From b51d6c92fd5567e37d43f4ccd9a575c48d9ebbb3 Mon Sep 17 00:00:00 2001
From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Fri, 16 Nov 2007 22:16:01 +0000
Subject: (Fset_match_data): Remove the `evaporate' feature.
(unwind_set_match_data): Don't use the `evaporate' feature.
---
src/search.c | 28 +++++++++++++---------------
1 file changed, 13 insertions(+), 15 deletions(-)
(limited to 'src/search.c')
diff --git a/src/search.c b/src/search.c
index 3a9fabeb3ce..ad4fbc45469 100644
--- a/src/search.c
+++ b/src/search.c
@@ -2892,11 +2892,15 @@ Return value is undefined if the last search failed. */)
return reuse;
}
-/* Internal usage only:
- If RESEAT is `evaporate', put the markers back on the free list
- immediately. No other references to the markers must exist in this case,
- so it is used only internally on the unwind stack and save-match-data from
- Lisp. */
+/* We used to have an internal use variant of `reseat' described as:
+
+ If RESEAT is `evaporate', put the markers back on the free list
+ immediately. No other references to the markers must exist in this
+ case, so it is used only internally on the unwind stack and
+ save-match-data from Lisp.
+
+ But it was ill-conceived: those supposedly-internal markers get exposed via
+ the undo-list, so freeing them here is unsafe. */
DEFUN ("set-match-data", Fset_match_data, Sset_match_data, 1, 2, 0,
doc: /* Set internal data on last search match from elements of LIST.
@@ -2981,10 +2985,7 @@ If optional arg RESEAT is non-nil, make markers on LIST point nowhere. */)
if (!NILP (reseat) && MARKERP (m))
{
- if (EQ (reseat, Qevaporate))
- free_marker (m);
- else
- unchain_marker (XMARKER (m));
+ unchain_marker (XMARKER (m));
XSETCAR (list, Qnil);
}
@@ -3002,10 +3003,7 @@ If optional arg RESEAT is non-nil, make markers on LIST point nowhere. */)
if (!NILP (reseat) && MARKERP (m))
{
- if (EQ (reseat, Qevaporate))
- free_marker (m);
- else
- unchain_marker (XMARKER (m));
+ unchain_marker (XMARKER (m));
XSETCAR (list, Qnil);
}
}
@@ -3069,8 +3067,8 @@ static Lisp_Object
unwind_set_match_data (list)
Lisp_Object list;
{
- /* It is safe to free (evaporate) the markers immediately. */
- return Fset_match_data (list, Qevaporate);
+ /* It is NOT ALWAYS safe to free (evaporate) the markers immediately. */
+ return Fset_match_data (list, Qt);
}
/* Called to unwind protect the match data. */
--
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