as a way to get more type information out of incorrect subexpressions. UnresolvedType
generally just propagates around the type system like a type variable:
- it magically conforms to all protocols
- it CSGens as an unconstrained type variable.
- it ASTPrints as _, just like a type variable.
The major difference is that UnresolvedType can be used outside the context of a
ConstraintSystem, which is useful for CSGen since it sets up several of them to
diagnose subexpressions w.r.t. their types.
For now, our use of this is extremely limited: when a closureexpr has no contextual
type available and its parameters are invalid, we wipe them out with UnresolvedType
(instead of the previous nulltype dance) to get ambiguities later on.
We also introduce a new FreeTypeVariableBinding::UnresolvedType approach for
constraint solving (and use this only in one place in CSDiags so far, to resolve
the callee of a CallExpr) which solves a system and rewrites any leftover type
variables as UnresolvedTypes. This allows us to get more precise information out,
for example, diagnosing:
func r22162441(lines: [String]) {
lines.map { line in line.fooBar() }
}
with: value of type 'String' has no member 'fooBar'
instead of: type of expression is ambiguous without more context
This improves a number of other diagnostics as well, but is just the infrastructural
stepping stone for greater things.
Swift SVN r31105
This changes the behavior to match NominalTypeDecls, which don't have a type
until everything is set up either. In a few places we construct TypeAliasDecls
from known types directly, and we have to call computeType().
Fixes <rdar://problem/19534837>.
Swift SVN r30386
Specifically track when we're resolving type witnesses for a given
conformance, and refuse to recursively attempt to resolve those type
witnesses. The standard library patch in rdar://problem/21789238
triggers this, and isolating it in a small test case has proven
illusive.
Swift SVN r30160
The isDependentType() query is woefully misunderstood. Some places
seem to want it to mean "a generic type parameter of dependent member
type", which corresponds to what is effectively a type parameter in
the language, while others want it to mean "contains a type parameter
anywhere in the type". Tease out these two meanings in
isTypeParameter() and hasTypeParameter(), respectively, and sort out
the callers.
Swift SVN r29945
It looks like we were checking in the wrong place, as a result we didn't
catch stuff like
class G<T : AnyObject> {}
_ = G<P>()
This would crash later in IRGen.
Make the conformsToProtocol() check do the right thing, and remove some
other miscellaneous diagnostics in the process. Also, make the
"type 'T' does not conform to protocol 'P'" diagnostic a bit more
detailed.
Unfortunately in a few instances we lose a more descriptive diagnostic to
a general 'cannot invoke 'foo' with argument list of type 'T'' error. The
argument matching diagnostics need to be addressed anyway though.
Fixes <rdar://problem/20311619>.
Swift SVN r29737
Rename existentialConformsToSelf() to existentialTypeSupported(). This
predicate is the "protocol has no Self or associated type requirements"
check, which is a looser condition than self-conformance. This was being
tested to see if the user could refer to the protocol via an existential
type.
The new existentialConformsToSelf() now checks for protocol being @objc,
and for the absence of static methods. This is used as part of the
argument type matching logic in matchType() to determine if the
existential can be bound to a generic type parameter.
The latter condition is stricter, for two reasons:
1) We allow binding existentials to multiple type parameters all sharing
the same generic type parameter T, so we don't want the user to be
able to see any static methods on T.
2) There is an IRGen limitation whereby only existentials without witness
tables can be passed in this manner.
Using the above, the representsNonTrivialGenericParameter() function
has been renamed to canBindGenericParamToExistential(). It now allows
an existential type to be bound to a generic type parameter only under
the following circumstances:
A) If the generic type parameter has no conformances, the match is allowed.
B) If the generic type parameter has at least one conformance, then all
of the conformances on the generic type parameter must be
existentialConformsToSelf() (condition 1 above), and all conformances
on the existential must be @objc (condition 2 above).
Fixes <rdar://problem/18378390> and <rdar://problem/18683843>, and lays
the groundwork for fixing a few other related issues.
Swift SVN r29337
This is a hack.
We currently don't put anything in Clang submodules; they're just wrappers
to track what is and isn't visible. All lookups happen through the top-
level module.
This commit adds a new API getImportedModulesForLookup, which is ONLY used
by top-level name lookup and forAllVisibleModules. It is identical to
getImportedModules for everything but ClangModuleUnits, which instead
compute and cache a list of their transitively imported top-level modules.
This speeds up building Foundation.swiftmodule with a release compiler by
a bit more than 5%, and makes a previously lookup-bound test case compile
a third faster than before.
This is a hack.
rdar://problem/20813240
Swift SVN r28598
Modules occupy a weird space in the AST now: they can be treated like
types (Swift.Int), which is captured by ModuleType. They can be
treated like values for disambiguation (Swift.print), which is
captured by ModuleExpr. And we jump through hoops in various places to
store "either a module or a decl".
