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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.3 05-Jul-07  Version 7.9 xx-xxx-09
5    ---------------------
6    
7    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
8        (pcretest), all targets were linked against these libraries. This included
9        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
10        libraries. This caused unwanted dependencies to be created. This problem
11        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
12        pcretest is linked with readline.
13    
14    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
15        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
16        moved outside it again, because FALSE and TRUE are already defined in AIX,
17        but BOOL is not.
18    
19    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
20        PCRE_MATCH_LIMIT_RETURSION values as ints, when they should be long ints.
21    
22    4.  The pcregrep documentation said spaces were inserted as well as colons (or
23        hyphens) following file names and line numbers when outputting matching
24        lines. This is not true; no spaces are inserted. I have also clarified the
25        wording for the --colour (or --color) option.
26    
27    5.  When --colour was used with -o, the list of matching strings was not
28        coloured; this is different to GNU grep, so I have changed it to be the
29        same.
30    
31    
32    Version 7.8 05-Sep-08
33    ---------------------
34    
35    1.  Replaced UCP searching code with optimized version as implemented for Ad
36        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
37        stage table and inline lookup instead of a function, giving speed ups of 2
38        to 5 times on some simple patterns that I tested. Permission was given to
39        distribute the MultiStage2.py script that generates the tables (it's not in
40        the tarball, but is in the Subversion repository).
41    
42    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
43        scripts.
44    
45    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
46        a group with a zero qualifier. The result of the study could be incorrect,
47        or the function might crash, depending on the pattern.
48    
49    4.  Caseless matching was not working for non-ASCII characters in back
50        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
51        It now works when Unicode Property Support is available.
52    
53    5.  In pcretest, an escape such as \x{de} in the data was always generating
54        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
55        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
56        truncation.
57    
58    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
59    
60    7.  Added two (int) casts to pcregrep when printing the difference of two
61        pointers, in case they are 64-bit values.
62    
63    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
64        test 2 if it fails.
65    
66    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
67        and a #define of that name to empty if it is not externally set. This is to
68        allow users of MSVC to set it if necessary.
69    
70    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
71        the convenience functions in the pcre_get.c source file.
72    
73    11. An option change at the start of a pattern that had top-level alternatives
74        could cause overwriting and/or a crash. This command provoked a crash in
75        some environments:
76    
77          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
78    
79        This potential security problem was recorded as CVE-2008-2371.
80    
81    12. For a pattern where the match had to start at the beginning or immediately
82        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
83        pcre_dfa_exec() could read past the end of the passed subject if there was
84        no match. To help with detecting such bugs (e.g. with valgrind), I modified
85        pcretest so that it places the subject at the end of its malloc-ed buffer.
86    
87    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
88        exec() might read past the end of the data buffer in UTF-8 mode.
89    
90    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
91        the data contained the byte 0x85 as part of a UTF-8 character within its
92        first line. This applied both to normal and DFA matching.
93    
94    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
95        /^[^d]*?$/8 failed to match "abc".
96    
97    16. Added a missing copyright notice to pcrecpp_internal.h.
98    
99    17. Make it more clear in the documentation that values returned from
100        pcre_exec() in ovector are byte offsets, not character counts.
101    
102    18. Tidied a few places to stop certain compilers from issuing warnings.
103    
104    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
105        supplied by Stefan Weber. I made a further small update for 7.8 because
106        there is a change of source arrangements: the pcre_searchfuncs.c module is
107        replaced by pcre_ucd.c.
108    
109    
110    Version 7.7 07-May-08
111    ---------------------
112    
113    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
114        a string to a long long, pretend we don't even have a long long." This is
115        done by checking for the strtoq, strtoll, and _strtoi64 functions.
116    
117    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
118        pre-7.6 versions, which defined a global no_arg variable instead of putting
119        it in the RE class. (See also #8 below.)
120    
121    3.  Remove a line of dead code, identified by coverity and reported by Nuno
122        Lopes.
123    
124    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
125    
126        (1) The include/exclude patterns were being applied to the whole pathnames
127            of files, instead of just to the final components.
