fix invalid error reporting

hxsl/Checker.hx

@@ -571,7 +571,7 @@ class Checker {
 			}
 			loop(e);
 			var sexpr = null;
-			try sexpr = loadShader(path.join(".")) catch( err : Dynamic ) error(Std.string(err), e.pos);
+			try sexpr = loadShader(path.join(".")) catch( err : Error ) error(Std.string(err), e.pos);
 			if( sexpr != null )
 				checkExpr(sexpr, funs, isImport, true);
 		default: