@error in @cindex

[Akim Demaille]

When putting @error in @cindex, the index, when sectioned with
\initials, is broken:

src/texinfo/test-cases % eof @error-in-index.texi                nostromo Err 1
: -------------------- @error-in-index.texi ----------------------
cat > @error-in-index.texi << \EOF
\input texinfo   @c -*-texinfo-*-
@setfilename error
@settitle error

@defcodeindex ex
@synindex ex cp
@syncodeindex fn cp

@ifnottex
@node Top
@top TITLE
@end ifnottex

@cindex A
@cindex @error{}

@printindex cp

@bye
EOF
: ------------------------------------------------------------
src/texinfo/test-cases % texi2dvi --pdf @error-in-index.texi     nostromo 13:33
This is pdfeTeXk, Version 3.14159-1.10b-2.1 (Web2C 7.4.5)
 file:line:error style messages enabled.
entering extended mode
(/home/akim/src/texinfo/test-cases/@error-in-index.texi{/usr/share/texmf/pdftex
/config/pdftex.cfg} (/usr/local/share/texmf/tex/texinfo.tex
Loading texinfo [version 2004-01-28.14]: Basics, pdf,
(/usr/share/texmf/pdftex/plain/misc/pdfcolor.tex) fonts, page headings,
tables, conditionals, indexing, sectioning, toc, environments, defuns, macros,
cross references, insertions, (/usr/share/texmf/tex/generic/dvips/epsf.tex)
localization, and turning on texinfo input format.) (./@error-in-index.aux)
(./@error-in-index.cps)
Runaway argument?
{\} \entry {\error {}}{1} \initial {A} \entry {A}{1} 
/home/akim/src/texinfo/test-cases/@error-in-index.texi:17: File ended while sca
nning use of \initial
[1] )
(see the transcript file for additional information)
Output written on @error-in-index.pdf (1 page, 775 bytes).
Transcript written on @error-in-index.log.
/home/akim/bin/texi2dvi: pdfetex exited with bad status, quitting.


Here is the guilty index file.  Pay attention to the first \initial.

src/texinfo/test-cases % cat @error-in-index.cps                 nostromo 13:33
\initial {\}
\entry {\error {}}{1}
\initial {A}
\entry {A}{1}