This commit removes the reexports of `old_io` traits as well as `old_path` types
and traits from the prelude. This functionality is now all deprecated and needs
to be removed to make way for other functionality like `Seek` in the `std::io`
module (currently reexported as `NewSeek` in the io prelude).
Closes#23377Closes#23378
- Fixed a couple of dead code warnings in std::sys::backtrace.
- Made `backtrace-debuginfo` test a no-op on non-Linux platforms.
- `backtrace-debuginfo` is no longer tested on pretty-rpass.
Fixes#20978 for supported platforms (i.e. non-Android POSIX).
This uses `backtrace_pcinfo` to inspect the DWARF debug info
and list the file and line pairs for given stack frame.
Such pair is not unique due to the presence of inlined functions
and the updated routine correctly handles this case.
The code is modelled after libbacktrace's `backtrace_full` routine.
There is one known issue with this approach. Macros, when invoked,
take over the current frame and shadows the file and line pair
which has invoked a macro. In particular, this makes many panicking
macros a bit harder to inspect. This really is a debuginfo problem,
and the backtrace routine should print them correctly with
a correct debuginfo.
