ViewVC logotype

Diff of /code/trunk/ChangeLog

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 377 by ph10, Sun Mar 1 12:07:19 2009 UTC revision 738 by ph10, Fri Oct 21 09:04:01 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
4  Version 7.9 xx-xxx-09  Version 8.20 21-Oct-2011
5    ------------------------
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.
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.
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.
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.
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.
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.
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.
54    8.  If (*THEN) was present in the first (true) branch of a conditional group,
55        it was not handled as intended. [But see 16 below.]
57    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
58        Sheri Pierce.
60    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
61        the first byte in a match must be "a".
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.
69    12. In some environments, the output of pcretest -C is CRLF terminated. This
70        broke RunTest's code that checks for the link size. A single white space
71        character after the value is now allowed for.
73    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
74        For "fr", it uses the Windows-specific input and output files.
76    14. If (*THEN) appeared in a group that was called recursively or as a
77        subroutine, it did not work as intended. [But see next item.]
79    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
80        pattern fragments (but not containing any | characters). If A and B are
81        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
82        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
83        D. In other words, Perl considers parentheses that do not contain any |
84        characters to be part of a surrounding alternative, whereas PCRE was
85        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
86        differently. PCRE now behaves in the same way as Perl, except in the case
87        of subroutine/recursion calls such as (?1) which have in any case always
88        been different (but PCRE had them first :-).
90    16. Related to 15 above: Perl does not treat the | in a conditional group as
91        creating alternatives. Such a group is treated in the same way as an
92        ordinary group without any | characters when processing (*THEN). PCRE has
93        been changed to match Perl's behaviour.
95    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
96        RunGrepTest script failed.
98    18. Change 22 for version 13 caused atomic groups to use more stack. This is
99        inevitable for groups that contain captures, but it can lead to a lot of
100        stack use in large patterns. The old behaviour has been restored for atomic
101        groups that do not contain any capturing parentheses.
103    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
104        suppress the check for a minimum subject length at run time. (If it was
105        given to pcre_exec() or pcre_dfa_exec() it did work.)
107    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
108        fail to work when decoding hex characters in data strings in EBCDIC
109        environments.
111    21. It appears that in at least one Mac OS environment, the isxdigit() function
112        is implemented as a macro that evaluates to its argument more than once,
113        contravening the C 90 Standard (I haven't checked a later standard). There
114        was an instance in pcretest which caused it to go wrong when processing
115        \x{...} escapes in subject strings. The has been rewritten to avoid using
116        things like p++ in the argument of isxdigit().
119    Version 8.13 16-Aug-2011
120    ------------------------
122    1.  The Unicode data tables have been updated to Unicode 6.0.0.
124    2.  Two minor typos in pcre_internal.h have been fixed.
126    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
127        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
128        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
130    4.  There were a number of related bugs in the code for matching backrefences
131        caselessly in UTF-8 mode when codes for the characters concerned were
132        different numbers of bytes. For example, U+023A and U+2C65 are an upper
133        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
134        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
135        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
136        2-byte code at the end of the subject (it thought there wasn't enough data
137        left).
139    5.  Comprehensive information about what went wrong is now returned by
140        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
141        as the output vector has at least 2 elements. The offset of the start of
142        the failing character and a reason code are placed in the vector.
144    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
145        now returned is for the first byte of the failing character, instead of the
146        last byte inspected. This is an incompatible change, but I hope it is small
147        enough not to be a problem. It makes the returned offset consistent with
148        pcre_exec() and pcre_dfa_exec().
150    7.  pcretest now gives a text phrase as well as the error number when
151        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
152        failure, the offset and reason code are output.
154    8.  When \R was used with a maximizing quantifier it failed to skip backwards
155        over a \r\n pair if the subsequent match failed. Instead, it just skipped
156        back over a single character (\n). This seems wrong (because it treated the
157        two characters as a single entity when going forwards), conflicts with the
158        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
159        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
160        has been changed.
162    9.  Some internal refactoring has changed the processing so that the handling
163        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
164        time (the PCRE_DOTALL option was changed this way some time ago: version
165        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
166        which was always a bit of a fudge. It also means that there is one less
167        argument for the match() function, which reduces its stack requirements
168        slightly. This change also fixes an incompatibility with Perl: the pattern
169        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
171    10. More internal refactoring has drastically reduced the number of recursive
172        calls to match() for possessively repeated groups such as (abc)++ when
173        using pcre_exec().
175    11. While implementing 10, a number of bugs in the handling of groups were
176        discovered and fixed:
178        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
179        (a|)*(?1) gave a compile-time internal error.
180        ((a|)+)+  did not notice that the outer group could match an empty string.
181        (^a|^)+   was not marked as anchored.
