This commit adds availability checking for properties to Sema. When
EnableExperimentalAvailabilityChecking is enabled, we now emit a diagnostic
when a potentially unavailable property is accessed. To support this, we
now build type refinement contexts for most ValueDecls.
Swift SVN r22622
This patch adds diagnostics for initializers that are potentially unavailable.
It does not treat such initializers as optionals, even when
EnableExperimentalUnavailableAsOptional is true -- there is some tricky
interaction with failable initializers that still needs to be worked out.
Swift SVN r22548
This commit modifies Sema to add type checking for potentially unavailable
method references. We now record the reason for method unavailability when
recording a potential overload choice during member constraint simplification
and either diagnose or lift to an optional type during CSApply. This commit also
generalizes UnavailableToOptionalExpr to take an arbitrary subexpression.
This commit does not address potentially unavailable properties, initializers,
or dynamic member references.
Swift SVN r22508
This commit also factors out some common checking and diagnostic code; it
additionally moves diagnostic emission for unavailable references from CSGen to
CSApply.
Swift SVN r22447
This commit adds tests to demonstrate that availability checking works,
at the Sema level, for global functions. SILGen for potentially unavailable
global functions is not yet implemented.
Swift SVN r22406
This commit adds tracking of the reason a declaration reference is potentially
unavailable to the UnavailableToOptionalExpr AST node and to OverloadChoice. We
will use this reason during SILGen to emit the appropriate run-time check and
during typechecking to provide more helpful diagnostics.
To keep OverloadChoice as small as possible, we encode the reason as an index
into a vector of reasons stored in a given instance of ConstraintSystem (this is
the same approach that Fix takes).
This commit adds Sema/OverloadChoice.cpp (for the parts of OverloadChoice that
now rely on ConstraintSystem) and AST/Availability.h (to bring in
availability-related structures without TypeRefinementContext).
Swift SVN r22377
This patch adds construction of type refinement contexts for the Then branch of
availability queries and adds diagnostics for ill-formed queries. For the
moment, we do not refine for the Else branch because the version range lattice
is not precise enough to do so helpfully.
This patch does not properly handle availability queries involving application
extension platforms (noted with a FIXME). I will add support for these platforms
in a future commit.
Swift SVN r22165
This patch adds the beginning of building the type refinement context tree for
availability checking in Sema, guarded by by the
-enable-experimental-availability-checking option. This tree parallels the AST
but is much more sparse: we introduce a new TypeRefinementContext only when
needed. Each context refines the range of potential OS versions that could be
encountered at run time. For the moment, we only refine contexts for function
bodies. I will add refinement contexts for #os(...) in a later commit.
The AST is not directly connected to the TRC tree except at the SourceFile
level; when type checking, we use source locations to look up the TRC
corresponding to an AST element. For the moment, we emit a diagnostic when the
programmer references a potentially unavailable declaration. We will later
change this to treat the declaration as if it had optional type.
Swift SVN r22145
