Unfortunately using the convenient "bootstrapping0-all", etc. custom targets does not work.
For some reason it does not cause a dependent file (like libswift's SIL.o) being rebuilt when a depenency (like swift-frontend from the previous bootstrapping stage) changes.
Instead we have to list al library- and executable-targets explicitly.
swiftDarwin and swiftOnoneSupport didn't depend on building the Swift core library.
This was a subtle bug, because the compiler just picked up the module from the SDK instead of the (still building) Swift module.
It only resulted in compiler errors if the SDK swiftinterface was too new to be parsable by the compiler.
Don't build the swiftCore module files in the bootstrapping phases. Instead use the module files in the SDK.
This reduces the build time overhead from 3min -> 30seconds.
The SwiftDriver searches `swift-frontend` based on `Bundle.main.executablePath` (which internally uses `CFGetProcessPath`). This search dir is resolved differently on macOS and Linux so swift-frontend can't be found on Linux, forcing the driver to fallback to using the host system toolchain instead of the just-built one.
Adding build modes for libswift: off, hosttools, bootstrapping, bootstrapping-with-hostlibs
The two bootstrapping modes are new. For details see libswift/README.md
This will make sure that compiler developers are using the new driver when they build the compiler locally and use it.
- Adds a new build-script product category: before_build_script_impl for products we wish to build before the impl products.
- Adds a new EarlySwiftDriver product to that category, which gets built with the host toolchain.
- Adds an escape hatch: --skip-early-swift-driver
- Adjusts the swift CMake configuration with an additional step: swift_create_early_driver_symlinks which (if one was built) creates symlinks in the swift build bin directory to the EarlySwiftDriver swift-driver and swift-help executables.
- Adds a new test subset : only_early_swiftdriver, which will get built into a corresponding CMake test target: check-swift-only_early_swiftdriver-* which runs a small subset of driver-related tests against the Early SwiftDriver.
- This subset is run always when the compiler itself is tested (--test is specified)
- With an escape disable-switch: --skip-test-early-swift-driver
- All tests outside of only_early_swiftdriver are forced to run using the legacy C++ driver (to ensure it gets tested, still).
NOTE: SwiftDriver product (no 'Early') is still the main product used to build the driver for toolchain installation into and for executing the product's own tests. This change does not affect that.
The main action here is to sink the creation of the installation rule for all of
the swift host tools into this API. In a latter commit, I will use this API to
create include and build rules for add_swift_host_tool.
This is a flexible way to assert that a binary operation succeeds. For
instance to precondition equality:
precondition(EQUAL FOO BAR)
or string equality:
precondition(STREQUALS FOO BAR)
Since cmake is so loosely typed, it is really important that we
precondition as much as possible to ensure sane behavior.
The contents of that .cmake file are cmake utility functions. Move them into
SwiftUtils.cmake, a file that contains cmake utility functions. This is just a
quick cleanup.