182        (.*a|.*)+ was not marked as matching at start or after a newline.
184    12. Yet more internal refactoring has removed another argument from the match()
185        function. Special calls to this function are now indicated by setting a
186        value in a variable in the "match data" data block.
188    13. Be more explicit in pcre_study() instead of relying on "default" for
189        opcodes that mean there is no starting character; this means that when new
190        ones are added and accidentally left out of pcre_study(), testing should
191        pick them up.
193    14. The -s option of pcretest has been documented for ages as being an old
194        synonym of -m (show memory usage). I have changed it to mean "force study
195        for every regex", that is, assume /S for every regex. This is similar to -i
196        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
197        using it. It makes it easier to run collections of tests with and without
198        study enabled, and thereby test pcre_study() more easily. All the standard
199        tests are now run with and without -s (but some patterns can be marked as
200        "never study" - see 20 below).
202    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
203        restoration of the capturing data to the outer values was not happening
204        correctly.
206    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
207        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
208        pattern had matched an empty string, and so incorrectly returned a no
209        match.
211    17. There was optimizing code for the last branch of non-capturing parentheses,
212        and also for the obeyed branch of a conditional subexpression, which used
213        tail recursion to cut down on stack usage. Unfortunately, now that there is
214        the possibility of (*THEN) occurring in these branches, tail recursion is
215        no longer possible because the return has to be checked for (*THEN). These
216        two optimizations have therefore been removed. [But see 8.20/11 above.]
218    18. If a pattern containing \R was studied, it was assumed that \R always
219        matched two bytes, thus causing the minimum subject length to be
220        incorrectly computed because \R can also match just one byte.
222    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
223        was incorrectly computed.
225    20. If /S is present twice on a test pattern in pcretest input, it now
226        *disables* studying, thereby overriding the use of -s on the command line
227        (see 14 above). This is necessary for one or two tests to keep the output
228        identical in both cases.
230    21. When (*ACCEPT) was used in an assertion that matched an empty string and
231        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
233    22. When an atomic group that contained a capturing parenthesis was
234        successfully matched, but the branch in which it appeared failed, the
235        capturing was not being forgotten if a higher numbered group was later
236        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
237        group 1 to "a", when in fact it should be unset. This applied to multi-
238        branched capturing and non-capturing groups, repeated or not, and also to
239        positive assertions (capturing in negative assertions does not happen
240        in PCRE) and also to nested atomic groups.
242    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
243        subject after a captured substring, to make it easier to tell which of a
244        number of identical substrings has been captured.
246    24. The way atomic groups are processed by pcre_exec() has been changed so that
247        if they are repeated, backtracking one repetition now resets captured
248        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
249        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
250        "aaa". Previously, it would have been "a". As part of this code
251        refactoring, the way recursive calls are handled has also been changed.
253    25. If an assertion condition captured any substrings, they were not passed
254        back unless some other capturing happened later. For example, if
255        (?(?=(a))a) was matched against "a", no capturing was returned.
257    26. When studying a pattern that contained subroutine calls or assertions,
258        the code for finding the minimum length of a possible match was handling
259        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
260        group 1 called group 2 while simultaneously a separate group 2 called group
261        1). A stack overflow occurred in this case. I have fixed this by limiting
262        the recursion depth to 10.
264    27. Updated RunTest.bat in the distribution to the version supplied by Tom
265        Fortmann. This supports explicit test numbers on the command line, and has
266        argument validation and error reporting.
268    28. An instance of \X with an unlimited repeat could fail if at any point the
269        first character it looked at was a mark character.
271    29. Some minor code refactoring concerning Unicode properties and scripts
272        should reduce the stack requirement of match() slightly.
274    30. Added the '=' option to pcretest to check the setting of unused capturing
275        slots at the end of the pattern, which are documented as being -1, but are
276        not included in the return count.
278    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
279        compiled something random. Now it gives a compile-time error (as does
280        Perl).
282    32. A *MARK encountered during the processing of a positive assertion is now
283        recorded and passed back (compatible with Perl).
285    33. If --only-matching or --colour was set on a pcregrep call whose pattern
286        had alternative anchored branches, the search for a second match in a line
287        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
288        matched the line "0102" twice. The same bug affected patterns that started
289        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
290        twice.
292    34. Previously, PCRE did not allow quantification of assertions. However, Perl
293        does, and because of capturing effects, quantifying parenthesized
294        assertions may at times be useful. Quantifiers are now allowed for
295        parenthesized assertions.
297    35. A minor code tidy in pcre_compile() when checking options for \R usage.
299    36. \g was being checked for fancy things in a character class, when it should
300        just be a literal "g".
302    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
303        appearance of a nested POSIX class supersedes an apparent external class.
