From @masak

<timotimo> p6​: sub foobar() { say "i've done it!" }; &foobar;
<camelia> rakudo-parrot 1aeb7c, rakudo-jvm 1aeb7c, rakudo-moar 1aeb7c,
niecza v24-109-g48a8de3​: ( no output )
<timotimo> why no "useless use of &foobar in sink context"?
<timotimo> p6​: sub foobar() { say "i've done it!" }; &foobar; 1;
<camelia> rakudo-parrot 1aeb7c, rakudo-jvm 1aeb7c, rakudo-moar 1aeb7c,
niecza v24-109-g48a8de3​: ( no output )
<moritz> well, we have a known bug that the last statement doesn't get
compile-time sunk
<moritz> but with trailing ;1 it rally should
<moritz> oh, I think I know why
<moritz> because otherwise, sub foo { } might also warn :-)
<timotimo> well, sub foo { } is a declaration, though
<timotimo> and &foo is just a mention
<timotimo> so that should be differentiable
<moritz> it should be, yes
<timotimo> masak​: feel like submitting this LTA rakudobug? :)
<timotimo> though it's not quite as nasty as in python
<timotimo> where lack of () directly means mention instead of use
<moritz> same in JS and C
<timotimo> in perl 6 you have to do a bit of extra work to get a
mention instead of a use
* masak submits rakudobug

From @TimToady

fixed in 323a5c077efeaa058de48871963046507e33b272

@TimToady - Status changed from 'new' to 'resolved'