This allows us to eliminate a comparison;
https://github.com/swiftlang/swift/pull/83172 will allow the compiler to
do it for us instead in the future.
**Explanation:** Changes the implementation of Span's subscript bounds
checks to use a single unsigned comparison instead of two signed
compares.
**Scope:** Narrow. Does not apply to any other API.
**Issues:** rdar://156068535
**Original PRs:** https://github.com/swiftlang/swift/pull/83150
**Risk:** Low. Minor implementation tweaks to API that is not widely
adopted.
**Testing:** CI
**Reviewers:** @glessard @meg-gupta
Most of linkers pull object files from static archives only if any
symbol from that object file is referenced, even if the object contains
a ctor code. `Setup.cpp` didn't have any symbols referenced from
other code, so it was not linked in when the concurrency runtime was
linked in statically. This commit moves the ctor code to `Task.cpp`
to ensure that it is always linked in.
Add an extra opaque field to AddressSpace, which can be used by clients
of RemoteInspection to distinguish between different address spaces.
LLDB employs an optimization where it reads memory from files instead of
the running process whenever it can to speed up memory reads (these can
be slow when debugging something over a network). To do this, it needs
to keep track whether an address originated from a process or a file. It
currently distinguishes addresses by setting an unused high bit on the
address, but because of pointer authentication this is not a reliable
solution. In order to keep this optimization working, this patch adds an
extra opaque AddressSpace field to RemoteAddress, which LLDB can use on
its own implementation of MemoryReader to distinguish between addresses.
This patch is NFC for the other RemoteInspection clients, as it adds
extra information to RemoteAddress, which is entirely optional and if
unused should not change the behavior of the library.
Although this patch is quite big the changes are largely mechanical,
replacing threading StoredPointer with RemoteAddress.
rdar://148361743
(cherry picked from commit 58df5534d2)
(cherry picked from commit 8f3862b5e7)
- Move the definition of 'structured concurrency' to the beginning of
the section.
- Avoid future tense. Fix some mixed future+present tense errors.
- Write bullet points as individual sentences, not as the clauses of one
long sentence.
- Apple Style: Use 'since' only in the sense of 'after'.
- Apple Style: Use 'you' instead of 'one'.
- Apple Style: Close up 'non-' except when ambiguous.
- DevPubs style: Avoid bare 'this' for clarity. Here, 'this guarantee'
tells the reader what 'this' refers to.
- DevPubs style: Avoid 'may' which can be ambiguous between possibility
and permission.
Explanation:
This ensures a potential leak with SwiftUI and other systems using
Observation do not leak observation closures when the potential
Observable instances used are only weakly referenced inside the tracking
closure.
Scope:
This is limited to the runtime behavior of Observable types and has no
ABI or language level interactions.
Issues:
rdar://112167556
Original PRs:
https://github.com/swiftlang/swift/pull/79823https://github.com/swiftlang/swift/pull/82307
Risk:
Low - This is very targeted to just Observation, however it is a
behavioral change which does not make this a zero risk change.
Testing:
New unit tests were added to catch at least some of the potential cases
this issue can occur with.
