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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.3 20-Aug-07  Version 8.20 23-Sep-2011
5    ------------------------
6    
7    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
8        a POSIX class. After further experiments with Perl, which convinced me that
9        Perl has bugs and confusions, a closing square bracket is no longer allowed
10        in a POSIX name. This bug also affected patterns with classes that started
11        with full stops.
12    
13    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
14        captured substring, but while checking the failing first alternative,
15        substring 1 is temporarily captured. If the output vector supplied to
16        pcre_exec() was not big enough for this capture, the yield of the function
17        was still zero ("insufficient space for captured substrings"). This cannot
18        be totally fixed without adding another stack variable, which seems a lot
19        of expense for a edge case. However, I have improved the situation in cases
20        such as /(a)(b)x|abc/ matched against "abc", where the return code
21        indicates that fewer than the maximum number of slots in the ovector have
22        been set.
23    
24    3.  Related to (2) above: when there are more back references in a pattern than
25        slots in the output vector, pcre_exec() uses temporary memory during
26        matching, and copies in the captures as far as possible afterwards. It was
27        using the entire output vector, but this conflicts with the specification
28        that only 2/3 is used for passing back captured substrings. Now it uses
29        only the first 2/3, for compatibility. This is, of course, another edge
30        case.
31    
32    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
33        main code base, and can be used by building with --enable-jit. When this is
34        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
35        runtime --no-jit option is given.
36    
37    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
38        ovector, the return from the function was zero, implying that there were
39        other matches that did not fit. The correct "exactly full" value is now
40        returned.
41    
42    6.  If a subpattern that was called recursively or as a subroutine contained
43        (*PRUNE) or any other control that caused it to give a non-standard return,
44        invalid errors such as "Error -26 (nested recursion at the same subject
45        position)" or even infinite loops could occur.
46    
47    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
48        computing the minimum length on reaching *ACCEPT, and so ended up with the
49        wrong value of 1 rather than 0. Further investigation indicates that
50        computing a minimum subject length in the presence of *ACCEPT is difficult
51        (think back references, subroutine calls), and so I have changed the code
52        so that no minimum is registered for a pattern that contains *ACCEPT.
53    
54    8.  If (*THEN) was present in the first (true) branch of a conditional group,
55        it was not handled as intended.
56    
57    9.  Replaced RunTest.bat with the much improved version provided by Sheri
58        Pierce.
59    
60    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
61        the first byte in a match must be "a".
62    
63    11. Change 17 for 8.13 increased the recursion depth for patterns like
64        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
65        pattern contains any instances of (*THEN). If it does not, the old
66        optimizations are restored. It would be nice to do this on a per-group
67        basis, but at the moment that is not feasible.
68    
69    
70    Version 8.13 16-Aug-2011
71    ------------------------
72    
73    1.  The Unicode data tables have been updated to Unicode 6.0.0.
74    
75    2.  Two minor typos in pcre_internal.h have been fixed.
76    
77    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
78        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
79        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
80    
81    4.  There were a number of related bugs in the code for matching backrefences
82        caselessly in UTF-8 mode when codes for the characters concerned were
83        different numbers of bytes. For example, U+023A and U+2C65 are an upper
84        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
85        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
86        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
87        2-byte code at the end of the subject (it thought there wasn't enough data
88        left).
89    
90    5.  Comprehensive information about what went wrong is now returned by
91        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
92        as the output vector has at least 2 elements. The offset of the start of
93        the failing character and a reason code are placed in the vector.
94    
95    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
96        now returned is for the first byte of the failing character, instead of the
97        last byte inspected. This is an incompatible change, but I hope it is small
98        enough not to be a problem. It makes the returned offset consistent with
99        pcre_exec() and pcre_dfa_exec().
100    
101    7.  pcretest now gives a text phrase as well as the error number when
102        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
103        failure, the offset and reason code are output.
104    
105    8.  When \R was used with a maximizing quantifier it failed to skip backwards
106        over a \r\n pair if the subsequent match failed. Instead, it just skipped
107        back over a single character (\n). This seems wrong (because it treated the
108        two characters as a single entity when going forwards), conflicts with the
109        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
110        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
111        has been changed.
112    
113    9.  Some internal refactoring has changed the processing so that the handling
114        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
115        time (the PCRE_DOTALL option was changed this way some time ago: version
116        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
117        which was always a bit of a fudge. It also means that there is one less
118        argument for the match() function, which reduces its stack requirements
119        slightly. This change also fixes an incompatibility with Perl: the pattern
120        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
121    
122    10. More internal refactoring has drastically reduced the number of recursive
123        calls to match() for possessively repeated groups such as (abc)++ when
124        using pcre_exec().
125    
126    11. While implementing 10, a number of bugs in the handling of groups were
127        discovered and fixed:
128    
129        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
130        (a|)*(?1) gave a compile-time internal error.
131        ((a|)+)+  did not notice that the outer group could match an empty string.
132        (^a|^)+   was not marked as anchored.
133        (.*a|.*)+ was not marked as matching at start or after a newline.
134    
135    12. Yet more internal refactoring has removed another argument from the match()
136        function. Special calls to this function are now indicated by setting a
137        value in a variable in the "match data" data block.
138    
139    13. Be more explicit in pcre_study() instead of relying on "default" for
140        opcodes that mean there is no starting character; this means that when new
141        ones are added and accidentally left out of pcre_study(), testing should
142        pick them up.
143    
144    14. The -s option of pcretest has been documented for ages as being an old
145        synonym of -m (show memory usage). I have changed it to mean "force study
146        for every regex", that is, assume /S for every regex. This is similar to -i
147        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
148        using it. It makes it easier to run collections of tests with and without
149        study enabled, and thereby test pcre_study() more easily. All the standard
150        tests are now run with and without -s (but some patterns can be marked as
151        "never study" - see 20 below).
152    
153    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
154        restoration of the capturing data to the outer values was not happening
155        correctly.
156    
157    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
158        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
159        pattern had matched an empty string, and so incorrectly returned a no
160        match.
161    
162    17. There was optimizing code for the last branch of non-capturing parentheses,
163        and also for the obeyed branch of a conditional subexpression, which used
164        tail recursion to cut down on stack usage. Unfortunately, now that there is
165        the possibility of (*THEN) occurring in these branches, tail recursion is
166        no longer possible because the return has to be checked for (*THEN). These
167        two optimizations have therefore been removed. [But see 8.20/11 above.]
168    
169    18. If a pattern containing \R was studied, it was assumed that \R always
170        matched two bytes, thus causing the minimum subject length to be
171        incorrectly computed because \R can also match just one byte.
172    
173    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
174        was incorrectly computed.
175    
176    20. If /S is present twice on a test pattern in pcretest input, it now
177        *disables* studying, thereby overriding the use of -s on the command line
178        (see 14 above). This is necessary for one or two tests to keep the output
179        identical in both cases.
