From @LLFourn

role R { method f {...} };

class A { method f { } };

class B does R { has A $.a handles <f>; };

===SORRY!=== Error while compiling -e
Method 'f' must be implemented by B because it is required by a role
at -e​:5

^ it should work.
irc​: http://irclog.perlgeek.de/perl6/2016-09-21#i_13247756

This looks very similar to the problem reported in rakudo/rakudo#2386. There is an extra class in this issue, but it doesn't seem to be relevant for the bug.

The code works nowadays:

$ ./rakudo-m -e 'role R { method f {...} }; class A { method f { } }; class B does R { has A $.a handles <f> }; say "alive"'
alive

According to commitable it has been fixed between 2018.09 and 2018.10 -- so I'm sure it was the fix from rakudo/rakudo#2386.

21:08 < bartolin_> c: 2018.09 role R { method f {...} }; class A { method f { } }; class B does R { has A $.a handles } ## #5687
21:08 < committable6> bartolin_, ¦2018.09: «===SORRY!=== Error while compiling /tmp/r7RcbT9aiB␤Method 'f' must be implemented by B because it is required by roles: R.␤at /tmp/r7RcbT9aiB:1␤ «exit code = 1»»
21:09 < bartolin_> c: 2018.10 role R { method f {...} }; class A { method f { } }; class B does R { has A $.a handles } ## #5687
21:09 < committable6> bartolin_, ¦2018.10: «»

I'd say that the test added to roast with Raku/roast@f3dec0b3c9 covers this issue as well.
So I'll close this as "resolved". (Please reopen if you think this needs a dedicated test.)