[vala] Report error when using conflicting method modifiers in Genie parser

[Jamie McCracken <jamiemcc src gnome org>]

commit 41efbe449e61d9fd892449fa7735457d01646ffb
Author: Jamie McCracken <jamiemcc gnome org>
Date:   Mon Apr 13 17:57:03 2009 -0400

    Report error when using conflicting method modifiers  in Genie parser
---
 vala/valagenieparser.vala |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/vala/valagenieparser.vala b/vala/valagenieparser.vala
index cef9324..3bca600 100644
--- a/vala/valagenieparser.vala
+++ b/vala/valagenieparser.vala
@@ -2663,6 +2663,11 @@ public class Vala.Genie.Parser : CodeVisitor {
 		if (ModifierFlags.OVERRIDE in flags) {
 			method.overrides = true;
 		}
+		if ((method.is_abstract && method.is_virtual)
+		    || (method.is_abstract && method.overrides)
+		    || (method.is_virtual && method.overrides)) {
+			throw new ParseError.SYNTAX (get_error ("only one of `abstract', `virtual', or `override' may be specified"));
+		}
 		if (ModifierFlags.INLINE in flags) {
 			method.is_inline = true;
 		}