304        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
305        unescaped square brackets may also appear as part of class names. For
306        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
307        more like Perl. (But see 8.20/1 above.)
309    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
310        was because it thought it was \N{name}, which is not supported).
312    39. Add minix to OS list not supporting the -S option in pcretest.
314    40. PCRE tries to detect cases of infinite recursion at compile time, but it
315        cannot analyze patterns in sufficient detail to catch mutual recursions
316        such as ((?1))((?2)). There is now a runtime test that gives an error if a
317        subgroup is called recursively as a subpattern for a second time at the
318        same position in the subject string. In previous releases this might have
319        been caught by the recursion limit, or it might have run out of stack.
321    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
322        happen only once. PCRE was, however incorrectly giving a compile time error
323        "recursive call could loop indefinitely" because it cannot analyze the
324        pattern in sufficient detail. The compile time test no longer happens when
325        PCRE is compiling a conditional subpattern, but actual runaway loops are
326        now caught at runtime (see 40 above).
328    42. It seems that Perl allows any characters other than a closing parenthesis
329        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
330        has been changed to be the same.
332    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
333        as not to get warnings when autogen.sh is called. Also changed
334        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
336    44. To help people who use pcregrep to scan files containing exceedingly long
337        lines, the following changes have been made:
339        (a) The default value of the buffer size parameter has been increased from
340            8K to 20K. (The actual buffer used is three times this size.)
342        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
343            PCRE is built.
345        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
346            to be set at run time.
348        (d) Numerical values in pcregrep options can be followed by K or M, for
349            example --buffer-size=50K.
351        (e) If a line being scanned overflows pcregrep's buffer, an error is now
352            given and the return code is set to 2.
354    45. Add a pointer to the latest mark to the callout data block.
356    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
357        partial match of an empty string instead of no match. This was specific to
358        the use of ".".
360    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
361        complete match instead of a partial match. This bug was dependent on both
362        the PCRE_UTF8 and PCRE_DOTALL options being set.
364    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
365        starting byte set, because \b was not being ignored.
368    Version 8.12 15-Jan-2011
369    ------------------------
371    1.  Fixed some typos in the markup of the man pages, and wrote a script that
372        checks for such things as part of the documentation building process.
374    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
375        --match-limit and --recursion-limit options (added for 8.11). In
376        particular, this made one of the standard tests fail. (The integer value
377        went into the wrong half of a long int.)
379    3.  If the --colour option was given to pcregrep with -v (invert match), it
380        did strange things, either producing crazy output, or crashing. It should,
381        of course, ignore a request for colour when reporting lines that do not
382        match.
384    4.  Another pcregrep bug caused similar problems if --colour was specified with
385        -M (multiline) and the pattern match finished with a line ending.
387    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
388        matched in multiline mode, the following line was shown as part of the
389        match. This seems wrong, so I have changed it.
391    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
392        the check for further matches in the same line (so they could be coloured)
393        to overrun the end of the current line. If another match was found, it was
394        incorrectly shown (and then shown again when found in the next line).
396    7.  If pcregrep was compiled under Windows, there was a reference to the
397        function pcregrep_exit() before it was defined. I am assuming this was
398        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
399        reported by a user. I've moved the definition above the reference.
402    Version 8.11 10-Dec-2010
403    ------------------------
405    1.  (*THEN) was not working properly if there were untried alternatives prior
406        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
407        backtracked to try for "b" instead of moving to the next alternative branch
408        at the same level (in this case, to look for "c"). The Perl documentation
409        is clear that when (*THEN) is backtracked onto, it goes to the "next
410        alternative in the innermost enclosing group".
412    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
413        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
414        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
415        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
416        (*THEN).
418    3.  If \s appeared in a character class, it removed the VT character from
419        the class, even if it had been included by some previous item, for example
420        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
421        of \s, but is part of the POSIX "space" class.)
423    4.  A partial match never returns an empty string (because you can always
424        match an empty string at the end of the subject); however the checking for
425        an empty string was starting at the "start of match" point. This has been
426        changed to the "earliest inspected character" point, because the returned
427        data for a partial match starts at this character. This means that, for
428        example, /(?<=abc)def/ gives a partial match for the subject "abc"
429        (previously it gave "no match").
431    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
432        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
433        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
434        has an implication that the given string is incomplete (because a partial
435        match is preferred over a full match). For this reason, these items now
436        give a partial match in this situation. [Aside: previously, the one case
437        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
438        match rather than a full match, which was wrong by the old rules, but is
439        now correct.]
441    6.  There was a bug in the handling of #-introduced comments, recognized when
442        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
443        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
444        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
445        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
446        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
447        places in pcre_compile().
