Re: [Sbcl-devel] False compiler note "deleting unreachable code" with Slime

[Nikodemus S. <nik...@ra...>]

On 24 June 2013 17:57, Teemu Likonen <tli...@ik...> wrote:

>> It means something in the expression SORT expands into is unreachable.
>
> Is there some sense the note or is it false?

It is correct. The SPACE 0 cause the SORT call to expand essentially into

  (etypecase seq
   (list (sort-list ...))
   (vector (sort-vector ...))
   (sequence (sort-generic-sequence ...)))

If the assignment is in place, the compiler figures out you have a
list, and the VECTOR and SEQUENCE branches get deleted. Hence the
compiler note.

It is suboptimal, though: not something a user should care about, and
the possibly MAYBE-INLINE declaration for SORT should be replaced by a
deftransform which would also remove the note, and allow eliding
runtype dispatch in higher-space policies when the information is
there.

Anyhow, not a bug per se.

Cheers,

 -- nikodemus