bug#55355: TBD: inappropriate inlining, cmacro errors

bug#55355: TBD: inappropriate inlining, cmacro errors

[Ivan Sokolov]

Hi all! I encountered inlining errors, unfortunately I have no idea what
is causing them.

Here is the code:

(cl-defstruct (foo (:constructor foo<-list ((bar _ baz))))
  bar
  baz)

(foo<-list '(1 2 3))                    ; does not work

(funcall #'foo<-list '(1 2 3))          ; does not work

(apply #'foo<-list '(1 2 3) nil)        ; does work

Here is the backtrace:

Debugger entered--Lisp error: (wrong-number-of-arguments foo<-list--cmacro 2)
  signal(wrong-number-of-arguments (foo<-list--cmacro 2))
  (if (= (length --cl-rest--) 3) (pop --cl-rest--) (signal 'wrong-number-of-arguments (list 'foo<-list--cmacro (length --cl-rest--))))
  (let* ((--cl-rest-- (if (= (length --cl-rest--) 1) (car --cl-rest--) (signal 'wrong-number-of-arguments (list 'foo<-list--cmacro (length --cl-rest--))))) (bar (if (= (length --cl-rest--) 3) (pop --cl-rest--) (signal 'wrong-number-of-arguments (list 'foo<-list--cmacro (length --cl-rest--))))) (_ (pop --cl-rest--)) (baz (car --cl-rest--))) (cl-block foo<-list--cmacro (cl--defsubst-expand '(bar _ baz) '(cl-block foo<-list (record 'foo bar baz)) nil nil nil bar _ baz)))
  foo<-list--cmacro((foo<-list '(1 2 3)) '(1 2 3))
  apply(foo<-list--cmacro (foo<-list '(1 2 3)) '(1 2 3))
  macroexp--compiler-macro(foo<-list--cmacro (foo<-list '(1 2 3)))
  #f(compiled-function (form func) #<bytecode -0x1ed89cfba17e95bb>)(((foo<-list '(1 2 3))) foo<-list)
  macroexp--expand-all((foo<-list '(1 2 3)))
  macroexp--all-forms((progn (foo<-list '(1 2 3))) 1)
  #f(compiled-function (form func) #<bytecode -0x1ed89cfba17e95bb>)(((progn (foo<-list '(1 2 3)))) progn)
  macroexp--expand-all((progn (foo<-list '(1 2 3))))
  macroexpand-all((progn (foo<-list '(1 2 3))))
  elisp--eval-last-sexp(nil)
  eval-last-sexp(nil)
  funcall-interactively(eval-last-sexp nil)
  call-interactively(eval-last-sexp nil nil)
  command-execute(eval-last-sexp)

Affected versions:

GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.24, cairo version 1.16.0)

GNU Emacs 28.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.33, cairo version 1.17.6) of 2022-04-28

bug#55355: TBD: inappropriate inlining, cmacro errors

[Lars Ingebrigtsen]

(What does "TBD" mean here?  To be decided?)

Ivan Sokolov <ivan-p-sokolov@ya.ru> writes:

> Hi all! I encountered inlining errors, unfortunately I have no idea what
> is causing them.
>
> Here is the code:
>
> (cl-defstruct (foo (:constructor foo<-list ((bar _ baz))))
>   bar
>   baz)
>
> (foo<-list '(1 2 3))                    ; does not work
>
> (funcall #'foo<-list '(1 2 3))          ; does not work
>
> (apply #'foo<-list '(1 2 3) nil)        ; does work
>
> Here is the backtrace:
>
> Debugger entered--Lisp error: (wrong-number-of-arguments foo<-list--cmacro 2)
>   signal(wrong-number-of-arguments (foo<-list--cmacro 2))

Perhaps Stefan has some comments; added to the CCs.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#55355: TBD: inappropriate inlining, cmacro errors

[Ivan Sokolov]

On May 11, 2022 12:10:44 PM UTC, Lars Ingebrigtsen <larsi@gnus.org> wrote:
>(What does "TBD" mean here?  To be decided?)

Yeah, to be discussed or decided, I am sure there are a better name for the issue.

I asked my friends to test the code and they had even more interesting results:

(foo<-list (1 2 3)) ; works, no quote

(funcall #'foo<-list (1 2 3)) ; works, no quote

Version:
GNU Emacs 29.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.30, cairo version 1.16.0)
Commit: 734f0f68a492f999a307e1cfa6f1cd7df408333f

bug#55355: TBD: inappropriate inlining, cmacro errors

[Eli Zaretskii]

> Cc: 55355@debbugs.gnu.org, Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Wed, 11 May 2022 18:20:41 +0000
> From: Ivan Sokolov <ivan-p-sokolov@ya.ru>
> 
> On May 11, 2022 12:10:44 PM UTC, Lars Ingebrigtsen <larsi@gnus.org> wrote:
> >(What does "TBD" mean here?  To be decided?)
> 
> Yeah, to be discussed or decided, I am sure there are a better name for the issue.

To Be Determined.

bug#55355: TBD: inappropriate inlining, cmacro errors

[Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors]

>> (cl-defstruct (foo (:constructor foo<-list ((bar _ baz))))
>>   bar
>>   baz)
[...]
> Perhaps Stefan has some comments; added to the CCs.

Looks like another bug in `cl-defsubst`.

To the extent that I dislike this "destructuring args" in function
signatures, I'd recommend "if it hurts, don't do that".

You can probably work around the problem using the `:noinline` feature
added recently to `cl-defstruct`.  As for a fix, it's probably a small
matter of making `cl-defsubst` give up on inlining when the formal
arglist is "too complex".


        Stefan