* unify various checks for whether a suspend function needs a
continuation;
* mark the continuation parameter with an origin (this also allows
correctly computing the offset of the local in codegen -- see the
new test);
* when wrapping `suspend fun main`, use a suspend reference instead of
a synthetic non-suspend lambda (required to correctly implement the
previous point, as previously the continuation parameter was passed
to main() itself correctly only because of very lenient checks in
AddContinuationLowering).
This commit is a hotfix rather then proper solution.
The source of the issue is that currently type variable fixation result
may change due to fixation order alteration for variables with the same priority.
For instance, having variables V1, V2, and proper types Type1, Type2, such that:
V1 <: Type1
V1 <: V2
Type2 <: V2
both variables will be fixed either to Type1, if V1 will be fixed first,
or to Type2 otherwise.
Since this limitation cannot be easily overcome, the taken approach is to remove
incedental constraint added after 2d5a0546 by restricting nullability constraint check
to `Nothing?` constraints only, thus postponing problematic variable fixation.
To clearify, additional constraint is correct and should cause no harm (in ideal world),
but currently its presence changes fixation order.
So without the restriction the previously used constraint from fixed outer variable
is no longer available by the time problematic variable type is being selected.
^KT-37043 Fixed
Use resulting descriptor extension receiver type instead of
ReceiverValue.type (which can contain captured types, which would be
approximated, and cause IR validation errors).
The number of initializations of the `value` field before the live range
begins does not really matter so long as we insert a write of a default
value to the local if there were none.
See KT-36812. Aside from the problem stated there, D8 will throw out the
entire LVT if it sees a variable that has not been written to (and will
generate incorrect SSA if the slot is reused with a different type).
Note: this only fixes a FIR test because it's missing an `else -> throw`
branch, and default initialization satisfies the verifier and masks the
incorrect control flow.
The reference type is approximated in Psi2Ir, so we may get Nothing as
a reference type argument. Better look at the arguments of the
referenced function.
It's not clear how one should rollback _all_ resolution results if
there is inapplicable call. Ideally, such calls should not be available
in coroutine block but for now, to have backward compatibility, we'll
just reanalyze coroutine block as a usual lambda if there is at least
one such call.
As a result, also remove diagnostic about non-applicable call as it
become useless with current reanalysis
#KT-37061 Fixed
#KT-32097 Fixed
#KT-32203 Fixed
#KT-35306 Fixed
#KT-36202 Fixed
#KT-36220 Fixed
#KT-32654 Fixed
Georgy Bronnikov