449    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
450        comments when looking ahead for named forward references to subpatterns,
451        the only newline sequence it recognized was NL. It now handles newlines
452        according to the set newline convention.
454    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
455        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
456        cater for a lack of strerror(). These oversights have been fixed.
458    9.  Added --match-limit and --recursion-limit to pcregrep.
460    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
462    11. When the -o option was used, pcregrep was setting a return code of 1, even
463        when matches were found, and --line-buffered was not being honoured.
465    12. Added an optional parentheses number to the -o and --only-matching options
466        of pcregrep.
468    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
469        can match an empty string. The code to do it in pcretest and pcredemo
470        needed fixing:
472        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
473            only one byte after an empty string match just before CRLF (this case
474            just got forgotten; "any" and "anycrlf" were OK).
476        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
477            mode when an empty string match preceded an ASCII character followed by
478            a non-ASCII character. (The code for advancing by one character rather
479            than one byte was nonsense.)
481        (c) The pcredemo.c sample program did not have any code at all to handle
482            the cases when CRLF is a valid newline sequence.
484    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
485        as a starting offset was within the subject string. There is now a new
486        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
487        negative or greater than the length of the string. In order to test this,
488        pcretest is extended to allow the setting of negative starting offsets.
490    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
491        starting offset points to the beginning of a UTF-8 character was
492        unnecessarily clumsy. I tidied it up.
494    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
495        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
497    17. Nobody had reported that the --include_dir option, which was added in
498        release 7.7 should have been called --include-dir (hyphen, not underscore)
499        for compatibility with GNU grep. I have changed it to --include-dir, but
500        left --include_dir as an undocumented synonym, and the same for
501        --exclude-dir, though that is not available in GNU grep, at least as of
502        release 2.5.4.
504    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
505        characters from a string of bytes) have been redefined so as not to use
506        loops, in order to improve performance in some environments. At the same
507        time, I abstracted some of the common code into auxiliary macros to save
508        repetition (this should not affect the compiled code).
510    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
511        compile-time error is now given if \c is not followed by an ASCII
512        character, that is, a byte less than 128. (In EBCDIC mode, the code is
513        different, and any byte value is allowed.)
515    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
516        START_OPTIMIZE option, which is now allowed at compile time - but just
517        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
518        to pcregrep and other applications that have no direct access to PCRE
519        options. The new /Y option in pcretest sets this option when calling
520        pcre_compile().
522    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
523        back references. Groups containing recursive back references were forced to
524        be atomic by that change, but in the case of named groups, the amount of
525        memory required was incorrectly computed, leading to "Failed: internal
526        error: code overflow". This has been fixed.
528    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
529        pcretest.c, to avoid build problems in some Borland environments.
532    Version 8.10 25-Jun-2010
533    ------------------------
535    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
536        THEN.
538    2.  (*ACCEPT) was not working when inside an atomic group.
540    3.  Inside a character class, \B is treated as a literal by default, but
541        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
542        causes the error). The code is unchanged, but I tidied the documentation.
544    4.  Inside a character class, PCRE always treated \R and \X as literals,
545        whereas Perl faults them if its -w option is set. I have changed PCRE so
546        that it faults them when PCRE_EXTRA is set.
548    5.  Added support for \N, which always matches any character other than
549        newline. (It is the same as "." when PCRE_DOTALL is not set.)
551    6.  When compiling pcregrep with newer versions of gcc which may have
552        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
553        declared with attribute warn_unused_result" were given. Just casting the
554        result to (void) does not stop the warnings; a more elaborate fudge is
555        needed. I've used a macro to implement this.
557    7.  Minor change to pcretest.c to avoid a compiler warning.
559    8.  Added four artifical Unicode properties to help with an option to make
560        \s etc use properties (see next item). The new properties are: Xan
561        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
563    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
564        use Unicode properties. (*UCP) at the start of a pattern can be used to set
565        this option. Modified pcretest to add /W to test this facility. Added
566        REG_UCP to make it available via the POSIX interface.
568    10. Added --line-buffered to pcregrep.
570    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
571        studied, and the match started with a letter with a code point greater than
572        127 whose first byte was different to the first byte of the other case of
573        the letter, the other case of this starting letter was not recognized
574        (#976).
576    12. If a pattern that was studied started with a repeated Unicode property
577        test, for example, \p{Nd}+, there was the theoretical possibility of
578        setting up an incorrect bitmap of starting bytes, but fortunately it could
579        not have actually happened in practice until change 8 above was made (it
580        added property types that matched character-matching opcodes).
582    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
583        possible starting bytes for non-anchored patterns.
585    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
586        \R, and also a number of cases that involve Unicode properties, both
587        explicit and implicit when PCRE_UCP is set.
