeExpression {
+	public CCodeInvalidExpression () {
+	}
+
+	public override void write (CCodeWriter writer) {
+		assert_not_reached ();
+	}
+}
diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 0cfdb30..a970c3a 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -3656,16 +3656,18 @@ internal class Vala.CCodeBaseModule : CCodeModule {
 		expr.ccodenode = new CCodeBinaryExpression (op, cleft, cright);
 	}
 
-	public string get_type_check_function (TypeSymbol type) {
+	public string? get_type_check_function (TypeSymbol type) {
 		var cl = type as Class;
 		if (cl != null && cl.type_check_function != null) {
 			return cl.type_check_function;
+		} else if ((cl != null && cl.is_compact) || type is Struct || type is Enum || type is Delegate) {
+			return null;
 		} else {
 			return type.get_upper_case_cname ("IS_");
 		}
 	}
 
-	CCodeExpression create_type_check (CCodeNode ccodenode, DataType type) {
+	CCodeExpression? create_type_check (CCodeNode ccodenode, DataType type) {
 		var et = type as ErrorType;
 		if (et != null && et.error_code != null) {
 			var matches_call = new CCodeFunctionCall (new CCodeIdentifier ("g_error_matches"));
@@ -3678,7 +3680,11 @@ internal class Vala.CCodeBaseModule : CCodeModule {
 			var type_domain = new CCodeIdentifier (et.error_domain.get_upper_case_cname ());
 			return new CCodeBinaryExpression (CCodeBinaryOperator.EQUALITY, instance_domain, type_domain);
 		} else {
-			var ccheck = new CCodeFunctionCall (new CCodeIdentifier (get_type_check_function (type.data_type)));
+			string type_check_func = get_type_check_function (type.data_type);
+			if (type_check_func == null) {
+				return new CCodeInvalidExpression ();
+			}
+			var ccheck = new CCodeFunctionCall (new CCodeIdentifier (type_check_func));
 			ccheck.add_argument ((CCodeExpression) ccodenode);
 			return ccheck;
 		}
@@ -3688,6 +3694,9 @@ internal class Vala.CCodeBaseModule : CCodeModule {
 		generate_type_declaration (expr.type_reference, source_declarations);
 
 		expr.ccodenode = create_type_check (expr.expression.ccodenode, expr.type_reference);
+		if (expr.ccodenode is CCodeInvalidExpression) {
+			Report.error (expr.source_reference, "type check expressions not supported for compact classes, structs, and enums");
+		}
 	}
 
 	public override void visit_lambda_expression (LambdaExpression l) {