bug#18610: 24.4.50; Specific file causing emacs to segfault upon opening

[Andreas Schwab]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Andreas Schwab <schwab@linux-m68k.org>
>> Cc: Kenichi Handa <handa@gnu.org>,  dmantipov@yandex.ru,  
>> maden.ldm@gmail.com,  18610@debbugs.gnu.org
>> Date: Fri, 03 Oct 2014 17:16:27 +0200
>> 
>> Eli Zaretskii <eliz@gnu.org> writes:
>> 
>> > Btw, there's one more issue that bothers me.  In ONE_MORE_BYTE we have
>> > this:
>> >
>> >     c = *src++;                                            \
>> >     if (multibytep && (c & 0x80))                  \
>> >       {                                                    \
>> >    if ((c & 0xFE) == 0xC0)                         \
>> >      c = ((c & 1) << 6) | *src++;                  \
>> >    else                                            \
>> >      {                                             \
>> >        src--;                                      \
>> >        c = - string_char (src, &src, NULL);        \
>> >        record_conversion_result                    \
>> >          (coding, CODING_RESULT_INVALID_SRC);      \
>> >      }                                             \
>> >       }                                                    \
>> >
>> > If 'src' is a signed type
>> 
>> It never is.
>
> You are right.  But c nevertheless does get assigned a negative value
> when the byte at src is beyond 127, at least according to what GDB
> shows me.

Exactly here:
            c = - string_char (src, &src, NULL);

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."