128    
129        (2) If there was more than one level of directory, the subdirectories were
130            skipped unless they satisfied the include/exclude conditions. This is
131            inconsistent with GNU grep (and could even be seen as contrary to the
132            pcregrep specification - which I improved to make it absolutely clear).
133            The action now is always to scan all levels of directory, and just
134            apply the include/exclude patterns to regular files.
135    
136    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
137        --exclude_dir in the tests to avoid scanning .svn directories.
138    
139    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
140        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
141        doesn't support NULs in patterns.
142    
143    7.  Added some missing "const"s to declarations of static tables in
144        pcre_compile.c and pcre_dfa_exec.c.
145    
146    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
147        caused by fix #2  above. (Subsequently also a second patch to fix the
148        first patch. And a third patch - this was a messy problem.)
149    
150    9.  Applied Craig's patch to remove the use of push_back().
151    
152    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
153        matching function regexec().
154    
155    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
156        which, however, unlike Perl's \g{...}, are subroutine calls, not back
157        references. PCRE supports relative numbers with this syntax (I don't think
158        Oniguruma does).
159    
160    12. Previously, a group with a zero repeat such as (...){0} was completely
161        omitted from the compiled regex. However, this means that if the group
162        was called as a subroutine from elsewhere in the pattern, things went wrong
163        (an internal error was given). Such groups are now left in the compiled
164        pattern, with a new opcode that causes them to be skipped at execution
165        time.
166    
167    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
168        to the way PCRE behaves:
169    
170        (a) A lone ] character is dis-allowed (Perl treats it as data).
171    
172        (b) A back reference to an unmatched subpattern matches an empty string
173            (Perl fails the current match path).
174    
175        (c) A data ] in a character class must be notated as \] because if the
176            first data character in a class is ], it defines an empty class. (In
177            Perl it is not possible to have an empty class.) The empty class []
178            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
179            The negative empty class [^] matches any one character, independently
180            of the DOTALL setting.
181    
182    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
183        non-existent subpattern following a character class starting with ']' and
184        containing () gave an internal compiling error instead of "reference to
185        non-existent subpattern". Fortunately, when the pattern did exist, the
186        compiled code was correct. (When scanning forwards to check for the
187        existencd of the subpattern, it was treating the data ']' as terminating
188        the class, so got the count wrong. When actually compiling, the reference
189        was subsequently set up correctly.)
190    
191    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
192        it was being rejected as not supported by pcre_dfa_exec(), even though
193        other assertions are supported. I have made pcre_dfa_exec() support
194        (*FAIL).
195    
196    16. The implementation of 13c above involved the invention of a new opcode,
197        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
198        cannot be changed at match time, I realized I could make a small
199        improvement to matching performance by compiling OP_ALLANY instead of
200        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
201        on the OP_ANY path.
202    
203    17. Compiling pcretest on Windows with readline support failed without the
204        following two fixes: (1) Make the unistd.h include conditional on
205        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
206    
207    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
208        ncurses library to be included for pcretest when ReadLine support is
209        requested, but also to allow for it to be overridden. This patch came from
210        Daniel Bergström.
211    
212    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
213        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
214        any errors with the current Unicode tables. Thanks to Peter Kankowski for
215        spotting this.
216    
217    
218    Version 7.6 28-Jan-08
219    ---------------------
220    
221    1.  A character class containing a very large number of characters with
222        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
223        overflow.
224    
225    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
226        HAVE_LONG_LONG is not defined.
227    
228    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
229        bring them up to date and include new features. This patch includes:
230    
231        - Fixed PH's badly added libz and libbz2 support.
232        - Fixed a problem with static linking.
233        - Added pcredemo. [But later removed - see 7 below.]
234        - Fixed dftables problem and added an option.
235        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
236            HAVE_LONG_LONG.
237        - Added readline support for pcretest.
238        - Added an listing of the option settings after cmake has run.
