If a base method's not available, we already drop the overridding
method. Make sure this works even when the base method is itself
an override that failed to load.
Finishes up the "big four" non-type decl kinds. Unfortunately,
indiscriminately dropping members from a class affects the layout
of its vtable. That issue is tracked by rdar://problem/31878396.
If there's an error deserializing part of a type, just propagate it
out. Also add support for bound generic types. This isn't meant to be
full coverage of possible failures, just ones that are likely to come
up through the C/ObjC importer.
Still to do:
- Generic function types (only show up on functions)
- Unbound generic types (only show up on typealiases, which I may not
even tackle)
Proof-of-concept for the above. This shouldn't be common---renames are
far more likely, and those we can track---but occurs when the
swift_wrapper attribute (the implementation of NS_STRING_ENUM) is
active in Swift 4 but not in Swift 3.
Note that this only checks the canonical interface type of the
declaration, because the non-canonical type may contain references to
the declaration's generic parameters.
This keeps us from showing Swift 3 names in Swift 4 code;
unfortunately, as the test case shows, we still have a few cases where
Swift /4/ names will leak into Swift /3/ code. I'm considering this an
acceptable state of events for now.
Previously we had more ad hoc logic that tried to decide if it was
worth desugaring a type based on its structure. Now we instead look
for a typealias that might actually benefit from desugaring, and if
we don't find one we won't show the 'aka' note.
This is the same as the last few commits, but with the additional
complication of designated initializers affecting other behavior
around the type. In particular, convenience initializers cannot be
invoked on subclasses if the designated initializers are not all
present on the subclass. If a designated initializer is dropped, it's
not possible to satisfy that.
It would be nice to do better here, since a class's initializers are
mostly independent of the superclass's initializers. Unfortunately, it
still affects whether /this/ class can inherit convenience
initializers, as well as vtable layout. This is conservative, at
least.
In order to accomplish this, cross-module references to typealiases
are now banned except from within conformances and NameAliasTypes, the
latter of which records the canonical type to determine if the
typealias has changed. For conformances, we don't have a good way to
check if the typealias has changed without trying to map it into
context, but that's all right---the rest of the compiler can already
fall back to the canonical type.
There are a number of type witnesses that are introduced by the Clang
importer. Immediately resolve those witnesses *without* going through
the type checker, because there are cases (i.e., deserialized SIL)
where the conformance is created but there is no type checker around.
Fixes rdar://problem/30364905, rdar://problem/31053701,
rdar://problem/31565413 / SR-4565.
Like the previous commit, but with added trickiness because we also
serialize the form of the PatternBindingDecl a property came from.
Make getPattern handle a failure in the simple case that overrides
use, and pass that up to the PatternBindingDecl initialization. (This
can result in zero-element PatternBindingDecls, but that's fine.)
'getPattern' is also a change from 'maybeGetPattern', but every caller
knows how many patterns it expects, so accomodating the "maybe" case
is no longer important.
That is, a Swift 3 target imported into a Swift 4 context or vice
versa. This requires serializing the compatibility mode explicitly,
instead of including it in the textual version string that's only
for debugging.
At some point, pass definitions were heavily macro-ized. Pass
descriptive names were added in two places. This is not only redundant
but a source of confusion. You could waste a lot of time grepping for
the wrong string. I removed all the getName() overrides which, at
around 90 passes, was a fairly significant amount of code bloat.
Any pass that we want to be able to invoke by name from a tool
(sil-opt) or pipeline plan *should* have unique type name, enum value,
commend-line string, and name string. I removed a comment about the
various inliner passes that contradicted that.
Side note: We should be consistent with the policy that a pass is
identified by its type. We have a couple passes, LICM and CSE, which
currently violate that convention.
Proof-of-concept for this sort of recovery. In the real world, it's
more likely that this will happen due to differences between Swift 3
and Swift 4, rather than changes in what macros are defined, but the
latter can still happen when debugging.
There's a lot to do here to consider this production-ready. There are
no generics involved and no potential circular references, and the
/rest/ of the compiler isn't prepared for this either. But it's cool
to see it working!
Actually recovering is hidden behind the new
-enable-experimental-deserialization-recovery option; without it the
compiler will continue to eagerly abort.
Also, add a third [serializable] state for functions whose bodies we
*can* serialize, but only do so if they're referenced from another
serialized function.
This will be used for bodies synthesized for imported definitions,
such as init(rawValue:), etc, and various thunks, but for now this
change is NFC.
