With the old ABI, we generated a copy of every protocol in every
compilation unit that declared it. We now emit protocols only if they
are referenced (and have the linker deduplicate them).
This test was previously failing with the Apple runtime.
These are currently ignored, because they are only important when the
runtime has upgraded the protocol. The runtime will upgrade legacy
protocols, but they are not referenced by this indirection layer.
We're now using a new class and category structure and auto-upgrading the old ones. Other changes:
- The Ivar structure now points to the ivar offset variable, so we can more easily find it.
- Categories can now add properties.
This probably didn't make a difference, but if we ended up
resolving a class as a result of resolving a subclass, then we'd previously go and explore an unrelated linked list for a bit.
macOS ships with libc++abi, which doesn't provide the hooks required
for interop, so this was causing all of the tests to fail to link in
the Travis macOS test. We're now correctly detecting that it won't
work on macOS and disabling those tests.
Throwing an Objective-C exception through a C++ catch block was broken.
This was because the C++ code inserts a cleanup handler to make sure
that it invokes `__cxa_end_catch`. Unwinding through this catchup
transformed the Objective-C exception into a C++ one. This case should
have been handled, except for two bugs:
1. A typo (`#ifdef` instead of `#ifndef`) meant that we were not
extracting the Objective-C exception from the C++ object.
2. We were skipping everything except catchalls after the search phase,
because we lose some information in the transformation.
Fixes#49
Weak refs were being left as dangling pointers after being deleted. The
load that caused the deallocation would return nil, but then the next
one would dereference a dangling pointer.
Fixes a bug introduced (replacing a similar bug) in the last rewrite of
objc_moveWeak. This version should now be correct.
objc_copyWeak was implemented in a naive way, which had a lot more
overhead than required.
Rather than tracking all of the locations of weak pointers, keep a weak
refcount. This should also make it easier to add finer-grained locking to weak
references.