180    
181    21. When (*ACCEPT) was used in an assertion that matched an empty string and
182        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
183    
184    22. When an atomic group that contained a capturing parenthesis was
185        successfully matched, but the branch in which it appeared failed, the
186        capturing was not being forgotten if a higher numbered group was later
187        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
188        group 1 to "a", when in fact it should be unset. This applied to multi-
189        branched capturing and non-capturing groups, repeated or not, and also to
190        positive assertions (capturing in negative assertions does not happen
191        in PCRE) and also to nested atomic groups.
192    
193    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
194        subject after a captured substring, to make it easier to tell which of a
195        number of identical substrings has been captured.
196    
197    24. The way atomic groups are processed by pcre_exec() has been changed so that
198        if they are repeated, backtracking one repetition now resets captured
199        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
200        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
201        "aaa". Previously, it would have been "a". As part of this code
202        refactoring, the way recursive calls are handled has also been changed.
203    
204    25. If an assertion condition captured any substrings, they were not passed
205        back unless some other capturing happened later. For example, if
206        (?(?=(a))a) was matched against "a", no capturing was returned.
207    
208    26. When studying a pattern that contained subroutine calls or assertions,
209        the code for finding the minimum length of a possible match was handling
210        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
211        group 1 called group 2 while simultaneously a separate group 2 called group
212        1). A stack overflow occurred in this case. I have fixed this by limiting
213        the recursion depth to 10.
214    
215    27. Updated RunTest.bat in the distribution to the version supplied by Tom
216        Fortmann. This supports explicit test numbers on the command line, and has
217        argument validation and error reporting.
218    
219    28. An instance of \X with an unlimited repeat could fail if at any point the
220        first character it looked at was a mark character.
221    
222    29. Some minor code refactoring concerning Unicode properties and scripts
223        should reduce the stack requirement of match() slightly.
224    
225    30. Added the '=' option to pcretest to check the setting of unused capturing
226        slots at the end of the pattern, which are documented as being -1, but are
227        not included in the return count.
228    
229    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
230        compiled something random. Now it gives a compile-time error (as does
231        Perl).
232    
233    32. A *MARK encountered during the processing of a positive assertion is now
234        recorded and passed back (compatible with Perl).
235    
236    33. If --only-matching or --colour was set on a pcregrep call whose pattern
237        had alternative anchored branches, the search for a second match in a line
238        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
239        matched the line "0102" twice. The same bug affected patterns that started
240        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
241        twice.
242    
243    34. Previously, PCRE did not allow quantification of assertions. However, Perl
244        does, and because of capturing effects, quantifying parenthesized
245        assertions may at times be useful. Quantifiers are now allowed for
246        parenthesized assertions.
247    
248    35. A minor code tidy in pcre_compile() when checking options for \R usage.
249    
250    36. \g was being checked for fancy things in a character class, when it should
251        just be a literal "g".
252    
253    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
254        appearance of a nested POSIX class supersedes an apparent external class.
255        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
256        unescaped square brackets may also appear as part of class names. For
257        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
258        more like Perl. (But see 8.20/1 above.)
259    
260    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
261        was because it thought it was \N{name}, which is not supported).
262    
263    39. Add minix to OS list not supporting the -S option in pcretest.
264    
265    40. PCRE tries to detect cases of infinite recursion at compile time, but it
266        cannot analyze patterns in sufficient detail to catch mutual recursions
267        such as ((?1))((?2)). There is now a runtime test that gives an error if a
268        subgroup is called recursively as a subpattern for a second time at the
269        same position in the subject string. In previous releases this might have
270        been caught by the recursion limit, or it might have run out of stack.
271    
272    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
273        happen only once. PCRE was, however incorrectly giving a compile time error
274        "recursive call could loop indefinitely" because it cannot analyze the
275        pattern in sufficient detail. The compile time test no longer happens when
276        PCRE is compiling a conditional subpattern, but actual runaway loops are
277        now caught at runtime (see 40 above).
278    
279    42. It seems that Perl allows any characters other than a closing parenthesis
280        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
281        has been changed to be the same.
282    
283    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
284        as not to get warnings when autogen.sh is called. Also changed
285        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
286    
287    44. To help people who use pcregrep to scan files containing exceedingly long
288        lines, the following changes have been made:
289    
290        (a) The default value of the buffer size parameter has been increased from
291            8K to 20K. (The actual buffer used is three times this size.)
292    
293        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
294            PCRE is built.
295    
296        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
297            to be set at run time.
298    
299        (d) Numerical values in pcregrep options can be followed by K or M, for
300            example --buffer-size=50K.
301    
302        (e) If a line being scanned overflows pcregrep's buffer, an error is now
303            given and the return code is set to 2.
304    
305    45. Add a pointer to the latest mark to the callout data block.
306    
307    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
308        partial match of an empty string instead of no match. This was specific to
309        the use of ".".
310    
311    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
312        complete match instead of a partial match. This bug was dependent on both
313        the PCRE_UTF8 and PCRE_DOTALL options being set.
314    
315    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
316        starting byte set, because \b was not being ignored.
317    
318    
319    Version 8.12 15-Jan-2011
320    ------------------------
321    
322    1.  Fixed some typos in the markup of the man pages, and wrote a script that
323        checks for such things as part of the documentation building process.
324    
325    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
326        --match-limit and --recursion-limit options (added for 8.11). In
327        particular, this made one of the standard tests fail. (The integer value
328        went into the wrong half of a long int.)
329    
330    3.  If the --colour option was given to pcregrep with -v (invert match), it
331        did strange things, either producing crazy output, or crashing. It should,
332        of course, ignore a request for colour when reporting lines that do not
333        match.
334    
335    4.  Another pcregrep bug caused similar problems if --colour was specified with
336        -M (multiline) and the pattern match finished with a line ending.
337    
338    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
339        matched in multiline mode, the following line was shown as part of the
340        match. This seems wrong, so I have changed it.
341    
342    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
343        the check for further matches in the same line (so they could be coloured)
344        to overrun the end of the current line. If another match was found, it was
345        incorrectly shown (and then shown again when found in the next line).
346    
347    7.  If pcregrep was compiled under Windows, there was a reference to the
348        function pcregrep_exit() before it was defined. I am assuming this was
349        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
350        reported by a user. I've moved the definition above the reference.
351    
352    
353    Version 8.11 10-Dec-2010
354    ------------------------
355    
356    1.  (*THEN) was not working properly if there were untried alternatives prior
357        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
358        backtracked to try for "b" instead of moving to the next alternative branch
359        at the same level (in this case, to look for "c"). The Perl documentation
360        is clear that when (*THEN) is backtracked onto, it goes to the "next
361        alternative in the innermost enclosing group".
362    
363    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
364        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
365        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
366        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
367        (*THEN).
368    
369    3.  If \s appeared in a character class, it removed the VT character from
370        the class, even if it had been included by some previous item, for example
371        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
372        of \s, but is part of the POSIX "space" class.)
373    
374    4.  A partial match never returns an empty string (because you can always
375        match an empty string at the end of the subject); however the checking for
376        an empty string was starting at the "start of match" point. This has been
377        changed to the "earliest inspected character" point, because the returned
378        data for a partial match starts at this character. This means that, for
379        example, /(?<=abc)def/ gives a partial match for the subject "abc"
380        (previously it gave "no match").