239    
240    4.  A user submitted a patch to Makefile that makes it easy to create
241        "pcre.dll" under mingw when using Configure/Make. I added stuff to
242        Makefile.am that cause it to include this special target, without
243        affecting anything else. Note that the same mingw target plus all
244        the other distribution libraries and programs are now supported
245        when configuring with CMake (see 6 below) instead of with
246        Configure/Make.
247    
248    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
249        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
250        exported in the Windows port". It has not yet been confirmed that the patch
251        solves the problem, but it does no harm.
252    
253    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
254        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
255        with CMake, and also correct the comment about stack recursion.
256    
257    7.  Remove the automatic building of pcredemo from the ./configure system and
258        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
259        of a program that users should build themselves after PCRE is installed, so
260        building it automatically is not really right. What is more, it gave
261        trouble in some build environments.
262    
263    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
264    
265    
266    Version 7.5 10-Jan-08
267    ---------------------
268    
269    1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
270        values in parens when parsing an RE using the C++ wrapper."
271    
272    2.  Negative specials like \S did not work in character classes in UTF-8 mode.
273        Characters greater than 255 were excluded from the class instead of being
274        included.
275    
276    3.  The same bug as (2) above applied to negated POSIX classes such as
277        [:^space:].
278    
279    4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
280        defined or documented. It seems to have been a typo for PCRE_STATIC, so
281        I have changed it.
282    
283    5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
284        first named subpattern) and a construct such as (?&a) would reference the
285        first named subpattern whose name started with "a" (in other words, the
286        length check was missing). Both these problems are fixed. "Subpattern name
287        expected" is now given for (?&) (a zero-length name), and this patch also
288        makes it give the same error for \k'' (previously it complained that that
289        was a reference to a non-existent subpattern).
290    
291    6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
292        this is right because (?- can be followed by option settings as well as by
293        digits. I have, however, made the messages clearer.
294    
295    7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
296        than the number used in the conditional) now cause a compile-time error.
297        This is actually not compatible with Perl, which accepts such patterns, but
298        treats the conditional as always being FALSE (as PCRE used to), but it
299        seems to me that giving a diagnostic is better.
300    
301    8.  Change "alphameric" to the more common word "alphanumeric" in comments
302        and messages.
303    
304    9.  Fix two occurrences of "backslash" in comments that should have been
305        "backspace".
306    
307    10. Remove two redundant lines of code that can never be obeyed (their function
308        was moved elsewhere).
309    
310    11. The program that makes PCRE's Unicode character property table had a bug
311        which caused it to generate incorrect table entries for sequences of
312        characters that have the same character type, but are in different scripts.
313        It amalgamated them into a single range, with the script of the first of
314        them. In other words, some characters were in the wrong script. There were
315        thirteen such cases, affecting characters in the following ranges:
316    
317          U+002b0 - U+002c1
318          U+0060c - U+0060d
319          U+0061e - U+00612
320          U+0064b - U+0065e
321          U+0074d - U+0076d
322          U+01800 - U+01805
323          U+01d00 - U+01d77
324          U+01d9b - U+01dbf
325          U+0200b - U+0200f
326          U+030fc - U+030fe
327          U+03260 - U+0327f
328          U+0fb46 - U+0fbb1
329          U+10450 - U+1049d
330    
331    12. The -o option (show only the matching part of a line) for pcregrep was not
332        compatible with GNU grep in that, if there was more than one match in a
333        line, it showed only the first of them. It now behaves in the same way as
334        GNU grep.
335    
336    13. If the -o and -v options were combined for pcregrep, it printed a blank
337        line for every non-matching line. GNU grep prints nothing, and pcregrep now
338        does the same. The return code can be used to tell if there were any
339        non-matching lines.
340    
341    14. Added --file-offsets and --line-offsets to pcregrep.
342    
343    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
344        infinitely looping recursion. The bug was that positive lookaheads were not
345        being skipped when checking for a possible empty match (negative lookaheads
346        and both kinds of lookbehind were skipped).
