Unable to compile with rust 1.47

[harto]

I encountered this error compiling the program on macOS:

$ cargo build --release
   [lots of output omitted]

   Compiling syntex_syntax v0.39.0
error[E0713]: borrow may still be in use when destructor runs
   --> /Users/stuart/.cargo/registry/src/github.com-1ecc6299db9ec823/url-1.7.0/src/form_urlencoded.rs:261:40
    |
259 | impl<'a> Target for ::UrlQuery<'a> {
    |      -- lifetime `'a` defined here
260 |     fn as_mut_string(&mut self) -> &mut String { &mut self.url.serialization }
261 |     fn finish(self) -> &'a mut ::Url { self.url }
    |                                        ^^^^^^^^ - here, drop of `self` needs exclusive access to `*self.url`, because the type `UrlQuery<'_>` implements the `Drop` trait
    |                                        |
    |                                        returning this value requires that `*self.url` is borrowed for `'a`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0713`.
error: could not compile `url`.

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error[E0502]: cannot borrow `cx.parse_sess.span_diagnostic` as immutable because it is also borrowed as mutable
   --> /Users/stuart/.cargo/registry/src/github.com-1ecc6299db9ec823/syntex_syntax-0.39.0/src/ext/expand.rs:659:25
    |
649 |         let mut expander = MacroExpander::new(&mut cx);
    |                                               ------- mutable borrow occurs here
...
659 |         let err_count = cx.parse_sess.span_diagnostic.err_count();
    |                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ immutable borrow occurs here
660 |         let mut ret = expander.fold_crate(c);
    |                       -------- mutable borrow later used here

error: aborting due to previous error

For more information about this error, try `rustc --explain E0502`.
error: build failed

I installed rust via Homebrew:

$ rustc -V
rustc 1.47.0

I don't know much about the rust ecosystem, but I was able to compile and run this program at some point in the past 😅