381    
382    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
383        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
384        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
385        has an implication that the given string is incomplete (because a partial
386        match is preferred over a full match). For this reason, these items now
387        give a partial match in this situation. [Aside: previously, the one case
388        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
389        match rather than a full match, which was wrong by the old rules, but is
390        now correct.]
391    
392    6.  There was a bug in the handling of #-introduced comments, recognized when
393        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
394        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
395        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
396        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
397        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
398        places in pcre_compile().
399    
400    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
401        comments when looking ahead for named forward references to subpatterns,
402        the only newline sequence it recognized was NL. It now handles newlines
403        according to the set newline convention.
404    
405    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
406        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
407        cater for a lack of strerror(). These oversights have been fixed.
408    
409    9.  Added --match-limit and --recursion-limit to pcregrep.
410    
411    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
412    
413    11. When the -o option was used, pcregrep was setting a return code of 1, even
414        when matches were found, and --line-buffered was not being honoured.
415    
416    12. Added an optional parentheses number to the -o and --only-matching options
417        of pcregrep.
418    
419    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
420        can match an empty string. The code to do it in pcretest and pcredemo
421        needed fixing:
422    
423        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
424            only one byte after an empty string match just before CRLF (this case
425            just got forgotten; "any" and "anycrlf" were OK).
426    
427        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
428            mode when an empty string match preceded an ASCII character followed by
429            a non-ASCII character. (The code for advancing by one character rather
430            than one byte was nonsense.)
431    
432        (c) The pcredemo.c sample program did not have any code at all to handle
433            the cases when CRLF is a valid newline sequence.
434    
435    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
436        as a starting offset was within the subject string. There is now a new
437        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
438        negative or greater than the length of the string. In order to test this,
439        pcretest is extended to allow the setting of negative starting offsets.
440    
441    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
442        starting offset points to the beginning of a UTF-8 character was
443        unnecessarily clumsy. I tidied it up.
444    
445    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
446        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
447    
448    17. Nobody had reported that the --include_dir option, which was added in
449        release 7.7 should have been called --include-dir (hyphen, not underscore)
450        for compatibility with GNU grep. I have changed it to --include-dir, but
451        left --include_dir as an undocumented synonym, and the same for
452        --exclude-dir, though that is not available in GNU grep, at least as of
453        release 2.5.4.
454    
455    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
456        characters from a string of bytes) have been redefined so as not to use
457        loops, in order to improve performance in some environments. At the same
458        time, I abstracted some of the common code into auxiliary macros to save
459        repetition (this should not affect the compiled code).
460    
461    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
462        compile-time error is now given if \c is not followed by an ASCII
463        character, that is, a byte less than 128. (In EBCDIC mode, the code is
464        different, and any byte value is allowed.)
465    
466    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
467        START_OPTIMIZE option, which is now allowed at compile time - but just
468        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
469        to pcregrep and other applications that have no direct access to PCRE
470        options. The new /Y option in pcretest sets this option when calling
471        pcre_compile().
472    
473    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
474        back references. Groups containing recursive back references were forced to
475        be atomic by that change, but in the case of named groups, the amount of
476        memory required was incorrectly computed, leading to "Failed: internal
477        error: code overflow". This has been fixed.
478    
479    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
480        pcretest.c, to avoid build problems in some Borland environments.
481    
482    
483    Version 8.10 25-Jun-2010
484    ------------------------
485    
486    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
487        THEN.
488    
489    2.  (*ACCEPT) was not working when inside an atomic group.
490    
491    3.  Inside a character class, \B is treated as a literal by default, but
492        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
493        causes the error). The code is unchanged, but I tidied the documentation.
494    
495    4.  Inside a character class, PCRE always treated \R and \X as literals,
496        whereas Perl faults them if its -w option is set. I have changed PCRE so
497        that it faults them when PCRE_EXTRA is set.
498    
499    5.  Added support for \N, which always matches any character other than
500        newline. (It is the same as "." when PCRE_DOTALL is not set.)
501    
502    6.  When compiling pcregrep with newer versions of gcc which may have
503        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
504        declared with attribute warn_unused_result" were given. Just casting the
505        result to (void) does not stop the warnings; a more elaborate fudge is
506        needed. I've used a macro to implement this.
507    
508    7.  Minor change to pcretest.c to avoid a compiler warning.
509    
510    8.  Added four artifical Unicode properties to help with an option to make
511        \s etc use properties (see next item). The new properties are: Xan
512        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
513    
514    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
515        use Unicode properties. (*UCP) at the start of a pattern can be used to set
516        this option. Modified pcretest to add /W to test this facility. Added
517        REG_UCP to make it available via the POSIX interface.
518    
519    10. Added --line-buffered to pcregrep.
520    
521    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
522        studied, and the match started with a letter with a code point greater than
523        127 whose first byte was different to the first byte of the other case of
524        the letter, the other case of this starting letter was not recognized
525        (#976).
526    
527    12. If a pattern that was studied started with a repeated Unicode property
528        test, for example, \p{Nd}+, there was the theoretical possibility of
529        setting up an incorrect bitmap of starting bytes, but fortunately it could
530        not have actually happened in practice until change 8 above was made (it
531        added property types that matched character-matching opcodes).
532    
533    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
534        possible starting bytes for non-anchored patterns.
535    
536    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
537        \R, and also a number of cases that involve Unicode properties, both
538        explicit and implicit when PCRE_UCP is set.
539    
540    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
541        input, it could crash or give wrong results if characters with values
542        greater than 0xc0 were present in the subject string. (Detail: it assumed
543        UTF-8 input when processing these items.)
544    
545    16. Added a lot of (int) casts to avoid compiler warnings in systems where
546        size_t is 64-bit (#991).
547    
548    17. Added a check for running out of memory when PCRE is compiled with
549        --disable-stack-for-recursion (#990).
550    
551    18. If the last data line in a file for pcretest does not have a newline on
552        the end, a newline was missing in the output.
553    
554    19. The default pcre_chartables.c file recognizes only ASCII characters (values
555        less than 128) in its various bitmaps. However, there is a facility for
556        generating tables according to the current locale when PCRE is compiled. It
557        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
558        characters, are recognized by isspace() and therefore were getting set in
559        these tables, and indeed these tables seem to approximate to ISO 8859. This
560        caused a problem in UTF-8 mode when pcre_study() was used to create a list
561        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
562        which of course cannot start UTF-8 characters. I have changed the code so
563        that only real ASCII characters (less than 128) and the correct starting
564        bytes for UTF-8 encodings are set for characters greater than 127 when in
565        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
566        altogether.)
567    
568    20. Added the /T option to pcretest so as to be able to run tests with non-
569        standard character tables, thus making it possible to include the tests
570        used for 19 above in the standard set of tests.
571    
572    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
573        reference to a subpattern the other side of a comment that contains an
574        opening parenthesis caused either an internal compiling error, or a
575        reference to the wrong subpattern.
576    
577    
578    Version 8.02 19-Mar-2010
579    ------------------------
580    
581    1.  The Unicode data tables have been updated to Unicode 5.2.0.
582    
583    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
584        configured.
585    
586    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
587        original author of that file, following a query about its status.
