Revision: 1719
http://vcs.pcre.org/viewvc?view=rev&revision=1719
Author: ph10
Date: 2017-12-12 15:07:18 +0000 (Tue, 12 Dec 2017)
Log Message:
-----------
Fix wrong first character when a backreference with a zero repeat is first
(apart from assersions) in a pattern.
Modified Paths:
--------------
code/trunk/ChangeLog
code/trunk/pcre_compile.c
code/trunk/testdata/testinput2
code/trunk/testdata/testoutput2
Modified: code/trunk/ChangeLog
===================================================================
--- code/trunk/ChangeLog 2017-12-08 14:09:22 UTC (rev 1718)
+++ code/trunk/ChangeLog 2017-12-12 15:07:18 UTC (rev 1719)
@@ -31,7 +31,12 @@
lines were processed (assuming 32-bit ints). They have all been changed to
unsigned long ints.
+7. If a backreference with a minimum repeat count of zero was first in a
+pattern, apart from assertions, an incorrect first matching character could be
+recorded. For example, for the pattern /(?=(a))\1?b/, "b" was incorrectly set
+as the first character of a match.
+
Version 8.41 05-July-2017
-------------------------
Modified: code/trunk/pcre_compile.c
===================================================================
--- code/trunk/pcre_compile.c 2017-12-08 14:09:22 UTC (rev 1718)
+++ code/trunk/pcre_compile.c 2017-12-12 15:07:18 UTC (rev 1719)
@@ -8060,7 +8060,7 @@
single group (i.e. not to a duplicated name. */
HANDLE_REFERENCE:
- if (firstcharflags == REQ_UNSET) firstcharflags = REQ_NONE;
+ if (firstcharflags == REQ_UNSET) zerofirstcharflags = firstcharflags = REQ_NONE;
previous = code;
item_hwm_offset = cd->hwm - cd->start_workspace;
*code++ = ((options & PCRE_CASELESS) != 0)? OP_REFI : OP_REF;
Modified: code/trunk/testdata/testinput2
===================================================================
--- code/trunk/testdata/testinput2 2017-12-08 14:09:22 UTC (rev 1718)
+++ code/trunk/testdata/testinput2 2017-12-12 15:07:18 UTC (rev 1719)
@@ -4249,4 +4249,12 @@
/(?=.*[A-Z])/I
+"(?<=(a))\1?b"
+ ab
+ aaab
+
+"(?=(a))\1?b"
+ ab
+ aaab
+
/-- End of testinput2 --/
Modified: code/trunk/testdata/testoutput2
===================================================================
--- code/trunk/testdata/testoutput2 2017-12-08 14:09:22 UTC (rev 1718)
+++ code/trunk/testdata/testoutput2 2017-12-12 15:07:18 UTC (rev 1719)
@@ -14705,4 +14705,20 @@
No first char
No need char
+"(?<=(a))\1?b"
+ ab
+ 0: b
+ 1: a
+ aaab
+ 0: ab
+ 1: a
+
+"(?=(a))\1?b"
+ ab
+ 0: ab
+ 1: a
+ aaab
+ 0: ab
+ 1: a
+
/-- End of testinput2 --/
