From @masak

* moritz_ found a very weird bug
<moritz_> rakudo​: printf 'foobar'
<p6eval> rakudo 6783b5​: OUTPUT«foobar»
<moritz_> rakudo​: printf '%- 8%s', 'XXX', 'bla'
<p6eval> rakudo 6783b5​: ( no output )
<moritz_> rakudo​: printf '%- 8%s' ~ "\n", 'XXX', 'bla'
<p6eval> rakudo 6783b5​: ( no output )
<masak> what's weird is that it doesn't print anything.
<moritz_> right
<moritz_> it doesn't like the format string
<moritz_> with good reason, I might add
<moritz_> but then it should please die() or fail() or interpret it literally
* masak submits rakudobug
<masak> I've experienced &say do the same lately, I think. but only on
the evalbot.
<masak> this, however, occurs locally too.

@coke - Status changed from 'new' to 'open'

From @Kodiologist

Fixed in a98c690fe14​:

$ ./perl6 -e 'printf "%s\n"'
Not enough arguments supplied for the given format string
  in 'Cool​::sprintf' at line 2683​:CORE.setting
  in 'sprintf' at line 2717​:CORE.setting
  in 'IO​::printf' at line 5479​:CORE.setting
  in 'printf' at line 5670​:CORE.setting
  in main program body at line 1

@Kodiologist - Status changed from 'open' to 'resolved'

From @Kodiologist

I've added a test to S32-str/sprintf.t (roast 207e6b48db).