588    
589    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
590        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
591    
592    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
593        quantifier applied to a forward-referencing subroutine call, could compile
594        incorrect code or give the error "internal error: previously-checked
595        referenced subpattern not found".
596    
597    6.  Both MS Visual Studio and Symbian OS have problems with initializing
598        variables to point to external functions. For these systems, therefore,
599        pcre_malloc etc. are now initialized to local functions that call the
600        relevant global functions.
601    
602    7.  There were two entries missing in the vectors called coptable and poptable
603        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
604        I've fixed the data, and added a kludgy way of testing at compile time that
605        the lengths are correct (equal to the number of opcodes).
606    
607    8.  Following on from 7, I added a similar kludge to check the length of the
608        eint vector in pcreposix.c.
609    
610    9.  Error texts for pcre_compile() are held as one long string to avoid too
611        much relocation at load time. To find a text, the string is searched,
612        counting zeros. There was no check for running off the end of the string,
613        which could happen if a new error number was added without updating the
614        string.
615    
616    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
617    
618    11. \K was not working if it appeared in an atomic group or in a group that
619        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
620        \K is "not well defined" if used in an assertion. PCRE now accepts it if
621        the assertion is positive, but not if it is negative.
622    
623    12. Change 11 fortuitously reduced the size of the stack frame used in the
624        "match()" function of pcre_exec.c by one pointer. Forthcoming
625        implementation of support for (*MARK) will need an extra pointer on the
626        stack; I have reserved it now, so that the stack frame size does not
627        decrease.
628    
629    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
630        item in branch that calls a recursion is a subroutine call - as in the
631        second branch in the above example - was incorrectly given the compile-
632        time error "recursive call could loop indefinitely" because pcre_compile()
633        was not correctly checking the subroutine for matching a non-empty string.
634    
635    14. The checks for overrunning compiling workspace could trigger after an
636        overrun had occurred. This is a "should never occur" error, but it can be
637        triggered by pathological patterns such as hundreds of nested parentheses.
638        The checks now trigger 100 bytes before the end of the workspace.
639    
640    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
641    
642    
643    Version 8.01 19-Jan-2010
644    ------------------------
645    
646    1.  If a pattern contained a conditional subpattern with only one branch (in
647        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
648        computed the wrong minimum data length (which is of course zero for such
649        subpatterns). This could cause incorrect "no match" results.
650    
651    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
652        the pattern is reset in the first branch, pcre_compile() failed with
653        "internal error: code overflow at offset...". This happened only when
654        the reset was to the original external option setting. (An optimization
655        abstracts leading options settings into an external setting, which was the
656        cause of this.)
657    
658    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
659        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
660        assertion pattern did not match (meaning that the assertion was true), it
661        was incorrectly treated as false if the SKIP had been reached during the
662        matching. This also applied to assertions used as conditions.
663    
664    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
665        assertion subpattern, including such a pattern used as a condition,
666        unpredictable results occurred, instead of the error return
667        PCRE_ERROR_DFA_UITEM.
668    
669    5.  The C++ GlobalReplace function was not working like Perl for the special
670        situation when an empty string is matched. It now does the fancy magic
671        stuff that is necessary.
672    
673    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
674        removed. (These were left over from very, very early versions of PCRE.)
675    
676    7.  Some cosmetic changes to the code to make life easier when compiling it
677        as part of something else:
678    
679        (a) Change DEBUG to PCRE_DEBUG.
680    
681        (b) In pcre_compile(), rename the member of the "branch_chain" structure
682            called "current" as "current_branch", to prevent a collision with the
683            Linux macro when compiled as a kernel module.
684    
685        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
686            prevent a collision with the Linux macro when compiled as a kernel
687            module.
688    
689    8.  In pcre_compile() there are some checks for integer overflows that used to
690        cast potentially large values to (double). This has been changed to that
691        when building, a check for int64_t is made, and if it is found, it is used
692        instead, thus avoiding the use of floating point arithmetic. (There is no
693        other use of FP in PCRE.) If int64_t is not found, the fallback is to
694        double.
695    
696    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
697        2005 (difference between two addresses compared to an unsigned value).
698    
699    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
700        custom one, because of the following reported problem in Windows:
701    
702          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
703              under Win32.
704          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
705              therefore missing the function definition.
706          - The compiler thus generates a "C" signature for the test function.
707          - The linker fails to find the "C" function.
708          - PCRE fails to configure if asked to do so against libbz2.
709    
710    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
711        messages were output:
712    
713          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
714          rerunning libtoolize, to keep the correct libtool macros in-tree.
715          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
716    
717        I have done both of these things.
718    
719    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
720        most of the time, it *can* run out if it is given a pattern that contains a
721        runaway infinite recursion. I updated the discussion in the pcrestack man
722        page.
723    
724    13. Now that we have gone to the x.xx style of version numbers, the minor
725        version may start with zero. Using 08 or 09 is a bad idea because users
726        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
727        interpreted as invalid octal numbers. I've updated the previous comment in
728        configure.ac, and also added a check that gives an error if 08 or 09 are
729        used.
730    
731    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
732        causing partial matching to fail when the end of the subject matched \W
733        in a UTF-8 pattern where \W was quantified with a minimum of 3.
734    
735    15. There were some discrepancies between the declarations in pcre_internal.h
736        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
737        their definitions. The declarations used "const uschar *" and the
738        definitions used USPTR. Even though USPTR is normally defined as "const
739        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
740        reported that: "This difference in casting confuses some C++ compilers, for
741        example, SunCC recognizes above declarations as different functions and
742        generates broken code for hbpcre." I have changed the declarations to use
743        USPTR.
744    
745    16. GNU libtool is named differently on some systems. The autogen.sh script now
746        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
747        (FreeBSD).
748    
749    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
750        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
751        comment: "Figure out how to create a longlong from a string: strtoll and
752        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
753        instance, but it only takes 2 args instead of 3!"
754    
755    18. A subtle bug concerned with back references has been fixed by a change of
756        specification, with a corresponding code fix. A pattern such as
757        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
758        refers, was giving matches when it shouldn't. For example, xa=xaaa would
759        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
760        same bug. Such groups have to be quantified to be useful, or contained
761        inside another quantified group. (If there's no repetition, the reference
762        can never match.) The problem arises because, having left the group and
763        moved on to the rest of the pattern, a later failure that backtracks into
764        the group uses the captured value from the final iteration of the group
765        rather than the correct earlier one. I have fixed this in PCRE by forcing
766        any group that contains a reference to itself to be an atomic group; that
767        is, there cannot be any backtracking into it once it has completed. This is
768        similar to recursive and subroutine calls.
769    
770    
771    Version 8.00 19-Oct-09
772    ----------------------
773    
774    1.  The table for translating pcre_compile() error codes into POSIX error codes
775        was out-of-date, and there was no check on the pcre_compile() error code
776        being within the table. This could lead to an OK return being given in
777        error.
778    
779    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
780        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
781        in a Windows environment.
