bug#64876: 30.0.50; byte-compiler warning

bug#64876: 30.0.50; byte-compiler warning

[Richard Copley]

Evaluating the form "(byte-compile '(= (point)))" gives the
warning "reference to free variable ‘form’", starting from this
commit:

  e55855c5a1e85e230d2860c973358a34eb72da64
  Commit:     Mattias Engdegård <mattiase@acm.org>
  CommitDate: Sun Jan 29 12:02:57 2023 +0100
  Better compilation of n-ary comparisons

Is there a missing comma in "`(progn (cadr form) t))" in
byte-opt--nary-comparison in the case of 1 argument?

In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, cairo version
 1.16.0) of 2023-07-26 built on machine
Repository revision: 04a930a08ce80d8dcc123f86a3f153f23ec31a29
Repository branch: master
System Description: Ubuntu 22.04.1 LTS

Configured using:
 'configure --with-x-toolkit=no --with-xpm=ifavailable
 --with-jpeg=ifavailable --with-gif=ifavailable --with-tiff=ifavailable'

Configured features:
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MODULES NOTIFY INOTIFY OLDXMENU PDUMPER PNG SECCOMP SOUND SQLITE3
THREADS X11 XDBE XIM ZLIB

Important settings:
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  locale-coding-system: utf-8-unix

Major mode: Fundamental

Minor modes in effect:
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  global-font-lock-mode: t
  blink-cursor-mode: t
  buffer-read-only: t
  line-number-mode: t
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  auto-compression-mode: t

Load-path shadows:
None found.

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Memory information:
((conses 16 47432 9576) (symbols 48 5869 0) (strings 32 14970 1832)
 (string-bytes 1 423597) (vectors 16 8368)
 (vector-slots 8 105904 7199) (floats 8 24 9048) (intervals 56 256 5)
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bug#64876: 30.0.50; byte-compiler warning

[Mattias Engdegård]

26 juli 2023 kl. 18.11 skrev Richard Copley <rcopley@gmail.com>:

> Evaluating the form "(byte-compile '(= (point)))" gives the
> warning "reference to free variable ‘form’"

Oops, sorry about that; should be fixed now. Thanks for the report!

A warning about backquote forms without any unquoting would have helped here, but a quick test resulted in hundreds of false positives and little else so it's probably not practical at this point.

A less lazy programmer who would include a test case with the original change would have helped, too.

bug#64876: 30.0.50; byte-compiler warning

[Mattias Engdegård]

Closing.