On Tue, 5 Nov 2024 19:51:04 GMT, Vicente Romero <vrom...@openjdk.org> wrote:
> Javac is not issuing a mandated unchecked cast warning for code like:
>
>
> import java.lang.invoke.VarHandle;
>
> class VarHandleCast<V> {
> VarHandle vh;
> V method(Object obj) {
> return (V)vh.getAndSet(this, obj);
> }
> }
>
>
> according to the spec the return type inferred for this method polymorphic
> method should be Object see:
>
> - If the compile-time declaration for the method invocation is a signature
> polymorphic method, then:
> ...
> – The compile-time result is determined as follows:
> Otherwise, if the method invocation expression is the operand of a
> cast
> expression (§15.16), the compile-time result is the erasure of the type
> of the
> cast expression (§4.6).
>
> javac is not doing the type erasure mandated by the spec which is what this
> PR is fixing
>
> TIA
>
> Note: I had to add some annotations to suppress warnings in java.base that
> were not being issued before due to the javac bug
This pull request has now been integrated.
Changeset: cc2acd14
Author: Vicente Romero <vrom...@openjdk.org>
URL:
https://git.openjdk.org/jdk/commit/cc2acd14b13ada243fc13dc4d9007c4e2df56148
Stats: 40 lines in 10 files changed: 38 ins; 0 del; 2 mod
8343286: Missing unchecked cast warning in polymorphic method call
Reviewed-by: mcimadamore
-------------
PR: https://git.openjdk.org/jdk/pull/21914
