tailrec f(x: () -> T = { y }, y: T = ...) = f()
-- at the call we know that in `x` the observed value of `y` is `null`,
but the constructor should still have a single parameter.
This is needed so that SharedVariablesLowering doesn't get confused, and
SharedVariablesLowering should run after TailrecLowering to properly
optimize tailrec calls in inline lambdas.
Using `kotlin.jvm.functions.Function{n+1}` (via
`getJvmSuspendFunctionClass`) for suspend functions was wrong in the
function reference lowering, because we didn't adapt the parameter types
by transforming the last type to Continuation and adding Object, and
generic signature ended up being incorrect.
Actually there was no need to use `kotlin.jvm.functions.Function{n+1}`
at all. We can just use the built-in
`kotlin.coroutines.SuspendFunction{n}` as a supertype, and it will be
mapped correctly later in codegen. It's not even needed to add the
`kotlin.coroutines.jvm.internal.SuspendFunction` marker manually, since
it's also handled by the codegen (see `IrTypeMapper.mapClassSignature`).
#KT-48732 Fixed
The constraint depends on a resolution candidate, because it can be Java static or companion object's member (don't need add constraint in this case)
^KT-41978 Fixed
`mappedVarargElements` are populated with parameters from
`argumentMapping`, which is computed using `ArgumentsToParametersMapper`
which calls `original` on all value parameters (see
ArgumentsToParametersMapper.kt:136).
So the code that adds empty lists for unassigned vararg parameters
should also call `original`. Otherwise, in the added test, we ended up
with two arguments for the parameter `s` in `id(::base1)`, one for
`Base.s` containing the correct value, and another for `Derived.s`
containing the empty list. Psi2ir took the last one, which resulted in
empty array being passed to the vararg parameter.
Note that all of this is caused by the fact that `original` of a fake
override parameter is the parameter of the base function. This seems
suspicious because `original` of a fake override _function_ is that fake
override itself (NOT the base function), but this would probably be very
risky to change at this point.
#KT-48835 Fixed
Parameter of a synthetic SAM adapter always has a function type (not a
subtype). Checking for the subtypes broke the case from KT-46908, where
fun interface is itself a subtype of a function type.
#KT-46908 Fixed
In case the cast value is used as a receiver to a private method call,
the cast is actually necessary, see KT-48927. Also, this optimization
has backfired once already (see kt48659_identityEqualsWithCastToAny.kt).
It seems that the best way to optimize these casts is not to generate
them in the first place, and/or use bytecode postprocessing.
Apparently the only kind of casts which need to be eliminated are those
which occur on an inline class to its supertype. Otherwise the
unsafe-coerce intrinsic is inserted at the incorrect place, and several
tests fail (uncastInlineClassToAnyAndBack.kt, genericOverride.kt,
classGenericOverride.kt).
#KT-48927 Fixed