bug#16416: 24.3; [SMIE] Assertion failure in smie-prec2->grammar

[cauderlier@crans.org (Raphaël Cauderlier)]

Hello,

I started emacs with emacs -Q and evaled the following file with
load-file:

-----
(require 'smie)
(smie-prec2->grammar (smie-bnf->prec2 '((name) (l ("a" name)))))
-----

This raised the following error message:

(cl-assertion-failed (numberp (car cons)))

where I expected a SMIE grammar to be returned without error message.
The inner function smie-bnf->prec2 doesn't fail and the documentation
string for the outter function smie-prec2->grammar indicates that it's
argument could be a value returned by smie-bnf->prec2:

-----
smie-prec2->grammar is a compiled Lisp function in `smie.el'.

(smie-prec2->grammar PREC2)

Take a 2D precedence table and turn it into an alist of precedence levels.
PREC2 is a table as returned by `smie-precs->prec2' or
`smie-bnf->prec2'.
-----

I hope I gave you enough information to reproduce this issue.  I'm not
very familiar with the Lisp Debugger so I don't know how to get a
backtrace from a cl-assertion-failed.

Have a nice day!

-- 
Raphaël Cauderlier



In GNU Emacs 24.3.1 (x86_64-pc-linux-gnu, GTK+ Version 3.8.6)
 of 2013-12-22 on brahms, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11204000
System Description:	Debian GNU/Linux testing (jessie)

Configured using:
 `configure '--build' 'x86_64-linux-gnu' '--build' 'x86_64-linux-gnu'
 '--prefix=/usr' '--sharedstatedir=/var/lib' '--libexecdir=/usr/lib'
 '--localstatedir=/var/lib' '--infodir=/usr/share/info'
 '--mandir=/usr/share/man' '--with-pop=yes'
 '--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.3/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.3/site-lisp:/usr/share/emacs/site-lisp'
 '--with-crt-dir=/usr/lib/x86_64-linux-gnu' '--with-x=yes'
 '--with-x-toolkit=gtk3' '--with-toolkit-scroll-bars'
 'build_alias=x86_64-linux-gnu' 'CFLAGS=-g -O2 -fstack-protector
 --param=ssp-buffer-size=4 -Wformat -Werror=format-security -Wall'
 'LDFLAGS=-Wl,-z,relro' 'CPPFLAGS=-D_FORTIFY_SOURCE=2''

Important settings:
  value of $LANG: fr_FR.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x l o a d - f i l e <return> s m i e - b u g . l 
<backspace> e l <return> M-x r e p o r t - e m a c 
s - b u g <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Loading /home/harry/test/smie-bug.el (source)...
smie-prec2->grammar: Assertion failed: (numberp (car cons))

Load-path shadows:
None found.

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