Functions like withUnsafeBufferPointer are, by themselves, safe to
call. It's only the operations on the unsafe pointers passed into the
closure that are the safety issue.
This was the intent spelled out in SE-0458 but was not fully realized
in the library.
Fixes rdar://174519372.
Where we have rethrowing versions of functions that have typed-throws
counterparts that are only retained for ABI compatibility, wrap them
in `#if !$Embedded` so they aren't compiled into the Embedded version
of the standard library. This eliminates warnings about this code,
which cannot actually be used with arbitrary errors anyway.
The check for the special case if the sequence is an Array was disabled in embedded swift.
It can be enabled because we now remove the cast after specialization.
Saves some code size when appending one array to another array.
So far the semantic annotation was just added to the internal `_getCount` function.
But for FixedArray it is also required to add the `@_semantics("array.get_count")` to the public API.
This isn't a "complete" port of the standard library for embedded Swift, but
something that should serve as a starting point for further iterations on the
stdlib.
- General CMake logic for building a library as ".swiftmodule only" (ONLY_SWIFTMODULE).
- CMake logic in stdlib/public/core/CMakeLists.txt to start building the embedded stdlib for a handful of hardcoded target triples.
- Lots of annotations throughout the standard library to make types, functions, protocols unavailable in embedded Swift (@_unavailableInEmbedded).
- Mainly this is about stdlib functionality that relies on existentials, type erasure, metatypes, reflection, string interpolations.
- We rely on function body removal of unavailable functions to eliminate the actual problematic SIL code (existentials).
- Many .swift files are not included in the compilation of embedded stdlib at all, to simplify the scope of the annotations.
- EmbeddedStubs.swift is used to stub out (as unavailable and fatalError'd) the missing functionality.
Types that have "value semantics" should not have lexical lifetimes.
Value types are not expected to have custom deinits. Are not expected to
expose unsafe interior pointers. And cannot have weak references because
they are structs. Therefore, deinitialization barriers are irrelevant.
rdar://107076869
Guillaume Lessard
Doug Gregor
Karoy Lorentey
Rick van Voorden
Stephen Canon
Meghana Gupta
Artem Chikin
Meghana Gupta
Hamish Knight
David Smith
Minseong Kim
Erik Eckstein
Kuba Mracek
Lucy Satheesan
Nate Chandler