@differentiable function is actually a triple (function, jvp, vjp). Previously normal thick function value witness table was used. As a result, for example, only function was copied, but none of differential components.
This was the cause of uninitialized memory accesses and subsequent segfaults.
Should fix now unavailable TF-1122
Swift vtables can contain NULL entries. This happens when the compiler is able to prove that a method is never called.
When ptrauth is enabled, those NULL entries are still signed. However, there's an inconsistency in the runtime. Most places where we copy a vtable with swift_ptrauth_copy_code_or_data, we accept an unsigned NULL value. But when fixing up a dynamic ObjC subclass with swift_objc_classCopyFixupHandler, we don't.
Since the compiler seems to always sign these NULL values, this still works, except in the case where a signed NULL value coincidentally has a ptrauth signature of all zeroes. When that happens, the code to accept an unsigned NULL value sees this NULL with an all-zero signature as an unsigned NULL, and copies it verbatim. Then we really do have an unsigned NULL in the destination.
If that class is then dynamically subclassed, we'll call swift_objc_classCopyFixupHandler which does not accept unsigned NULL values, and fail ptrauth.
Adjust swift_objc_classCopyFixupHandler to accept unsigned NULL like the rest. These entries should never be called, and any attempt to call them will crash regardless, so it makes little difference.
rdar://92800322
Upgrade the old mangling from a list of argument types to a
list of requiremnets. For now, only same-type requirements
may actually be mangled since those are all that are available
to the surface language.
Reconstruction of existential types now consists of demangling (a list of)
base protocol(s), decoding the constraints, and converting the same-type
constraints back into a list of arguments.
rdar://96088707
We were skipping shared cache queries if the ObjC metadata or descriptor were outside the shared cache, but we need to skip only if they're both outside the shared cache. We also need to check foreign types even if the descriptor is outside the shared cache.
rdar://93931813
Return a NULL demangle tree instead of crashing. When an unconditional
runtime cast fails, it's going to crash anyways, but this way it prints
a better description (though not great) than the unreachable's message here.
The fix here is two-fold:
1) Teach SILGen that it cannot use the scalar casting paths for extended existentials
2) Teach the runtime casting entrypoint to unwrap as much metatype structure as possible
before arriving at a 'Self' type bound for the requirement checking paths.
The code here mirrors the destructuring check we're doing in remote mirrors.
rdar://95166916
Implement casting to and from extended existentials. This is done by slightly generalizing the conditional conformances checking infrastructure.
Unfortunately, casts for reference types and metatypes are unsound because IRGen is peepholing all non-opaque existential conversions with a helper. I’ll disable that in a follow-up.
rdar://92197049
On Linux it seems that the linker objects, probably because of link order,
to the definition of `swift::threading::fatal()` being in both static
libraries. Fix by moving `swift::threading::fatal()` to its own file
in the main runtime as well as the Concurrency runtime.
Fixes#59444.
There's no guarantee that e.g. pthread_key_t is an integral type. It could
be some kind of struct, or some other thing that isn't valid as a template
argument.
rdar://90776105
We shouldn't include <windows.h> implicitly from .cpp files, but should
do it directly so that we know it's there.
Also, if we're including <windows.h>, do it at the top of the file.
rdar://90776105
Moved all the threading code to one place. Added explicit support for
Darwin, Linux, Pthreads, C11 threads and Win32 threads, including new
implementations of Once for Linux, Pthreads, C11 and Win32.
rdar://90776105
SWIFT_STDLIB_SINGLE_THREADED_RUNTIME is too much of a blunt instrument here.
It covers both the Concurrency runtime and the rest of the runtime, but we'd
like to be able to have e.g. a single-threaded Concurrency runtime while
the rest of the runtime is still thread safe (for instance).
So: rename it to SWIFT_STDLIB_SINGLE_THREADED_CONCURRENCY and make it just
control the Concurrency runtime, then add a SWIFT_STDLIB_THREADING_PACKAGE
setting at the CMake/build-script level, which defines
SWIFT_STDLIB_THREADING_xxx where xxx depends on the chosen threading package.
This is especially useful on systems where there may be a choice of threading
package that you could use.
rdar://90776105
The operator new/delete overrides aren't working out due to inconsistent inlining of std::string creation/deletion. We can end up creating one with the global new but destroying it with our local delete. If they aren't compatible, this crashes.
Instead, avoid problematic new/delete activity coming from lookup of ObjC class names. Names passed to getObjCClassByMangledName must either have a standard mangled name prefix, start with a digit (for unprefixed mangled names) or use the convenience dot syntax. Check for those up front and immediately reject anything else. This has the added bonus of failing more quickly for non-Swift names.
rdar://93863030
There's no guarantee that e.g. pthread_key_t is an integral type. It could
be some kind of struct, or some other thing that isn't valid as a template
argument.
rdar://90776105
We shouldn't include <windows.h> implicitly from .cpp files, but should
do it directly so that we know it's there.
Also, if we're including <windows.h>, do it at the top of the file.
rdar://90776105
Moved all the threading code to one place. Added explicit support for
Darwin, Linux, Pthreads, C11 threads and Win32 threads, including new
implementations of Once for Linux, Pthreads, C11 and Win32.
rdar://90776105
SWIFT_STDLIB_SINGLE_THREADED_RUNTIME is too much of a blunt instrument here.
It covers both the Concurrency runtime and the rest of the runtime, but we'd
like to be able to have e.g. a single-threaded Concurrency runtime while
the rest of the runtime is still thread safe (for instance).
So: rename it to SWIFT_STDLIB_SINGLE_THREADED_CONCURRENCY and make it just
control the Concurrency runtime, then add a SWIFT_STDLIB_THREADING_PACKAGE
setting at the CMake/build-script level, which defines
SWIFT_STDLIB_THREADING_xxx where xxx depends on the chosen threading package.
This is especially useful on systems where there may be a choice of threading
package that you could use.
rdar://90776105
Swift 5.7 added stronger index validation for `String`, so some illegal cases that previously triggered inconsistently diagnosed out of bounds accesses now result in reliable runtime errors. Similarly, attempts at applying an index originally vended by a UTF-8 string on a UTF-16 string now result in a reliable runtime error.
As is usually the case, new traps to the stdlib exposes code that contains previously undiagnosed / unreliably diagnosed coding issues.
Allow invalid code in binaries built with earlier versions of the stdlib to continue running with the 5.7 library by disabling some of the new traps based on the version of Swift the binary was built with.
In the case of an index encoding mismatch, allow transcoding of string storage regardless of the direction of the mismatch. (Previously we only allowed transcoding a UTF-8 string to UTF-16.)
rdar://93379333
On Darwin, define our own, hidden operator new/delete implementations. We don't want to pick up any overrides that come from other code, but we also don't want to expose our overrides to any other code. We can't do this directly in C++, as the compiler has an implicit prototype with default visibility. However, if we implement them as C functions using the C++ mangled names, the compiler accepts them without complaint, and the linker still links all internal uses with these overrides.
rdar://92795919
The shared cache tables can only point to things within the shared cache, so if the protocol, ObjC class, or type descriptor are outside the shared cache, we know that the lookup will fail and we can skip it.
rdar://90427793