Start cleaning this up by transforming Module into ModuleDecl, a
TypeDecl that's implicitly created to describe a module. Subsequent
changes will start folding away the special cases (ModuleExpr ->
DeclRefExpr, name lookup results stop having a separate Module case,
etc.).
Note that the Module -> ModuleDecl typedef is there to limit the
changes needed. Much of this patch is actually dealing with the fact
that Module used to have Ctx and Name public members that now need to
be accessed via getASTContext() and getName(), respectively.
Swift SVN r28284
Replace the 'ignoreMissing' boolean flag with a new option set type,
SubstOptions, which is easier to extend. It is not an OptionSet<>
because a follow-on commit will introduce a non-trivial option that
will require more storage.
Also eliminate the LazyResolver parameter, which is no longer
needed. Eliminate the silly TypeChecker::substType(), whose only
purpose was to provide the resolver.
Swift SVN r27656
This eliminates nonsensical recursion when working with protocol
conformances, and makes their checking more lazy. Start to improve
name lookup to deal with protocol witnesses more lazily, generalizing
the solution we had to all protocol conformances and making it more
directed. We're not done here, as the FIXMEs in the code completion
test imply: this replace-the-requirement-with-the-witness behavior
needs to be sunk down into the AST level so it also applies to
unqualified lookup, visible-decl lookup, etc.
Swift SVN r27639
LLDB asked for this to differentiate between modules loaded successfully and
modules that are correctly found but can't be loaded for some reason.
rdar://problem/19750055
Swift SVN r27041
getImportedModules is the canonical way to get imports, whether private,
public, or both. This is especially true now that we have more flags
for SourceFile imports that really shouldn't be consumed by anyone
outside of SourceFile.
In this same vein, provide addImports instead of setImports, since imports
are always additive.
No visible functionality change.
Swift SVN r26634
We can now use internal declarations safely and correctly in source files!
The remaining work is to make sure testable imports work reliably through
modules, which is important for debugging unit tests.
It's also possible this work will affect compile time, but for the most
part we don't have large quantities of internal declarations that are
being ignored, and some day we will strip them out of non-testable modules
altogether.
Part of rdar://problem/17732115
Swift SVN r26633
Currently a no-op, but effective access for entities within the current
module will soon need to take testability into account. This declaration:
internal func foo() {}
has a formal access of 'internal', but an effective access of 'public' if
we're in a testable mode.
Part of rdar://problem/17732115 (testability)
Swift SVN r26472
Replace the loop over all known protocols with a query into the
actual conformance lookup table, which more properly deals with
out-of-order conformance queries, inheritance of protocol
conformances, and conformance queries in multi-file situtations.
The SILGen test change is because we're no longer emitting redundant
conformances, while the slight diagnostic regression in
circular-inheritance cases is because we handle circular inheritance
very poorly throughout the compiler.
While not the end, this is a major step toward finishing
rdar://problem/18448811.
Swift SVN r26299
This flag indicates that internal APIs within the module should be made
available to client code for testing purposes. Currently does nothing.
Not ready for developer consumption yet, ergo a hidden frontend-only flag.
Part of testability (rdar://problem/17732115)
Swift SVN r26292
Previously, we would require the type checker to be able to build a
conformance, which meant we would actually have to lie in the AST
about having a conformance (or crash; we did the form). Now, we can
form the conformance in the AST and it will be checked in the type
checker when needed. The intent here is to push conformance creation
into the conformance lookup table.
To get here, we had to stop relying on the broken, awful,
ASTContext-wide conformance "cache". A proper cache can come back once
the model is sorted out.
Swift SVN r26250
Instead of relying on Sema to set the existential-conforms-to-self bit, compute it lazily in the AST. This is far cleaner and more dependable than the previous solution.
Swift SVN r26225
Previously, a multi-pattern var/let decl like:
var x = 4, y = 17
would produce two pattern binding decls (one for x=4 one for y=17). This is convenient
in some ways, but is bad for source reproducibility from the ASTs (see, e.g. the improvements
in test/IDE/structure.swift and test/decl/inherit/initializer.swift).
The hardest part of this change was to get parseDeclVar to set up the AST in a way
compatible with our existing assumptions. I ended up with an approach that forms PBDs in
more erroneous cases than before. One downside of this is that we now produce a spurious
"type annotation missing in pattern"
diagnostic in some cases. I'll take care of that in a follow-on patch.
Swift SVN r26224
Resolving signatures of declarations from files other than the primary source
file causes first-pass type checking, including diagnostics for potential
unavailability, to be performed on those declarations. Prior to this commit, the
type refinement context hierarchy was only constructed for the primary file, so
spurious errors were emitted when checking declarations in other files. With
this commit, the availability checker builds the hierarchy for a source file the
first time its hierarchy is queried. We will eventually want to build the
hierarchy more lazily, but that will come later.