589    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
590        input, it could crash or give wrong results if characters with values
591        greater than 0xc0 were present in the subject string. (Detail: it assumed
592        UTF-8 input when processing these items.)
594    16. Added a lot of (int) casts to avoid compiler warnings in systems where
595        size_t is 64-bit (#991).
597    17. Added a check for running out of memory when PCRE is compiled with
598        --disable-stack-for-recursion (#990).
600    18. If the last data line in a file for pcretest does not have a newline on
601        the end, a newline was missing in the output.
603    19. The default pcre_chartables.c file recognizes only ASCII characters (values
604        less than 128) in its various bitmaps. However, there is a facility for
605        generating tables according to the current locale when PCRE is compiled. It
606        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
607        characters, are recognized by isspace() and therefore were getting set in
608        these tables, and indeed these tables seem to approximate to ISO 8859. This
609        caused a problem in UTF-8 mode when pcre_study() was used to create a list
610        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
611        which of course cannot start UTF-8 characters. I have changed the code so
612        that only real ASCII characters (less than 128) and the correct starting
613        bytes for UTF-8 encodings are set for characters greater than 127 when in
614        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
615        altogether.)
617    20. Added the /T option to pcretest so as to be able to run tests with non-
618        standard character tables, thus making it possible to include the tests
619        used for 19 above in the standard set of tests.
621    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
622        reference to a subpattern the other side of a comment that contains an
623        opening parenthesis caused either an internal compiling error, or a
624        reference to the wrong subpattern.
627    Version 8.02 19-Mar-2010
628    ------------------------
630    1.  The Unicode data tables have been updated to Unicode 5.2.0.
632    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
633        configured.
635    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
636        original author of that file, following a query about its status.
638    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
639        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
641    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
642        quantifier applied to a forward-referencing subroutine call, could compile
643        incorrect code or give the error "internal error: previously-checked
644        referenced subpattern not found".
646    6.  Both MS Visual Studio and Symbian OS have problems with initializing
647        variables to point to external functions. For these systems, therefore,
648        pcre_malloc etc. are now initialized to local functions that call the
649        relevant global functions.
651    7.  There were two entries missing in the vectors called coptable and poptable
652        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
653        I've fixed the data, and added a kludgy way of testing at compile time that
654        the lengths are correct (equal to the number of opcodes).
656    8.  Following on from 7, I added a similar kludge to check the length of the
657        eint vector in pcreposix.c.
659    9.  Error texts for pcre_compile() are held as one long string to avoid too
660        much relocation at load time. To find a text, the string is searched,
661        counting zeros. There was no check for running off the end of the string,
662        which could happen if a new error number was added without updating the
663        string.
665    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
667    11. \K was not working if it appeared in an atomic group or in a group that
668        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
669        \K is "not well defined" if used in an assertion. PCRE now accepts it if
670        the assertion is positive, but not if it is negative.
672    12. Change 11 fortuitously reduced the size of the stack frame used in the
673        "match()" function of pcre_exec.c by one pointer. Forthcoming
674        implementation of support for (*MARK) will need an extra pointer on the
675        stack; I have reserved it now, so that the stack frame size does not
676        decrease.
678    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
679        item in branch that calls a recursion is a subroutine call - as in the
680        second branch in the above example - was incorrectly given the compile-
681        time error "recursive call could loop indefinitely" because pcre_compile()
682        was not correctly checking the subroutine for matching a non-empty string.
684    14. The checks for overrunning compiling workspace could trigger after an
685        overrun had occurred. This is a "should never occur" error, but it can be
686        triggered by pathological patterns such as hundreds of nested parentheses.
687        The checks now trigger 100 bytes before the end of the workspace.
689    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
692    Version 8.01 19-Jan-2010
693    ------------------------
695    1.  If a pattern contained a conditional subpattern with only one branch (in
696        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
697        computed the wrong minimum data length (which is of course zero for such
698        subpatterns). This could cause incorrect "no match" results.
700    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
701        the pattern is reset in the first branch, pcre_compile() failed with
702        "internal error: code overflow at offset...". This happened only when
703        the reset was to the original external option setting. (An optimization
704        abstracts leading options settings into an external setting, which was the
705        cause of this.)
707    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
708        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
709        assertion pattern did not match (meaning that the assertion was true), it
710        was incorrectly treated as false if the SKIP had been reached during the
711        matching. This also applied to assertions used as conditions.
713    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
714        assertion subpattern, including such a pattern used as a condition,
715        unpredictable results occurred, instead of the error return
718    5.  The C++ GlobalReplace function was not working like Perl for the special
719        situation when an empty string is matched. It now does the fancy magic
720        stuff that is necessary.
722    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
723        removed. (These were left over from very, very early versions of PCRE.)
