[MacPorts] #59291: librsvg @2.44.14: error[E0506]: cannot assign to `self.input.cached_token` because it is borrowed (was: Bug: librsvg does not build on MacOS 10.15)

[MacPorts]

#59291: librsvg @2.44.14: error[E0506]: cannot assign to `self.input.cached_token`
because it is borrowed
-----------------------+----------------------
  Reporter:  haberg-1  |      Owner:  dbevans
      Type:  defect    |     Status:  assigned
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:  catalina
      Port:  librsvg   |
-----------------------+----------------------
Changes (by ryandesign):

 * keywords:   => catalina


Comment:

 The error shown in the log is:

 {{{
 :info:build error[E0506]: cannot assign to `self.input.cached_token`
 because it is borrowed
 :info:build    -->
 /opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_macports_release_tarballs_ports_graphics_librsvg/librsvg/work/librsvg-2.44.14/vendor/cssparser/src/parser.rs:572:17
 :info:build     |
 :info:build 547 |     pub fn next_including_whitespace_and_comments(&mut
 self) -> Result<&Token<'i>, BasicParseError<'i>> {
 :info:build     |                                                   -
 let's call the lifetime of this reference `'1`
 :info:build ...
 :info:build 560 |             Some(ref cached_token)
 :info:build     |                  ---------------- borrow of
 `self.input.cached_token` occurs here
 :info:build ...
 :info:build 572 |                 self.input.cached_token =
 Some(CachedToken {
 :info:build     |                 ^^^^^^^^^^^^^^^^^^^^^^^ assignment to
 borrowed `self.input.cached_token` occurs here
 :info:build ...
 :info:build 584 |         Ok(token)
 :info:build     |         --------- returning this value requires that
 `self.input.cached_token.0` is borrowed for `'1`
 :info:build error: aborting due to previous error
 :info:build For more information about this error, try `rustc --explain
 E0506`.
 :info:build error: Could not compile `cssparser`.
 }}}

 Perhaps MacPorts updated to a newer version of rust and that broke the
 librsvg build.

-- 
Ticket URL: <https://trac.macports.org/ticket/59291#comment:5>
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