347    
348    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
349        inclusion of <windows.h> to before rather than after the definition of
350        INVALID_FILE_ATTRIBUTES (patch from David Byron).
351    
352    17. Specifying a possessive quantifier with a specific limit for a Unicode
353        character property caused pcre_compile() to compile bad code, which led at
354        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
355        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
356        caused the error; without that there was no problem.
357    
358    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
359    
360    19. Added --enable-pcretest-libreadline.
361    
362    20. In pcrecpp.cc, the variable 'count' was incremented twice in
363        RE::GlobalReplace(). As a result, the number of replacements returned was
364        double what it should be. I removed one of the increments, but Craig sent a
365        later patch that removed the other one (the right fix) and added unit tests
366        that check the return values (which was not done before).
367    
368    21. Several CMake things:
369    
370        (1) Arranged that, when cmake is used on Unix, the libraries end up with
371            the names libpcre and libpcreposix, not just pcre and pcreposix.
372    
373        (2) The above change means that pcretest and pcregrep are now correctly
374            linked with the newly-built libraries, not previously installed ones.
375    
376        (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
377    
378    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
379        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
380        UTF-8 newline character). The key issue is that the pattern starts .*;
381        this means that the match must be either at the beginning, or after a
382        newline. The bug was in the code for advancing after a failed match and
383        checking that the new position followed a newline. It was not taking
384        account of UTF-8 characters correctly.
385    
386    23. PCRE was behaving differently from Perl in the way it recognized POSIX
387        character classes. PCRE was not treating the sequence [:...:] as a
388        character class unless the ... were all letters. Perl, however, seems to
389        allow any characters between [: and :], though of course it rejects as
390        unknown any "names" that contain non-letters, because all the known class
391        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
392        for example, whereas PCRE did not - it did not recognize a POSIX character
393        class. This seemed a bit dangerous, so the code has been changed to be
394        closer to Perl. The behaviour is not identical to Perl, because PCRE will
395        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
396        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
397        Perl does, and where it didn't before.
398    
399    24. Rewrite so as to remove the single use of %n from pcregrep because in some
400        Windows environments %n is disabled by default.
401    
402    
403    Version 7.4 21-Sep-07
404    ---------------------
405    
406    1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
407        means that a class such as [\s] counted as "explicit reference to CR or
408        LF". That isn't really right - the whole point of the change was to try to
409        help when there was an actual mention of one of the two characters. So now
410        the change happens only if \r or \n (or a literal CR or LF) character is
411        encountered.
412    
413    2.  The 32-bit options word was also used for 6 internal flags, but the numbers
414        of both had grown to the point where there were only 3 bits left.
415        Fortunately, there was spare space in the data structure, and so I have
416        moved the internal flags into a new 16-bit field to free up more option
417        bits.
418    
419    3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
420        but did not set the internal JCHANGED flag - either of these is enough to
421        control the way the "get" function works - but the PCRE_INFO_JCHANGED
422        facility is supposed to tell if (?J) was ever used, so now (?J) at the
423        start sets both bits.
424    
425    4.  Added options (at build time, compile time, exec time) to change \R from
426        matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
427    
428    5.  doc/pcresyntax.html was missing from the distribution.
429    
430    6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
431        compatibility, even though it is no longer used.
432    
433    7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
434        strtoull to pcrecpp.cc to select the available functions in WIN32 when the
435        windows.h file is present (where different names are used). [This was
436        reversed later after testing - see 16 below.]
437    
438    8.  Changed all #include <config.h> to #include "config.h". There were also
439        some further <pcre.h> cases that I changed to "pcre.h".
440    
441    9.  When pcregrep was used with the --colour option, it missed the line ending
442        sequence off the lines that it output.