725    7.  Some cosmetic changes to the code to make life easier when compiling it
726        as part of something else:
728        (a) Change DEBUG to PCRE_DEBUG.
730        (b) In pcre_compile(), rename the member of the "branch_chain" structure
731            called "current" as "current_branch", to prevent a collision with the
732            Linux macro when compiled as a kernel module.
734        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
735            prevent a collision with the Linux macro when compiled as a kernel
736            module.
738    8.  In pcre_compile() there are some checks for integer overflows that used to
739        cast potentially large values to (double). This has been changed to that
740        when building, a check for int64_t is made, and if it is found, it is used
741        instead, thus avoiding the use of floating point arithmetic. (There is no
742        other use of FP in PCRE.) If int64_t is not found, the fallback is to
743        double.
745    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
746        2005 (difference between two addresses compared to an unsigned value).
748    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
749        custom one, because of the following reported problem in Windows:
751          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
752              under Win32.
753          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
754              therefore missing the function definition.
755          - The compiler thus generates a "C" signature for the test function.
756          - The linker fails to find the "C" function.
757          - PCRE fails to configure if asked to do so against libbz2.
759    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
760        messages were output:
762          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
763          rerunning libtoolize, to keep the correct libtool macros in-tree.
764          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
766        I have done both of these things.
768    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
769        most of the time, it *can* run out if it is given a pattern that contains a
770        runaway infinite recursion. I updated the discussion in the pcrestack man
771        page.
773    13. Now that we have gone to the x.xx style of version numbers, the minor
774        version may start with zero. Using 08 or 09 is a bad idea because users
775        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
776        interpreted as invalid octal numbers. I've updated the previous comment in
777        configure.ac, and also added a check that gives an error if 08 or 09 are
778        used.
780    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
781        causing partial matching to fail when the end of the subject matched \W
782        in a UTF-8 pattern where \W was quantified with a minimum of 3.
784    15. There were some discrepancies between the declarations in pcre_internal.h
785        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
786        their definitions. The declarations used "const uschar *" and the
787        definitions used USPTR. Even though USPTR is normally defined as "const
788        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
789        reported that: "This difference in casting confuses some C++ compilers, for
790        example, SunCC recognizes above declarations as different functions and
791        generates broken code for hbpcre." I have changed the declarations to use
792        USPTR.
794    16. GNU libtool is named differently on some systems. The autogen.sh script now
795        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
796        (FreeBSD).
798    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
799        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
800        comment: "Figure out how to create a longlong from a string: strtoll and
801        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
802        instance, but it only takes 2 args instead of 3!"
804    18. A subtle bug concerned with back references has been fixed by a change of
805        specification, with a corresponding code fix. A pattern such as
806        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
807        refers, was giving matches when it shouldn't. For example, xa=xaaa would
808        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
809        same bug. Such groups have to be quantified to be useful, or contained
810        inside another quantified group. (If there's no repetition, the reference
811        can never match.) The problem arises because, having left the group and
812        moved on to the rest of the pattern, a later failure that backtracks into
813        the group uses the captured value from the final iteration of the group
814        rather than the correct earlier one. I have fixed this in PCRE by forcing
815        any group that contains a reference to itself to be an atomic group; that
816        is, there cannot be any backtracking into it once it has completed. This is
817        similar to recursive and subroutine calls.
820    Version 8.00 19-Oct-09
821    ----------------------
823    1.  The table for translating pcre_compile() error codes into POSIX error codes
824        was out-of-date, and there was no check on the pcre_compile() error code
825        being within the table. This could lead to an OK return being given in
826        error.
828    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
829        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
830        in a Windows environment.
832    3.  The pcregrep --count option prints the count for each file even when it is
833        zero, as does GNU grep. However, pcregrep was also printing all files when
834        --files-with-matches was added. Now, when both options are given, it prints
835        counts only for those files that have at least one match. (GNU grep just
836        prints the file name in this circumstance, but including the count seems
837        more useful - otherwise, why use --count?) Also ensured that the
838        combination -clh just lists non-zero counts, with no names.
840    4.  The long form of the pcregrep -F option was incorrectly implemented as
841        --fixed_strings instead of --fixed-strings. This is an incompatible change,
842        but it seems right to fix it, and I didn't think it was worth preserving
843        the old behaviour.
845    5.  The command line items --regex=pattern and --regexp=pattern were not
846        recognized by pcregrep, which required --regex pattern or --regexp pattern
847        (with a space rather than an '='). The man page documented the '=' forms,
848        which are compatible with GNU grep; these now work.
850    6.  No libpcreposix.pc file was created for pkg-config; there was just
851        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
853    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
854        when UCP support is not needed, by modifying the Python script that
855        generates it from Unicode data files. This should not matter if the module
856        is correctly used as a library, but I received one complaint about 50K of
857        unwanted data. My guess is that the person linked everything into his
858        program rather than using a library. Anyway, it does no harm.
