Re: Lisp reader bug

[Andreas Schwab <schwab@suse.de>]

storm@cua.dk (Kim F. Storm) writes:

|> Kenichi Handa <handa@m17n.org> writes:
|> 
|> > Emacs of CVS HEAD has a bug in Lisp reader.  For instance,
|> > 
|> > (read (format "'%c" (decode-char 'ucs #x102)))
|> > => (quote )
|> > 
|> > I'm not sure, but perhaps this change is the cause.
|> > 
|> > 2003-02-18  Kim F. Storm  <storm@cua.dk>
|> > 
|> > 	* lread.c (read1): Fix last change.
|> > 	"`" is not always special.  Allow "?" after a character constant.
|> > 
|> > This change adds codes something like this (total 4 places):
|> > 
|> > 	  || index ("\"';([#?", next_next_char)
|> > 
|> > but, it seems that `index' doesn't work well if the second
|> > arg is greater than 0xFF.  Actually, if I change such lines
|> > to:
|> > 
|> > 	  || (next_next_char < 0x100 && index ("\"';([#?", next_next_char))
|> > 
|> > the bug disappears.
|> > 
|> > Kim, could you take a look at this problem?
|> 
|> I'm not aware of that limitation in `index' (it is not documented),

The POSIX standard says that index shall be equivalen to strchr, and the C
standard says that strchr converts its second argument to char before the
comparison.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux AG, Deutschherrnstr. 15-19, D-90429 Nürnberg
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