(display_mode_element): Detect cycles.

This commit is contained in:
Andreas Schwab 2009-09-11 16:46:08 +00:00
parent 7e0aa125bc
commit 78012bd2ec
2 changed files with 13 additions and 7 deletions

View file

@ -1,3 +1,7 @@
2009-09-11 Andreas Schwab <schwab@linux-m68k.org>
* xdisp.c (display_mode_element): Detect cycles.
2009-09-11 Stefan Monnier <monnier@iro.umontreal.ca>
* keymap.c (where_is_internal): Don't erroneously return nil right after

View file

@ -17750,14 +17750,10 @@ display_mode_element (it, depth, field_width, precision, elt, props, risky)
}
else if (STRINGP (car) || CONSP (car))
{
register int limit = 5000;
/* Limit is to protect against circular lists.
The limit used to be 50, but if you use enough minor modes,
minor-mode-alist will easily grow past 50. Circular lists
are rather unlikely, so it's better for the limit to be
"too large" rather than "too small". */
Lisp_Object halftail = elt;
int len = 0;
while (CONSP (elt)
&& --limit > 0
&& (precision <= 0 || n < precision))
{
n += display_mode_element (it, depth,
@ -17769,6 +17765,12 @@ display_mode_element (it, depth, field_width, precision, elt, props, risky)
precision - n, XCAR (elt),
props, risky);
elt = XCDR (elt);
len++;
if ((len & 1) == 0)
halftail = XCDR (halftail);
/* Check for cycle. */
if (EQ (halftail, elt))
break;
}
}
}