782    
783    3.  The pcregrep --count option prints the count for each file even when it is
784        zero, as does GNU grep. However, pcregrep was also printing all files when
785        --files-with-matches was added. Now, when both options are given, it prints
786        counts only for those files that have at least one match. (GNU grep just
787        prints the file name in this circumstance, but including the count seems
788        more useful - otherwise, why use --count?) Also ensured that the
789        combination -clh just lists non-zero counts, with no names.
790    
791    4.  The long form of the pcregrep -F option was incorrectly implemented as
792        --fixed_strings instead of --fixed-strings. This is an incompatible change,
793        but it seems right to fix it, and I didn't think it was worth preserving
794        the old behaviour.
795    
796    5.  The command line items --regex=pattern and --regexp=pattern were not
797        recognized by pcregrep, which required --regex pattern or --regexp pattern
798        (with a space rather than an '='). The man page documented the '=' forms,
799        which are compatible with GNU grep; these now work.
800    
801    6.  No libpcreposix.pc file was created for pkg-config; there was just
802        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
803    
804    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
805        when UCP support is not needed, by modifying the Python script that
806        generates it from Unicode data files. This should not matter if the module
807        is correctly used as a library, but I received one complaint about 50K of
808        unwanted data. My guess is that the person linked everything into his
809        program rather than using a library. Anyway, it does no harm.
810    
811    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
812        was a minimum greater than 1 for a wide character in a possessive
813        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
814        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
815        character. Chaos in the form of incorrect output or a compiling loop could
816        result.
817    
818    9.  The restrictions on what a pattern can contain when partial matching is
819        requested for pcre_exec() have been removed. All patterns can now be
820        partially matched by this function. In addition, if there are at least two
821        slots in the offset vector, the offset of the earliest inspected character
822        for the match and the offset of the end of the subject are set in them when
823        PCRE_ERROR_PARTIAL is returned.
824    
825    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
826        synonymous with PCRE_PARTIAL, for backwards compatibility, and
827        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
828        and may be more useful for multi-segment matching.
829    
830    11. Partial matching with pcre_exec() is now more intuitive. A partial match
831        used to be given if ever the end of the subject was reached; now it is
832        given only if matching could not proceed because another character was
833        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
834        string "Z", which now yields "no match" instead of "partial match". In the
835        case of pcre_dfa_exec(), "no match" is given if every matching path for the
836        final character ended with (*FAIL).
837    
838    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
839        if the pattern had a "must contain" character that was already found in the
840        earlier partial match, unless partial matching was again requested. For
841        example, with the pattern /dog.(body)?/, the "must contain" character is
842        "g". If the first part-match was for the string "dog", restarting with
843        "sbody" failed. This bug has been fixed.
844    
845    13. The string returned by pcre_dfa_exec() after a partial match has been
846        changed so that it starts at the first inspected character rather than the
847        first character of the match. This makes a difference only if the pattern
848        starts with a lookbehind assertion or \b or \B (\K is not supported by
849        pcre_dfa_exec()). It's an incompatible change, but it makes the two
850        matching functions compatible, and I think it's the right thing to do.
851    
852    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
853        so that the demonstration program is easily available in environments where
854        PCRE has not been installed from source.
855    
856    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
857        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
858        library.
859    
860    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
861        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
862        is not the first non-POSIX option to be added. Clearly some people find
863        these options useful.
864    
865    17. If a caller to the POSIX matching function regexec() passes a non-zero
866        value for nmatch with a NULL value for pmatch, the value of
867        nmatch is forced to zero.
868    
869    18. RunGrepTest did not have a test for the availability of the -u option of
870        the diff command, as RunTest does. It now checks in the same way as
871        RunTest, and also checks for the -b option.
872    
873    19. If an odd number of negated classes containing just a single character
874        interposed, within parentheses, between a forward reference to a named
875        subpattern and the definition of the subpattern, compilation crashed with
876        an internal error, complaining that it could not find the referenced
877        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
878        [The bug was that it was starting one character too far in when skipping
879        over the character class, thus treating the ] as data rather than
880        terminating the class. This meant it could skip too much.]
881    
882    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
883        /g option in pcretest when the pattern contains \K, which makes it possible
884        to have an empty string match not at the start, even when the pattern is
885        anchored. Updated pcretest and pcredemo to use this option.
886    
887    21. If the maximum number of capturing subpatterns in a recursion was greater
888        than the maximum at the outer level, the higher number was returned, but
889        with unset values at the outer level. The correct (outer level) value is
890        now given.
891    
892    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
893        PCRE did not set those parentheses (unlike Perl). I have now found a way to
894        make it do so. The string so far is captured, making this feature
895        compatible with Perl.
896    
897    23. The tests have been re-organized, adding tests 11 and 12, to make it
898        possible to check the Perl 5.10 features against Perl 5.10.
899    
900    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
901        pattern matches a fixed length string. PCRE did not allow this; now it
902        does. Neither allows recursion.
903    
904    25. I finally figured out how to implement a request to provide the minimum
905        length of subject string that was needed in order to match a given pattern.
906        (It was back references and recursion that I had previously got hung up
907        on.) This code has now been added to pcre_study(); it finds a lower bound
908        to the length of subject needed. It is not necessarily the greatest lower
909        bound, but using it to avoid searching strings that are too short does give
910        some useful speed-ups. The value is available to calling programs via
911        pcre_fullinfo().
912    
913    26. While implementing 25, I discovered to my embarrassment that pcretest had
914        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
915        study optimizations had never been tested with that matching function.
916        Oops. What is worse, even when it was passed study data, there was a bug in
917        pcre_dfa_exec() that meant it never actually used it. Double oops. There
918        were also very few tests of studied patterns with pcre_dfa_exec().
919    
920    27. If (?| is used to create subpatterns with duplicate numbers, they are now
921        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
922        on the other side of the coin, they are no longer allowed to have different
923        names, because these cannot be distinguished in PCRE, and this has caused
924        confusion. (This is a difference from Perl.)
925    
926    28. When duplicate subpattern names are present (necessarily with different
927        numbers, as required by 27 above), and a test is made by name in a
928        conditional pattern, either for a subpattern having been matched, or for
929        recursion in such a pattern, all the associated numbered subpatterns are
930        tested, and the overall condition is true if the condition is true for any
931        one of them. This is the way Perl works, and is also more like the way
932        testing by number works.
933    
934    
935    Version 7.9 11-Apr-09
936    ---------------------
937    
938    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
939        (pcretest), all targets were linked against these libraries. This included
940        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
941        libraries. This caused unwanted dependencies to be created. This problem
942        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
943        pcretest is linked with readline.
944    
945    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
946        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
947        moved outside it again, because FALSE and TRUE are already defined in AIX,
948        but BOOL is not.
949    
950    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
951        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
952    
953    4.  The pcregrep documentation said spaces were inserted as well as colons (or
954        hyphens) following file names and line numbers when outputting matching
955        lines. This is not true; no spaces are inserted. I have also clarified the
956        wording for the --colour (or --color) option.
957    
958    5.  In pcregrep, when --colour was used with -o, the list of matching strings
959        was not coloured; this is different to GNU grep, so I have changed it to be
960        the same.
961    
962    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
963        each matching line was coloured. Now it goes on to look for further matches
964        of any of the test patterns, which is the same behaviour as GNU grep.