Follow Clang's lead in defining /System/Library/Frameworks and
/Library/Frameworks as default framework search paths. I'm doing this
manually rather than adding them to the actual list of search paths
because Clang will /also/ do this by default, and I don't want to
needlessly duplicate that work.
rdar://problem/31126655
Filter out any -ivfsoverlay options that include an
unextended-module-overlay.yaml overlay. By convention the Xcode
buildsystem uses these while *building* mixed Objective-C and Swift
frameworks; but they should never be used to *import* the module
defined in the framework.
rdar://problem/30934351
This is like a single-threaded variant of the "lost wakeup
problem" that's all too common to anyone who's worked on
concurrent code.
When we perform lookup into a nominal type, we check if the
ASTContext's generation number is different than a cached
generation number in the nominal type. If the two numbers
differ, we walk over all loaded module files, telling them
to load any serialized extensions. Then we update the cached
generation number in the nominal type to record the fact
that we loaded any outstanding extensions.
The idea is to avoid unnecessary work if we know that no new
extensions have been added since the last name lookup.
The "bottom half" here is that when we add a new serialized
module file, we increment the ASTContext's generation number,
and then add an entry for the module file to a list.
The problem was that in between incrementing the ASTContext's
generation number and adding the module file, we would do some
work involving the ClangImporter which could in turn trigger
name lookup, which would "see" the new generation number in
the ASTContext, but not the new thing that is about to be
added, because it hasn't been added yet. So the
NominalTypeDecl's cached generation number would move forward
and the subsequent add of the module file would be "lost".
Specifically, it looks like when SerializedModuleLoader::loadAST()
calls loadedModuleFile->associateWithFileContext(), which does
some crazy ClangImporter stuff I don't understand, which in
turn can trigger a name lookup.
The fix appears to be to bump the generation number *after*
calling associateWithFileContext().
I don't completely understand what went wrong. For example,
this was dependent on the order of 'import' statements in the
input file. Of the two test cases I added, one the first one
triggered the problem -- the other test case is identical,
except the two import statements are transposed. I'm adding it
to ensure we avoid regressing in this case also.
Also I suspect it is possible to construct a test case that
does not depend on Objective-C interop or Foundation, but
again this looked tricky and I don't think the additional test
coverage on Linux would be worth the effort.
Fixes <rdar://problem/30817732>, so RxSwift now builds again on
master. Yay!
Back in December DougG added code to delay the formation of generic
environments until all declarations from a particular module had been
deserialized, to avoid circular dependencies caused by too-eager
deserialization of protocol members. This worked great for fully-built
modules, but still had some problems with module merging, the phase of
multi-file compilation where the "partial" swiftmodules that
correspond to each source file in a target are loaded and remitted as
a single swiftmodule. Fix this by picking one of the partial
swiftmodules as the representative one for delayed actions, and wait
until deserialization is complete for /all/ of the serialized ASTs in
the same target to form the generic environments.
rdar://problem/30984417
ExtensionDecls for nested generic types have multiple generic parameter
lists, one for each level of nested generic context.
We only serialized the outermost list, though. This didn't cause any
problems as far as I can see because most of the time we seem to use
the GenericSignature instead, which has the correct generic parameters.
However since we still have usages of getGenericParamsOfContext() on
deserialized DeclContexts, better safe than sorry.
I added a test; the test used to pass on master, but with the new
assertion I added, it would fail without the other changes in this
patch.
Instead of appending a character for each substitution, we now prefix the substitution with the repeat count, e.g.
AbbbbB -> A5B
The same is done for known-type substitutions, e.g.
SiSiSi -> S3i
This significantly shrinks mangled names which contain large lists of the same type, like
func foo(_ x: (Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int))
rdar://problem/30707433
This is a bit of a hack to dodge an assertion. In essence, it's a
harmless hack, but we'd like to make the handling of optional and
unavailable requirements more rigorous.
This got reverted because it made our non-deterministic deserialization
crasher come up more often. Re-applying this patch to test the theory
that @jrose-apple's fix addressed the issue.
Replace an existing flag for cross-references to member types (that
wasn't getting much use) with one consistent with how we lookup
values. This fixes the case where someone actually has a useful type
as a member of a protocol extension, and that type gets referenced in
another module; Dispatch does exactly this.
Because you can currently only define typealiases in protocol
extensions, not new types, there's always a workaround for someone
hitting this issue: just use the underlying type.
https://bugs.swift.org/browse/SR-4076
