The last two tests in the NotPresent test check for fixes that went into 5.3. Testing these against earlier runtimes will fail. Add availability checks so we only test when the fix is present.
While we're here, switch the symbolic references test to use indirect references. Direct references are very likely to pass the test even without the fix, as the reference is likely to point to readable memory. Indirect references make this much more likely to crash by then reading and dereferencing a pointer from the memory the relative pointer points to.
rdar://159034772
The demangler tolerates arbitrary suffixes on mangled names, and parses them as a Suffix node. When looking up a class by an ObjC mangled name, we don't want such demanglings to succeed, because this will result in false positives. It's expected that NSClassFromString(someClassName + "some suffix") will fail, unless something has actually created a class with that suffix.
rdar://problem/60012296
We don't want objc_getClass and NSClassFromString to be able to feed arbitrary symbolic reference
pointers into the Swift runtime. Fixes rdar://problem/54724618.
Create a new capturing substitution for adding a rpath to a target
library. This is needed as Windows doesn't really support the concept
of a rpath. This also makes it possible to remove the parameter from
the command line on windows.
Thanks to @jrose for the hint about the substitution ordering, the new
substitution now works even inside the capture group. Replace the
remaining uses to the new macro.
The naming convention is different on Windows than on Unix-like
environments. In order to follow the convention we need to substitute
the prefix and the suffix. Take the opportunity to rename the
`target-dylib-extension` to the CMake-like variable
`target-shared-library-suffix` and introduce
`target-shared-library-prefix`. This helps linking the test suite
binaries on Windows.
libobjc needs to look up classes by name. Some Swift classes, such as
instantiated generics and their subclasses, are created only on demand.
Now a by-name lookup from libobjc counts as a demand for those classes.
rdar://problem/27808571