965    
966    7.  A pattern that could match an empty string could cause pcregrep to loop; it
967        doesn't make sense to accept an empty string match in pcregrep, so I have
968        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
969        seems to be how GNU grep behaves.
970    
971    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
972        start or after a newline", because the conditional assertion was not being
973        correctly handled. The rule now is that both the assertion and what follows
974        in the first alternative must satisfy the test.
975    
976    9.  If auto-callout was enabled in a pattern with a conditional group whose
977        condition was an assertion, PCRE could crash during matching, both with
978        pcre_exec() and pcre_dfa_exec().
979    
980    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
981        used for matching.
982    
983    11. Unicode property support in character classes was not working for
984        characters (bytes) greater than 127 when not in UTF-8 mode.
985    
986    12. Added the -M command line option to pcretest.
987    
988    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
989    
990    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
991    
992    16. Added comments and documentation about mis-use of no_arg in the C++
993        wrapper.
994    
995    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
996        from Martin Jerabek that uses macro names for all relevant character and
997        string constants.
998    
999    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1000        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1001        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1002        these, but not everybody uses configure.
1003    
1004    19. A conditional group that had only one branch was not being correctly
1005        recognized as an item that could match an empty string. This meant that an
1006        enclosing group might also not be so recognized, causing infinite looping
1007        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1008        with the subject "ab", where knowledge that the repeated group can match
1009        nothing is needed in order to break the loop.
1010    
1011    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1012        exec(), but without supplying a callout function, matching went wrong.
1013    
1014    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1015        leak if the size of the offset vector was greater than 30. When the vector
1016        is smaller, the saved offsets during recursion go onto a local stack
1017        vector, but for larger vectors malloc() is used. It was failing to free
1018        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1019        error, in fact).
1020    
1021    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1022        heapframe that is used only when UTF-8 support is enabled. This caused no
1023        problem, but was untidy.
1024    
1025    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1026        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1027        included within another project.
1028    
1029    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1030        slightly modified by me:
1031    
1032          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1033              not building pcregrep.
1034    
1035          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1036              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1037    
1038    25. Forward references, both numeric and by name, in patterns that made use of
1039        duplicate group numbers, could behave incorrectly or give incorrect errors,
1040        because when scanning forward to find the reference group, PCRE was not
1041        taking into account the duplicate group numbers. A pattern such as
1042        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1043    
1044    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1045        the feature of a custom pointer more persuasive (as requested by a user).
1046    
1047    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1048        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1049        pre-defined.
1050    
1051    28. Added support for (*UTF8) at the start of a pattern.
1052    
1053    29. Arrange for flags added by the "release type" setting in CMake to be shown
1054        in the configuration summary.
1055    
1056    
1057    Version 7.8 05-Sep-08
1058    ---------------------
1059    
1060    1.  Replaced UCP searching code with optimized version as implemented for Ad
1061        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
1062        stage table and inline lookup instead of a function, giving speed ups of 2
1063        to 5 times on some simple patterns that I tested. Permission was given to
1064        distribute the MultiStage2.py script that generates the tables (it's not in
1065        the tarball, but is in the Subversion repository).
1066    
1067    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
1068        scripts.
1069    
1070    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
1071        a group with a zero qualifier. The result of the study could be incorrect,
1072        or the function might crash, depending on the pattern.
1073    
1074    4.  Caseless matching was not working for non-ASCII characters in back
1075        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
1076        It now works when Unicode Property Support is available.
1077    
1078    5.  In pcretest, an escape such as \x{de} in the data was always generating
1079        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
1080        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
1081        truncation.
1082    
1083    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
1084    
1085    7.  Added two (int) casts to pcregrep when printing the difference of two
1086        pointers, in case they are 64-bit values.
1087    
1088    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
1089        test 2 if it fails.
1090    
1091    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1092        and a #define of that name to empty if it is not externally set. This is to
1093        allow users of MSVC to set it if necessary.
1094    
1095    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1096        the convenience functions in the pcre_get.c source file.
1097    
1098    11. An option change at the start of a pattern that had top-level alternatives
1099        could cause overwriting and/or a crash. This command provoked a crash in
1100        some environments:
1101    
1102          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1103    
1104        This potential security problem was recorded as CVE-2008-2371.
1105    
1106    12. For a pattern where the match had to start at the beginning or immediately
1107        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1108        pcre_dfa_exec() could read past the end of the passed subject if there was
1109        no match. To help with detecting such bugs (e.g. with valgrind), I modified
1110        pcretest so that it places the subject at the end of its malloc-ed buffer.
1111    
1112    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
1113        exec() might read past the end of the data buffer in UTF-8 mode.
1114    
1115    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
1116        the data contained the byte 0x85 as part of a UTF-8 character within its
1117        first line. This applied both to normal and DFA matching.
1118    
1119    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
1120        /^[^d]*?$/8 failed to match "abc".
1121    
1122    16. Added a missing copyright notice to pcrecpp_internal.h.
1123    
1124    17. Make it more clear in the documentation that values returned from
1125        pcre_exec() in ovector are byte offsets, not character counts.
1126    
1127    18. Tidied a few places to stop certain compilers from issuing warnings.
1128    
1129    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
1130        supplied by Stefan Weber. I made a further small update for 7.8 because
1131        there is a change of source arrangements: the pcre_searchfuncs.c module is
1132        replaced by pcre_ucd.c.
1133    
1134    
1135    Version 7.7 07-May-08
1136    ---------------------
1137    
1138    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
1139        a string to a long long, pretend we don't even have a long long." This is
1140        done by checking for the strtoq, strtoll, and _strtoi64 functions.
1141    
1142    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
1143        pre-7.6 versions, which defined a global no_arg variable instead of putting
1144        it in the RE class. (See also #8 below.)
1145    
1146    3.  Remove a line of dead code, identified by coverity and reported by Nuno
1147        Lopes.
1148    
1149    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
1150    
1151        (1) The include/exclude patterns were being applied to the whole pathnames
1152            of files, instead of just to the final components.
1153    
1154        (2) If there was more than one level of directory, the subdirectories were
1155            skipped unless they satisfied the include/exclude conditions. This is
1156            inconsistent with GNU grep (and could even be seen as contrary to the
1157            pcregrep specification - which I improved to make it absolutely clear).
1158            The action now is always to scan all levels of directory, and just
1159            apply the include/exclude patterns to regular files.
1160    
1161    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
1162        --exclude_dir in the tests to avoid scanning .svn directories.
1163    
1164    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
1165        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
1166        doesn't support NULs in patterns.
1167    
1168    7.  Added some missing "const"s to declarations of static tables in
1169        pcre_compile.c and pcre_dfa_exec.c.
1170    
1171    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
1172        caused by fix #2  above. (Subsequently also a second patch to fix the
1173        first patch. And a third patch - this was a messy problem.)
1174    
1175    9.  Applied Craig's patch to remove the use of push_back().
1176    
1177    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
1178        matching function regexec().
