Controlled with a new flag '-direct-clang-cc1-module-build'
This will allow clients to formulate 'swift-frontend' invocations with fully-specified set of cc1 arguments (using '-Xcc -Xclang -Xcc <FLAG>') required for the PCM build, without having to go through the driver.
Having an out-of-line definition for the LangOptions constructor makes
it easier to enable experimental features one at a time for a build,
without rebuilding everything.
I am separating the concern of weakly linking symbols that are introduced at the deployment target from the concern of type checking this new type of potential unavailability.
Resolves rdar://97925900
Introduce the `-enable-upcoming-feature X` command-line argument to
allow one to opt into features that will be enabled in an upcoming language
mode. Stage in several features this way (`ConciseMagicFile`,
`ForwardTrailingClosures`, `BareSlashRegexLiterals`).
Defined SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY to describe
whether the standard library will use the task-to-thread model for
concurrency. It is true only for freestanding non-Darwin stdlibs.
When it is true, SWIFT_CONCURRENCY_TASK_TO_THREAD_MODEL is defined
during stdlib compilation of both Swift and C++ sources.
Added an option to LangOptions to specify which concurrency model is
used, either standard or task-to-thread. When
SWIFT_STDLIB_TASK_TO_THREAD_MODEL_CONCURRENCY is true, the model is
specified to be task-to-thread.
When developing a module for an OS or SDK, one may use declarations from other modules that were recently introduced in the in-development OS. Those declarations will be annotated as available at the deployment target of the client module and yet the symbols for that declaration are not available in all development builds of that OS. If the module strongly links those symbols, it will crash on older development builds of the OS. The `-enable-experimental-ad-hoc-availability` flag is designed to give developers the option of weakly linking all symbols in other modules that were introduced at the deployment target.
This change introduces the basic change in linking behavior but does not address typechecking. Use of the declarations that are made unavailable in this mode will need to be diagnosed and developers will need a way to detect the unavailability at runtime before use.
Resolves rdar://96011550
Experimental features can only be enabled in non-production (+Asserts)
builds. They can be detected with `hasFeature` in the same manner as
"future" features.
The `-enable-experimental-feature X` flag will also look for future
features by that name, so that when an experimental feature becomes an
accepted future feature, it will still be enabled in the same manner.
Switch variadic generics over to this approach, eliminating the
specific LangOption for it.
The `VersionTuple` API was changed llvm/llvm-project
219672b8dd06c4765185fa3161c98437d49b4a1b to return `VersionTuple`
from `get*Version` rather than pass in major, minor, and subminor output
parameters. Update uses to the new API.
Note that `getMacOSXVersion` is slightly different in that it returns a
boolean while taking a `VersionTuple` output parameter to match its
previous behaviour. There doesn't seem to be any use that actually
checks this value though, so we should either update the API to return
an `Optional` and actually check it *or* remove the "failure" case and
return a `VersionTuple` like all the others.
The three options are now:
* `explicit`: Enforce Sendable constraints where it has been explicitly adopted and perform actor-isolation checking wherever code has adopted concurrency. (This is the default)
* `targeted`: Enforce Sendable constraints and perform actor-isolation checking wherever code has adopted concurrency, including code that has explicitly adopted Sendable.
* `complete`: Enforce Sendable constraints and actor-isolation checking throughout the entire module.
