Replace old GDB and LLDB pretty-printers with new ones
which were originally written for IntelliJ Rust.
New LLDB pretty-printers support synthetic children.
New GDB/LLDB pretty-printers support all Rust types
supported by old pretty-printers, and also support:
Rc, Arc, Cell, Ref, RefCell, RefMut, HashMap, HashSet.
If the rust-enabled lldb was built, then use it when running the
debuginfo tests. Updating the lldb submodule was necessary as this
needed a way to differentiate the rust-enabled lldb, so I added a line
to the --version output.
This adds compiletest commands to differentiate between the
rust-enabled and non-rust-enabled lldb, as is already done for gdb. A
new "rust-lldb" header directive is also added, but not used in this
patch; I plan to use it in #54004.
This updates all the tests.
This is the kind of change that one is expected to need to make to
accommodate overloaded-`box`.
----
Note that this is not *all* of the changes necessary to accommodate
Issue 22181. It is merely the subset of those cases where there was
already a let-binding in place that made it easy to add the necesasry
type ascription.
(For unnamed intermediate `Box` values, one must go down a different
route; `Box::new` is the option that maximizes portability, but has
potential inefficiency depending on whether the call is inlined.)
----
There is one place worth note, `run-pass/coerce-match.rs`, where I
used an ugly form of `Box<_>` type ascription where I would have
preferred to use `Box::new` to accommodate overloaded-`box`. I
deliberately did not use `Box::new` here, because that is already done
in coerce-match-calls.rs.
----
Precursor for overloaded-`box` and placement-`in`; see Issue 22181.
except where trait objects are involved.
Part of issue #15349, though I'm leaving it open for trait objects.
Cross borrowing for trait objects remains because it is needed until we
have DST.
This will break code like:
fn foo(x: &int) { ... }
let a = box 3i;
foo(a);
Change this code to:
fn foo(x: &int) { ... }
let a = box 3i;
foo(&*a);
[breaking-change]
