While one can disable building the embedded stdlib, the tests for that
feature were unconditionally added. If one wants to just build the
compiler without any stdlib (except target), a bunch of embedded tests
would have failed.
Inject the value of `SWIFT_SHOULD_BUILD_EMBEDDED_STDLIB` into the Lit
test system as a feature `embedded_stdlib` and add `REQUIRES:` to
a couple of tests outside the `embedded/` directory that seems to use
the experimental feature. Make the tests in `embedded/` unsupported in
the local Lit configuration file.
The `classes-wasm.swift` test was the only executable test for
WebAssembly that requires wasm runtime at test-time. Other tests
in the `embedded` directory run only on the macOS / Linux host toolchain
builds and some of them are incompatible with SWIFT_SHOULD_BUILD_EMBEDDED_STDLIB=OFF.
Given that the `classes-wasm.swift` test is the only test we want to run
during WasmStdlib build, move it to a separate directory `embedded/wasm`.
At Onone, many types of functions (anything user written, compiler
generated setters and getters, etc), should be kept in the final
binary so they're accessible by the debugger.
rdar://126763340
When testing different linkers, it's sometimes useful to run the tests
with `SWIFT_DRIVER_TEST_OPTIONS=" -use-ld=<linker>"`. If we do this,
it will break a handful of tests because they expect the compiler driver
to choose an appropriate linker automatically.
To avoid having these fail, detect when someone has done this, and
set a new feature, `linker_overridden`, then mark the tests in question
with `UNSUPPORTED: linker_overridden`.
rdar://123504095
We changed to `llvm.compiler.used` because of the behaviour of `gold`,
which refuses to coalesce sections that have different `SHF_GNU_RETAIN`
flags, which causes problems with metadata.
Originally I thought we were going to have to generate two sections
with distinct names and have the runtime look for both of them, but
it turns out that the runtime only wants to see sections that have
`SHF_GNU_RETAIN` in any case. It's really the reflection code that
is interested in being able to see non-retained sections. The upshot
is that we don't need to use `llvm.compiler.used`; it's just fine if
we have duplicate sections, as long as the reflection code looks for
them when it's inspecting an ELF image.
This also means we no longer need to pass `-z nostart-stop-gc` to the
linker if we're using `lld`.
rdar://123504095
Using inconsistent attributes between stdlib and tests causes
compilation errors. There are still several misuses of @_silgen_name in
tests, but leaving them as is for now to incrementally fix them.
