vala: Warn when directly accessing member of silent cast-expression

"foo as TypeSymbol" may result in `null' and accessing it without check is
not recommended. If the invocation context provides information that `null'
is not a possible result then use an unsafe cast "(TypeSymbol) foo".

diff --git a/vala/valamemberaccess.vala b/vala/valamemberaccess.vala
index 37eeafb875f27e53245009050a664df5cd2f91f8..ad3f3d0fc9e3d6a8a342feae409ba77887620dbf 100644 (file)
--- a/vala/valamemberaccess.vala
+++ b/vala/valamemberaccess.vala
@@ -343,6 +343,10 @@ public class Vala.MemberAccess : Expression {
                                }
                        }
 
+                       if (inner is CastExpression && ((CastExpression) inner).is_silent_cast) {
+                               Report.warning (source_reference, "Access to possible `null'. Perform a check or use an unsafe cast.");
+                       }
+
                        if (inner is MemberAccess || inner is BaseAccess) {
                                base_symbol = inner.symbol_reference;