Swift SVN r25746
Easy cut down on exported symbols. Unless a private type is referenced in
an inlineable function, there's no way to generate a reference to it
outside of the current file, except in the debugger. (That last bit is why
we can't use fully private linkage, which would keep the symbol out of the
symbol table completely.)
We should be doing this for "internal" declarations as well, but the
standard library /does/ have references to internal types in inlineable
functions, and also has tests that directly access these types.
Swift SVN r24838
Local type declarations are saved in the source file during parsing,
now serialized as decls. Some of these may be defined in DeclContexts
which aren't Decls and previously weren't serialized. Create four new
record kinds:
* PatternBindingInitializer
* DefaultArgumentInitializer
* AbstractClosureExpr
* TopLevelCodeDecl
These new records are used to only preserve enough information for
remangling in the debugger, and parental context relationships.
Finally, provide a lookup API in the module to search by mangled name.
With the new remangling API, the debugging lifecycle for local types
should be complete.
The extra LOCAL_CONTEXT record will compressed back down in a
subsequent patch.
Swift SVN r24739
PrintAsObjC behaves slightly differently in apps vs. frameworks: for apps,
you get internal decls exposed in the header as well as public ones. This
is because the generated header is not being shipped anywhere and thus we
don't have a secrecy leak.
However, we were detecting whether we were in an app based on whether or
not we had a bridging header. That's no good for mixed-source apps where
there's no bridging header, so now we also check for a main entry point,
whether generated from @UIApplicationMain or @NSApplicationMain, or from
a script source file (main.swift).
rdar://problem/17877235
Swift SVN r24532
This isn't being used for much yet, but it will allow us to tell whether
something is an app target even at the module-merging stage, which is a
better way to tell if something is an app than whether it has a bridging
header.
We'll also need this if we ever take advantage of reusing "partial modules"
(serialized ASTs for other parts of the module that aren't affected by the
current source file) for compiling source files in incremental builds;
unfortunately that's unlikely given our dependency model.
Swift SVN r24531
Rather than keeping just a "main class" in every module, track the "main file"
that's responsible for producing the module's entry point. This covers both
main source files and files containing classes marked @UIApplicationMain or
@NSApplicationMain.
This should have no functionality change, but is preparation for the next
commit, where we will preserve some of this information in serialization.
Swift SVN r24529
This has been long in coming. We always had it in IRGenOpts (in string form).
We had the version number in LangOpts for availability purposes. We had to
pass IRGenOpts to the ClangImporter to actually create the right target.
Some of our semantic checks tested the current OS by looking at the "os"
target configuration! And we're about to need to serialize the target for
debugging purposes.
Swift SVN r24468
Changing the design of this to maintain more local context
information and changing the lookup API.
This reverts commit 4f2ff1819064dc61c20e31c7c308ae6b3e6615d0.
Swift SVN r24432
rdar://problem/18295292
Locally scoped type declarations were previously not serialized into the
module, which meant that the debugger couldn't reason about the
structure of instances of those types.
Introduce a new mangling for local types:
[file basename MD5][counter][identifier]
This allows the demangle node's data to be used directly for lookup
without having to backtrack in the debugger.
Local decls are now serialized into a LOCAL_TYPE_DECLS table in the
module, which acts as the backing hash table for looking up
[file basename MD5][counter][identifier] -> DeclID mappings.
New tests:
* swift-ide-test mode for testing the demangle/lookup/mangle lifecycle
of a module that contains local decls
* mangling
* module merging with local decls
Swift SVN r24426
Previously we reported them once for their base name and once for their
full name, which is unnecessary. All clients were already de-duping, though.
Swift SVN r24051
"private" is a very overloaded term already. "Cascading" instead of
"non-private" is a bit more clear about what will happen with this sort
of lookup.
No functionality change. There are some double negatives I plan to clean
up in the next commit, but this one was supposed to be very mechanical.
Swift SVN r23969
Previously we could fail to capture dependencies on other modules. Why is
this a problem? Because a file in the main module could introduce a new
operator decl with the same name (at least in theory).
Swift SVN r23448
This is sort of two commits squashed into one: first, update
ReferencedNameTracker to record whether a name or type is non-private,
along with changing all clients to assume non-private; and second,
actually try to (conservatively) decide if a particular unqualified lookup can
be considered private.
What does "private" mean? That means that a dependency does not affect
"downstream" files. For example, if file A depends on B, and B depends on C,
then a change in C normally means A will get rebuilt. But if B's dependencies
on C are all private dependencies (e.g. lookups from within function bodies),
then A does not need to be rebuilt.
In practice there are several rules about when we can make this assumption,
and a few places where our current DeclContext model is not good enough to
distinguish private uses from non-private uses. In these cases we have to
be conservative and assume that the use is non-private (and thus that
downstream files will need to be rebuilt).
Part of rdar://problem/15353101
Swift SVN r23447