443    
444    10. It was pointed out to me that arrays of string pointers cause lots of
445        relocations when a shared library is dynamically loaded. A technique of
446        using a single long string with a table of offsets can drastically reduce
447        these. I have refactored PCRE in four places to do this. The result is
448        dramatic:
449    
450          Originally:                          290
451          After changing UCP table:            187
452          After changing error message table:   43
453          After changing table of "verbs"       36
454          After changing table of Posix names   22
455    
456        Thanks to the folks working on Gregex for glib for this insight.
457    
458    11. --disable-stack-for-recursion caused compiling to fail unless -enable-
459        unicode-properties was also set.
460    
461    12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
462    
463    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
464        checked only for CRLF.
465    
466    14. Added casts to pcretest.c to avoid compiler warnings.
467    
468    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
469    
470    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
471        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
472        entirely. This removes changes made in 7 above.
473    
474    17. The CMake files have been updated, and there is now more information about
475        building with CMake in the NON-UNIX-USE document.
476    
477    
478    Version 7.3 28-Aug-07
479  ---------------------  ---------------------
480    
481   1. In the rejigging of the build system that eventually resulted in 7.1, the   1. In the rejigging of the build system that eventually resulted in 7.1, the
# Line 87  Version 7.3 05-Jul-07 Line 561  Version 7.3 05-Jul-07
561  12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack  12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
562      past the start of the subject in the presence of bytes with the top bit      past the start of the subject in the presence of bytes with the top bit
563      set, for example "\x8aBCD".      set, for example "\x8aBCD".
564    
565  13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),  13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
566      (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).      (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
567    
568  14. Optimized (?!) to (*FAIL).  14. Optimized (?!) to (*FAIL).
569    
570    15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
571        This restricts code points to be within the range 0 to 0x10FFFF, excluding
572        the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
573        full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
574        does: it's just the validity check that is more restrictive.
575    
576    16. Inserted checks for integer overflows during escape sequence (backslash)
577        processing, and also fixed erroneous offset values for syntax errors during
578        backslash processing.
579    
580    17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
581        for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
582    
583    18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
584        caused an overrun.
585    
586    19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
587        something other than just ASCII characters) inside a group that had an
588        unlimited repeat caused a loop at compile time (while checking to see
589        whether the group could match an empty string).
590    
591    20. Debugging a pattern containing \p or \P could cause a crash. For example,
592        [\P{Any}] did so. (Error in the code for printing property names.)
593    
594    21. An orphan \E inside a character class could cause a crash.
595    
596    22. A repeated capturing bracket such as (A)? could cause a wild memory
597        reference during compilation.
598    
599    23. There are several functions in pcre_compile() that scan along a compiled
600        expression for various reasons (e.g. to see if it's fixed length for look
601        behind). There were bugs in these functions when a repeated \p or \P was
602        present in the pattern. These operators have additional parameters compared
603        with \d, etc, and these were not being taken into account when moving along
604        the compiled data. Specifically:
605    
606        (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
607            length.
608    
609        (b) An item such as \pL+ within a repeated group could cause crashes or
610            loops.
611    
612        (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
613            "reference to non-existent subpattern" error.
614    
615        (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
616    
617    24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
618        characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
619    
620    25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
621    
622    26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
623        character were causing crashes (broken optimization).
624    
625    27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
626        \p or \P) caused a compile-time loop.
627    
628    28. More problems have arisen in unanchored patterns when CRLF is a valid line
629        break. For example, the unstudied pattern [\r\n]A does not match the string
630        "\r\nA" because change 7.0/46 below moves the current point on by two
631        characters after failing to match at the start. However, the pattern \nA
632        *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
633        the same is true. There doesn't seem any very clean way out of this, but
634        what I have chosen to do makes the common cases work: PCRE now takes note
635        of whether there can be an explicit match for \r or \n anywhere in the
636        pattern, and if so, 7.0/46 no longer applies. As part of this change,
637        there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
638        pattern has explicit CR or LF references.
639    
640    29. Added (*CR) etc for changing newline setting at start of pattern.
641    
642    
643  Version 7.2 19-Jun-07  Version 7.2 19-Jun-07

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