860    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
861        was a minimum greater than 1 for a wide character in a possessive
862        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
863        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
864        character. Chaos in the form of incorrect output or a compiling loop could
865        result.
867    9.  The restrictions on what a pattern can contain when partial matching is
868        requested for pcre_exec() have been removed. All patterns can now be
869        partially matched by this function. In addition, if there are at least two
870        slots in the offset vector, the offset of the earliest inspected character
871        for the match and the offset of the end of the subject are set in them when
872        PCRE_ERROR_PARTIAL is returned.
874    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
875        synonymous with PCRE_PARTIAL, for backwards compatibility, and
876        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
877        and may be more useful for multi-segment matching.
879    11. Partial matching with pcre_exec() is now more intuitive. A partial match
880        used to be given if ever the end of the subject was reached; now it is
881        given only if matching could not proceed because another character was
882        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
883        string "Z", which now yields "no match" instead of "partial match". In the
884        case of pcre_dfa_exec(), "no match" is given if every matching path for the
885        final character ended with (*FAIL).
887    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
888        if the pattern had a "must contain" character that was already found in the
889        earlier partial match, unless partial matching was again requested. For
890        example, with the pattern /dog.(body)?/, the "must contain" character is
891        "g". If the first part-match was for the string "dog", restarting with
892        "sbody" failed. This bug has been fixed.
894    13. The string returned by pcre_dfa_exec() after a partial match has been
895        changed so that it starts at the first inspected character rather than the
896        first character of the match. This makes a difference only if the pattern
897        starts with a lookbehind assertion or \b or \B (\K is not supported by
898        pcre_dfa_exec()). It's an incompatible change, but it makes the two
899        matching functions compatible, and I think it's the right thing to do.
901    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
902        so that the demonstration program is easily available in environments where
903        PCRE has not been installed from source.
905    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
906        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
907        library.
909    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
910        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
911        is not the first non-POSIX option to be added. Clearly some people find
912        these options useful.
914    17. If a caller to the POSIX matching function regexec() passes a non-zero
915        value for nmatch with a NULL value for pmatch, the value of
916        nmatch is forced to zero.
918    18. RunGrepTest did not have a test for the availability of the -u option of
919        the diff command, as RunTest does. It now checks in the same way as
920        RunTest, and also checks for the -b option.
922    19. If an odd number of negated classes containing just a single character
923        interposed, within parentheses, between a forward reference to a named
924        subpattern and the definition of the subpattern, compilation crashed with
925        an internal error, complaining that it could not find the referenced
926        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
927        [The bug was that it was starting one character too far in when skipping
928        over the character class, thus treating the ] as data rather than
929        terminating the class. This meant it could skip too much.]
931    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
932        /g option in pcretest when the pattern contains \K, which makes it possible
933        to have an empty string match not at the start, even when the pattern is
934        anchored. Updated pcretest and pcredemo to use this option.
936    21. If the maximum number of capturing subpatterns in a recursion was greater
937        than the maximum at the outer level, the higher number was returned, but
938        with unset values at the outer level. The correct (outer level) value is
939        now given.
941    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
942        PCRE did not set those parentheses (unlike Perl). I have now found a way to
943        make it do so. The string so far is captured, making this feature
944        compatible with Perl.
946    23. The tests have been re-organized, adding tests 11 and 12, to make it
947        possible to check the Perl 5.10 features against Perl 5.10.
949    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
950        pattern matches a fixed length string. PCRE did not allow this; now it
951        does. Neither allows recursion.
953    25. I finally figured out how to implement a request to provide the minimum
954        length of subject string that was needed in order to match a given pattern.
955        (It was back references and recursion that I had previously got hung up
956        on.) This code has now been added to pcre_study(); it finds a lower bound
957        to the length of subject needed. It is not necessarily the greatest lower
958        bound, but using it to avoid searching strings that are too short does give
959        some useful speed-ups. The value is available to calling programs via
960        pcre_fullinfo().
962    26. While implementing 25, I discovered to my embarrassment that pcretest had
963        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
964        study optimizations had never been tested with that matching function.
965        Oops. What is worse, even when it was passed study data, there was a bug in
966        pcre_dfa_exec() that meant it never actually used it. Double oops. There
967        were also very few tests of studied patterns with pcre_dfa_exec().
969    27. If (?| is used to create subpatterns with duplicate numbers, they are now
970        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
971        on the other side of the coin, they are no longer allowed to have different
972        names, because these cannot be distinguished in PCRE, and this has caused
973        confusion. (This is a difference from Perl.)
