The frontend option '-clang-header-expose-module' allows the user to specify that APIs from an imported module have been exposed in another generated header, and thus APIs that depend on them can be safely exposed in the current generated header.
Once the API has gone through Swift Evolution, we will want to implicitly
import the _Backtracing module. Add code to do that, but set it to off
by default for now.
rdar://105394140
This mode allows the user to fallback to the old behavior that required @expose annotations, while still having standard library interfaces emitted in one header
Add '-validate-clang-modules-once' and '-clang-build-session-file' corresponding to Clang's '-fmodules-validate-once-per-build-session' and '-fbuild-session-file='. Ensure they are propagated to module interface build sub-invocations.
We require these to be first-class Swift options in order to ensure they are propagated to both: ClangImporter and implicit interface build compiler sub-invocations.
Compiler portion of rdar://105982120
Use the new "grouped diagnostics" feature of the swift-syntax
diagnostic rendering to emit printed diagnostics under the
swift-syntax diagnostic style. This emits macro expansion buffers as
text to the terminal, inset in a box where the macro was expanded, so
that there is more context for understanding how the macro was
expanded and what went wrong inside it.
Add an option to `sil-opt` to pass along VFS overlay files to the clang
importer. This is required to make the tests pass with the upcoming
work to avoid modifying the Visual Studio installation and instead to
prefer to inject the content via VFS overlays.
Since https://github.com/apple/swift/pull/63178 added support for Clang modules in the explicit module map, it is possible for there to be multiple modules with the same name: a Swift module and a Clang module. The current parsing logic just overwrites the corresponding entry module in a hashmap so we always only preserved the module that comes last, with the same name.
This change separates the parsing of the modulemap JSON file to produce a separate Swift module map and Clang module map. The Swift one is used by the 'ExplicitSwiftModuleLoader', as before, and the Clang one is only used to populate the ClangArgs with the requried -fmodule-... flags.
If a module was first read using the adjacent swiftmodule and then
reloaded using the swiftinterface, we would do an up to date check on
the adjacent module but write out the unit using the swiftinterface.
This would cause the same modules to be indexed repeatedly for the first
invocation using a new SDK. On the next run we would instead raad the
swiftmodule from the cache and thus the out of date check would match
up.
The impact of this varies depending on the size of the module graph in
the initial compilation and the number of jobs started at the same time.
Each SDK dependency is re-indexed *and* reloaded, which is a drain on
both CPU and memory. Thus, if many jobs are initially started and
they're all going down this path, it can cause the system to run out of
memory very quickly.
Resolves rdar://103119964.
Do this by computing a transitive closure on the computed dependency graph, relying on the fact that it is a DAG.
The used algorithm is:
```
for each v ∈ V {
T(v) = { v }
}
for v ∈ V in reverse topological order {
for each (v, w) ∈ E {
T(v) = T(v) ∪ T(w)
}
}
```
Add frontend flag `-emit-macro-expansion-files diagnostics` to emit any
macro expansion buffers referenced by diagnostics into files in a
temporary directory. This makes debugging type-checking failures in
macro expansions far easier, because you can see them after the
compiler process has exited.
Introduce a new flag `-export-as` to specify a name used to identify the
target module in swiftinterfaces. This provides an analoguous feature
for Swift module as Clang's `export_as` feature.
In practice it should be used when a lower level module `MyKitCore` is
desired to be shown publicly as a downstream module `MyKit`. This should
be used in conjunction with `@_exported import MyKitCore` from `MyKit`
that allows clients to refer to all services as being part of `MyKit`,
while the new `-export-as MyKit` from `MyKitCore` will ensure that the
clients swiftinterfaces also use the `MyKit` name for all services.
In the current implementation, the export-as name is used in the
module's clients and not in the declarer's swiftinterface (e.g.
`MyKitCore`'s swiftinterface still uses the `MyKitCore` module name).
This way the module swiftinterface can be verified. In the future, we
may want a similar behavior for other modules in between `MyKitCore` and
`MyKit` as verifying a swiftinterface referencing `MyKit` without it
being imported would fail.
rdar://103888618
This lets users of `-explicit-swift-module-map-file` use a single mapping
for all module dependencies, regardless of whether they're Swift or Clang
modules, instead of manually splitting them among this file and command
line flags.
The SwiftDiagnostics module within swift-syntax has a diagnostic
pretty-printer that does a nice rendering of the source code with
diagnostics placed inside gaps between the code lines.
Introduce another `-diagnostic-style` argument, `swift-syntax`,
to bridge from the pretty-printed C++ diagnostics over to the
swift-syntax diagnostics engine.
If the json file doesn't contain a value for this, this was never set,
which results in UB.
Unfortunately clang doesn't warn about this but gcc does https://godbolt.org/z/M3sdE73zs
Introduces a concept of a dependency scanning action context hash, which is used to select an instance of a global dependency scanning cache which gets re-used across dependency scanning actions.
Currently headers produced with `-emit-objc-header` /
`-emit-objc-header-path` produce headers that include modular imports.
If the consumer wishes to operate without modules enabled, these headers
cannot be used. This patch introduces a new flag
(`-emit-clang-header-nonmodular-includes`) that when enabled
attempts to argument each modular import included in such a header with
a set of equivalent textual imports.
Currently headers produced with `-emit-objc-header` /
`-emit-objc-header-path` produce headers that include modular imports.
If the consumer wishes to operate without modules enabled, these headers
cannot be used. This patch introduces a new flag
(`-emit-clang-header-nonmodular-includes`) that when enabled
attempts to argument each modular import included in such a header with
a set of equivalent textual imports.
Ambiguities are introduced in generated swiftinterfaces when a type
shares a name with a module (i.e. XCTest). This workaround uses the
module-alias feature to avoid these ambiguities. Writing module
references with a distinguishable prefix should allow normal
type-checking to avoid the usual ambiguities.
We should still aim for a proper fully-qualified named syntax, but this
may help in the mean time.
rdar://101969500
Allow user-defined macros to be loaded from dynamic libraries and evaluated.
- Introduce a _CompilerPluginSupport module installed into the toolchain. Its `_CompilerPlugin` protocol acts as a stable interface between the compiler and user-defined macros.
- Introduce a `-load-plugin-library <path>` attribute which allows users to specify dynamic libraries to be loaded into the compiler.
A macro library must declare a public top-level computed property `public var allMacros: [Any.Type]` and be compiled to a dynamic library. The compiler will call the getter of this property to obtain and register all macros.
Known issues:
- We current do not have a way to strip out unnecessary symbols from the plugin dylib, i.e. produce a plugin library that does not contain SwiftSyntax symbols that will collide with the compiler itself.
- `MacroExpansionExpr`'s type is hard-coded as `(Int, String)`. It should instead be specified by the macro via protocol requirements such as `signature` and `genericSignature`. We need more protocol requirements in `_CompilerPlugin` to handle this.
- `dlopen` is not secure and is only for prototyping use here.
Friend PR: apple/swift-syntax#1022
Intro ASTContext::setIgnoreAdjacentModules to change module loading to
accept load only resilient modules from their swiftinterfaces, ignoring
the adjacent module and any silencing swiftinterfaces errors.
The relationship between the code in these two libraries was fundamentally circular, indicating that they should not have been split. With other changes that I'm making to remove circular dependencies from the CMake build graph I eventually uncovered that these two libraries were required to link each other circularly, but that had been hidden by other cycles in the build graph previously.