1179    
1180    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
1181        which, however, unlike Perl's \g{...}, are subroutine calls, not back
1182        references. PCRE supports relative numbers with this syntax (I don't think
1183        Oniguruma does).
1184    
1185    12. Previously, a group with a zero repeat such as (...){0} was completely
1186        omitted from the compiled regex. However, this means that if the group
1187        was called as a subroutine from elsewhere in the pattern, things went wrong
1188        (an internal error was given). Such groups are now left in the compiled
1189        pattern, with a new opcode that causes them to be skipped at execution
1190        time.
1191    
1192    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
1193        to the way PCRE behaves:
1194    
1195        (a) A lone ] character is dis-allowed (Perl treats it as data).
1196    
1197        (b) A back reference to an unmatched subpattern matches an empty string
1198            (Perl fails the current match path).
1199    
1200        (c) A data ] in a character class must be notated as \] because if the
1201            first data character in a class is ], it defines an empty class. (In
1202            Perl it is not possible to have an empty class.) The empty class []
1203            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
1204            The negative empty class [^] matches any one character, independently
1205            of the DOTALL setting.
1206    
1207    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
1208        non-existent subpattern following a character class starting with ']' and
1209        containing () gave an internal compiling error instead of "reference to
1210        non-existent subpattern". Fortunately, when the pattern did exist, the
1211        compiled code was correct. (When scanning forwards to check for the
1212        existencd of the subpattern, it was treating the data ']' as terminating
1213        the class, so got the count wrong. When actually compiling, the reference
1214        was subsequently set up correctly.)
1215    
1216    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
1217        it was being rejected as not supported by pcre_dfa_exec(), even though
1218        other assertions are supported. I have made pcre_dfa_exec() support
1219        (*FAIL).
1220    
1221    16. The implementation of 13c above involved the invention of a new opcode,
1222        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
1223        cannot be changed at match time, I realized I could make a small
1224        improvement to matching performance by compiling OP_ALLANY instead of
1225        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1226        on the OP_ANY path.
1227    
1228    17. Compiling pcretest on Windows with readline support failed without the
1229        following two fixes: (1) Make the unistd.h include conditional on
1230        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1231    
1232    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1233        ncurses library to be included for pcretest when ReadLine support is
1234        requested, but also to allow for it to be overridden. This patch came from
1235        Daniel Bergström.
1236    
1237    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1238        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1239        any errors with the current Unicode tables. Thanks to Peter Kankowski for
1240        spotting this.
1241    
1242    
1243    Version 7.6 28-Jan-08
1244    ---------------------
1245    
1246    1.  A character class containing a very large number of characters with
1247        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
1248        overflow.
1249    
1250    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
1251        HAVE_LONG_LONG is not defined.
1252    
1253    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
1254        bring them up to date and include new features. This patch includes:
1255    
1256        - Fixed PH's badly added libz and libbz2 support.
1257        - Fixed a problem with static linking.
1258        - Added pcredemo. [But later removed - see 7 below.]
1259        - Fixed dftables problem and added an option.
1260        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
1261            HAVE_LONG_LONG.
1262        - Added readline support for pcretest.
1263        - Added an listing of the option settings after cmake has run.
1264    
1265    4.  A user submitted a patch to Makefile that makes it easy to create
1266        "pcre.dll" under mingw when using Configure/Make. I added stuff to
1267        Makefile.am that cause it to include this special target, without
1268        affecting anything else. Note that the same mingw target plus all
1269        the other distribution libraries and programs are now supported
1270        when configuring with CMake (see 6 below) instead of with
1271        Configure/Make.
1272    
1273    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
1274        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
1275        exported in the Windows port". It has not yet been confirmed that the patch
1276        solves the problem, but it does no harm.
1277    
1278    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
1279        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
1280        with CMake, and also correct the comment about stack recursion.
1281    
1282    7.  Remove the automatic building of pcredemo from the ./configure system and
1283        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
1284        of a program that users should build themselves after PCRE is installed, so
1285        building it automatically is not really right. What is more, it gave
1286        trouble in some build environments.
1287    
1288    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
1289    
1290    
1291    Version 7.5 10-Jan-08
1292    ---------------------
1293    
1294    1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
1295        values in parens when parsing an RE using the C++ wrapper."
1296    
1297    2.  Negative specials like \S did not work in character classes in UTF-8 mode.
1298        Characters greater than 255 were excluded from the class instead of being
1299        included.
1300    
1301    3.  The same bug as (2) above applied to negated POSIX classes such as
1302        [:^space:].
1303    
1304    4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1305        defined or documented. It seems to have been a typo for PCRE_STATIC, so
1306        I have changed it.
1307    
1308    5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
1309        first named subpattern) and a construct such as (?&a) would reference the
1310        first named subpattern whose name started with "a" (in other words, the
1311        length check was missing). Both these problems are fixed. "Subpattern name
1312        expected" is now given for (?&) (a zero-length name), and this patch also
1313        makes it give the same error for \k'' (previously it complained that that
1314        was a reference to a non-existent subpattern).
1315    
1316    6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
1317        this is right because (?- can be followed by option settings as well as by
1318        digits. I have, however, made the messages clearer.
1319    
1320    7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
1321        than the number used in the conditional) now cause a compile-time error.
1322        This is actually not compatible with Perl, which accepts such patterns, but
1323        treats the conditional as always being FALSE (as PCRE used to), but it
1324        seems to me that giving a diagnostic is better.
1325    
1326    8.  Change "alphameric" to the more common word "alphanumeric" in comments
1327        and messages.
1328    
1329    9.  Fix two occurrences of "backslash" in comments that should have been
1330        "backspace".
1331    
1332    10. Remove two redundant lines of code that can never be obeyed (their function
1333        was moved elsewhere).
1334    
1335    11. The program that makes PCRE's Unicode character property table had a bug
1336        which caused it to generate incorrect table entries for sequences of
1337        characters that have the same character type, but are in different scripts.
1338        It amalgamated them into a single range, with the script of the first of
1339        them. In other words, some characters were in the wrong script. There were
1340        thirteen such cases, affecting characters in the following ranges:
1341    
1342          U+002b0 - U+002c1
1343          U+0060c - U+0060d
1344          U+0061e - U+00612
1345          U+0064b - U+0065e
1346          U+0074d - U+0076d
1347          U+01800 - U+01805
1348          U+01d00 - U+01d77
1349          U+01d9b - U+01dbf
1350          U+0200b - U+0200f
1351          U+030fc - U+030fe
1352          U+03260 - U+0327f
1353          U+0fb46 - U+0fbb1
1354          U+10450 - U+1049d
1355    
1356    12. The -o option (show only the matching part of a line) for pcregrep was not
1357        compatible with GNU grep in that, if there was more than one match in a
1358        line, it showed only the first of them. It now behaves in the same way as
1359        GNU grep.
1360    
1361    13. If the -o and -v options were combined for pcregrep, it printed a blank
1362        line for every non-matching line. GNU grep prints nothing, and pcregrep now
1363        does the same. The return code can be used to tell if there were any
1364        non-matching lines.
1365    
1366    14. Added --file-offsets and --line-offsets to pcregrep.
