Building (deleted) Waterfox 56.2.8: error: missing documentation for macro

[Graham Perrin]

My last successful build was of ~56.2.7.1. Build ID, mid-February:

20190213143714

56.2.7.1 no longer builds, and I can't build recently released 56.2.8.

Below: the tail of a log file for 56.2.8. Two patch files were set aside 
prior to the build:

$ ls -hl /usr/local/poudriere/ports/default/www/waterfox/files/setaside/
total 18
-rw-r--r--  1 root  wheel   2.1K 17 Mar 13:04 patch-bug1395486
-rw-r--r--  1 root  wheel   801B 17 Mar 13:04 patch-bug1447519
$

Seeing 'servo', I imagine no easy workaround for this, but I'm open to 
friendly suggestions :-)

==== tail of
==== 
/usr/local/poudriere/data/logs/bulk/head-default/2019-03-17_13h16m39s/logs/waterfox-56.2.8.log

    Compiling style_derive v0.0.1 
(/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_derive)
warning: use of deprecated item 'core::str::<impl 
str>::trim_right_matches': superseded by `trim_end_matches`
    --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_derive/to_css.rs:157:29
     |
157 |     camel_case = camel_case.trim_right_matches('_');
     |                             ^^^^^^^^^^^^^^^^^^
     |
     = note: #[warn(deprecated)] on by default

warning: use of deprecated item 'std::ascii::AsciiExt': use inherent 
methods instead
  --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/selectors/attr.rs:7:30
   |
7 | #[allow(unused_imports)] use std::ascii::AsciiExt;
   |                              ^^^^^^^^^^^^^^^^^^^^
   |
   = note: #[warn(deprecated)] on by default

warning: use of deprecated item 'std::ascii::AsciiExt': use inherent 
methods instead
   --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/selectors/parser.rs:16:30
    |
16 | #[allow(unused_imports)] use std::ascii::AsciiExt;
    |                              ^^^^^^^^^^^^^^^^^^^^

    Compiling style_traits v0.0.1 
(/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_traits)
warning: use of deprecated item 'std::ascii::AsciiExt': use inherent 
methods instead
   --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_traits/viewport.rs:10:30
    |
10 | #[allow(unused_imports)] use std::ascii::AsciiExt;
    |                              ^^^^^^^^^^^^^^^^^^^^
    |
    = note: #[warn(deprecated)] on by default

error: missing documentation for macro
    --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_traits/values.rs:341:1
     |
341 | macro_rules! define_css_keyword_enum {
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     |
note: lint level defined here
    --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_traits/lib.rs:12:22
     |
12  | #![deny(unsafe_code, missing_docs)]
     |                      ^^^^^^^^^^^^

error: missing documentation for macro
    --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_traits/values.rs:385:1
     |
385 | macro_rules! __define_css_keyword_enum__add_optional_traits {
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: missing documentation for macro
    --> 
/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/servo/components/style_traits/values.rs:394:1
     |
394 | macro_rules! __define_css_keyword_enum__actual {
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 3 previous errors

error: Could not compile `style_traits`.
warning: build failed, waiting for other jobs to finish...
error: build failed
gmake[4]: *** 
[/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/config/rules.mk:999: 
force-cargo-library-build] Error 101
gmake[4]: Leaving directory 
'/wrkdirs/usr/ports/www/waterfox/work/.build/toolkit/library/rust'
gmake[3]: *** 
[/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/config/recurse.mk:73: 
toolkit/library/rust/target] Error 2
gmake[3]: Leaving directory '/wrkdirs/usr/ports/www/waterfox/work/.build'
gmake[2]: *** 
[/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/config/recurse.mk:33: 
compile] Error 2
gmake[2]: Leaving directory '/wrkdirs/usr/ports/www/waterfox/work/.build'
gmake[1]: *** 
[/wrkdirs/usr/ports/www/waterfox/work/Waterfox-56.2.8/config/rules.mk:453: 
all] Error 2
gmake[1]: Leaving directory '/wrkdirs/usr/ports/www/waterfox/work/.build'
*** Error code 1

Stop.
make: stopped in /usr/ports/www/waterfox
=>> Cleaning up wrkdir
===>  Cleaning for waterfox-56.2.8
build of www/waterfox | waterfox-56.2.8 ended at Sun Mar 17 13:46:41 GMT 
2019
build time: 00:29:46
!!! build failure encountered !!!