1367    
1368    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
1369        infinitely looping recursion. The bug was that positive lookaheads were not
1370        being skipped when checking for a possible empty match (negative lookaheads
1371        and both kinds of lookbehind were skipped).
1372    
1373    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
1374        inclusion of <windows.h> to before rather than after the definition of
1375        INVALID_FILE_ATTRIBUTES (patch from David Byron).
1376    
1377    17. Specifying a possessive quantifier with a specific limit for a Unicode
1378        character property caused pcre_compile() to compile bad code, which led at
1379        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
1380        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
1381        caused the error; without that there was no problem.
1382    
1383    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
1384    
1385    19. Added --enable-pcretest-libreadline.
1386    
1387    20. In pcrecpp.cc, the variable 'count' was incremented twice in
1388        RE::GlobalReplace(). As a result, the number of replacements returned was
1389        double what it should be. I removed one of the increments, but Craig sent a
1390        later patch that removed the other one (the right fix) and added unit tests
1391        that check the return values (which was not done before).
1392    
1393    21. Several CMake things:
1394    
1395        (1) Arranged that, when cmake is used on Unix, the libraries end up with
1396            the names libpcre and libpcreposix, not just pcre and pcreposix.
1397    
1398        (2) The above change means that pcretest and pcregrep are now correctly
1399            linked with the newly-built libraries, not previously installed ones.
1400    
1401        (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
1402    
1403    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
1404        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
1405        UTF-8 newline character). The key issue is that the pattern starts .*;
1406        this means that the match must be either at the beginning, or after a
1407        newline. The bug was in the code for advancing after a failed match and
1408        checking that the new position followed a newline. It was not taking
1409        account of UTF-8 characters correctly.
1410    
1411    23. PCRE was behaving differently from Perl in the way it recognized POSIX
1412        character classes. PCRE was not treating the sequence [:...:] as a
1413        character class unless the ... were all letters. Perl, however, seems to
1414        allow any characters between [: and :], though of course it rejects as
1415        unknown any "names" that contain non-letters, because all the known class
1416        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
1417        for example, whereas PCRE did not - it did not recognize a POSIX character
1418        class. This seemed a bit dangerous, so the code has been changed to be
1419        closer to Perl. The behaviour is not identical to Perl, because PCRE will
1420        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
1421        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
1422        Perl does, and where it didn't before.
1423    
1424    24. Rewrite so as to remove the single use of %n from pcregrep because in some
1425        Windows environments %n is disabled by default.
1426    
1427    
1428    Version 7.4 21-Sep-07
1429    ---------------------
1430    
1431    1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
1432        means that a class such as [\s] counted as "explicit reference to CR or
1433        LF". That isn't really right - the whole point of the change was to try to
1434        help when there was an actual mention of one of the two characters. So now
1435        the change happens only if \r or \n (or a literal CR or LF) character is
1436        encountered.
1437    
1438    2.  The 32-bit options word was also used for 6 internal flags, but the numbers
1439        of both had grown to the point where there were only 3 bits left.
1440        Fortunately, there was spare space in the data structure, and so I have
1441        moved the internal flags into a new 16-bit field to free up more option
1442        bits.
1443    
1444    3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
1445        but did not set the internal JCHANGED flag - either of these is enough to
1446        control the way the "get" function works - but the PCRE_INFO_JCHANGED
1447        facility is supposed to tell if (?J) was ever used, so now (?J) at the
1448        start sets both bits.
1449    
1450    4.  Added options (at build time, compile time, exec time) to change \R from
1451        matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
1452    
1453    5.  doc/pcresyntax.html was missing from the distribution.
1454    
1455    6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
1456        compatibility, even though it is no longer used.
1457    
1458    7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
1459        strtoull to pcrecpp.cc to select the available functions in WIN32 when the
1460        windows.h file is present (where different names are used). [This was
1461        reversed later after testing - see 16 below.]
1462    
1463    8.  Changed all #include <config.h> to #include "config.h". There were also
1464        some further <pcre.h> cases that I changed to "pcre.h".
1465    
1466    9.  When pcregrep was used with the --colour option, it missed the line ending
1467        sequence off the lines that it output.
1468    
1469    10. It was pointed out to me that arrays of string pointers cause lots of
1470        relocations when a shared library is dynamically loaded. A technique of
1471        using a single long string with a table of offsets can drastically reduce
1472        these. I have refactored PCRE in four places to do this. The result is
1473        dramatic:
1474    
1475          Originally:                          290
1476          After changing UCP table:            187
1477          After changing error message table:   43
1478          After changing table of "verbs"       36
1479          After changing table of Posix names   22
1480    
1481        Thanks to the folks working on Gregex for glib for this insight.
1482    
1483    11. --disable-stack-for-recursion caused compiling to fail unless -enable-
1484        unicode-properties was also set.
1485    
1486    12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
1487    
1488    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
1489        checked only for CRLF.
1490    
1491    14. Added casts to pcretest.c to avoid compiler warnings.
1492    
1493    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
1494    
1495    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
1496        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
1497        entirely. This removes changes made in 7 above.
1498    
1499    17. The CMake files have been updated, and there is now more information about
1500        building with CMake in the NON-UNIX-USE document.
1501    
1502    
1503    Version 7.3 28-Aug-07
1504  ---------------------  ---------------------
1505    
1506   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 145  Version 7.3 20-Aug-07 Line 1644  Version 7.3 20-Aug-07
1644    
1645  25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.  25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
1646    
1647  26. Patterns such as [\P{Yi}A] which include \p or \P and just one other  26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
1648      character were causing crashes (broken optimization).      character were causing crashes (broken optimization).
1649    
1650  27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing  27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
1651      \p or \P) caused a compile-time loop.      \p or \P) caused a compile-time loop.
1652    
1653  28. More problems have arisen in unanchored patterns when CRLF is a valid line  28. More problems have arisen in unanchored patterns when CRLF is a valid line
1654      break. For example, the unstudied pattern [\r\n]A does not match the string      break. For example, the unstudied pattern [\r\n]A does not match the string
1655      "\r\nA" because change 7.0/46 below moves the current point on by two      "\r\nA" because change 7.0/46 below moves the current point on by two
1656      characters after failing to match at the start. However, the pattern \nA      characters after failing to match at the start. However, the pattern \nA
1657      *does* match, because it doesn't start till \n, and if [\r\n]A is studied,      *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
1658      the same is true. There doesn't seem any very clean way out of this, but      the same is true. There doesn't seem any very clean way out of this, but
1659      what I have chosen to do makes the common cases work: PCRE now takes note      what I have chosen to do makes the common cases work: PCRE now takes note
1660      of whether there can be an explicit match for \r or \n anywhere in the      of whether there can be an explicit match for \r or \n anywhere in the
1661      pattern, and if so, 7.0/46 no longer applies. As part of this change,      pattern, and if so, 7.0/46 no longer applies. As part of this change,
1662      there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled      there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
1663      pattern has explicit CR or LF references.      pattern has explicit CR or LF references.
1664    
1665    29. Added (*CR) etc for changing newline setting at start of pattern.
1666    
1667    
1668  Version 7.2 19-Jun-07  Version 7.2 19-Jun-07

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