975    28. When duplicate subpattern names are present (necessarily with different
976        numbers, as required by 27 above), and a test is made by name in a
977        conditional pattern, either for a subpattern having been matched, or for
978        recursion in such a pattern, all the associated numbered subpatterns are
979        tested, and the overall condition is true if the condition is true for any
980        one of them. This is the way Perl works, and is also more like the way
981        testing by number works.
984    Version 7.9 11-Apr-09
985  ---------------------  ---------------------
987  1.  When building with support for bzlib/zlib (pcregrep) and/or readline  1.  When building with support for bzlib/zlib (pcregrep) and/or readline
988      (pcretest), all targets were linked against these libraries. This included      (pcretest), all targets were linked against these libraries. This included
989      libpcre, libpcreposix, and libpcrecpp, even though they do not use these      libpcre, libpcreposix, and libpcrecpp, even though they do not use these
990      libraries. This caused unwanted dependencies to be created. This problem      libraries. This caused unwanted dependencies to be created. This problem
991      has been fixed, and now only pcregrep is linked with bzlib/zlib and only      has been fixed, and now only pcregrep is linked with bzlib/zlib and only
992      pcretest is linked with readline.      pcretest is linked with readline.
994  2.  The "typedef int BOOL" in pcre_internal.h that was included inside the  2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
995      "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been      "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
996      moved outside it again, because FALSE and TRUE are already defined in AIX,      moved outside it again, because FALSE and TRUE are already defined in AIX,
997      but BOOL is not.      but BOOL is not.
999  3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and  3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
1000      PCRE_MATCH_LIMIT_RETURSION values as ints, when they should be long ints.      PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
1002  4.  The pcregrep documentation said spaces were inserted as well as colons (or  4.  The pcregrep documentation said spaces were inserted as well as colons (or
1003      hyphens) following file names and line numbers when outputting matching      hyphens) following file names and line numbers when outputting matching
1004      lines. This is not true; no spaces are inserted. I have also clarified the      lines. This is not true; no spaces are inserted. I have also clarified the
1005      wording for the --colour (or --color) option.      wording for the --colour (or --color) option.
1007  5.  When --colour was used with -o, the list of matching strings was not  5.  In pcregrep, when --colour was used with -o, the list of matching strings
1008      coloured; this is different to GNU grep, so I have changed it to be the      was not coloured; this is different to GNU grep, so I have changed it to be
1009      same.      the same.
1011    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
1012        each matching line was coloured. Now it goes on to look for further matches
1013        of any of the test patterns, which is the same behaviour as GNU grep.
1015    7.  A pattern that could match an empty string could cause pcregrep to loop; it
1016        doesn't make sense to accept an empty string match in pcregrep, so I have
1017        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
1018        seems to be how GNU grep behaves.
1020    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1021        start or after a newline", because the conditional assertion was not being
1022        correctly handled. The rule now is that both the assertion and what follows
1023        in the first alternative must satisfy the test.
1025    9.  If auto-callout was enabled in a pattern with a conditional group whose
1026        condition was an assertion, PCRE could crash during matching, both with
1027        pcre_exec() and pcre_dfa_exec().
1029    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1030        used for matching.
1032    11. Unicode property support in character classes was not working for
1033        characters (bytes) greater than 127 when not in UTF-8 mode.
1035    12. Added the -M command line option to pcretest.
1037    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1039    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1041    16. Added comments and documentation about mis-use of no_arg in the C++
1042        wrapper.
1044    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1045        from Martin Jerabek that uses macro names for all relevant character and
1046        string constants.
1048    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1049        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1050        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1051        these, but not everybody uses configure.
1053    19. A conditional group that had only one branch was not being correctly
1054        recognized as an item that could match an empty string. This meant that an
1055        enclosing group might also not be so recognized, causing infinite looping
1056        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1057        with the subject "ab", where knowledge that the repeated group can match
1058        nothing is needed in order to break the loop.
1060    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1061        exec(), but without supplying a callout function, matching went wrong.
1063    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1064        leak if the size of the offset vector was greater than 30. When the vector
1065        is smaller, the saved offsets during recursion go onto a local stack
1066        vector, but for larger vectors malloc() is used. It was failing to free
1067        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1068        error, in fact).
1070    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1071        heapframe that is used only when UTF-8 support is enabled. This caused no
1072        problem, but was untidy.
1074    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1075        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1076        included within another project.
1078    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1079        slightly modified by me:
1081          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1082              not building pcregrep.
1084          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1085              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1087    25. Forward references, both numeric and by name, in patterns that made use of
1088        duplicate group numbers, could behave incorrectly or give incorrect errors,
1089        because when scanning forward to find the reference group, PCRE was not
1090        taking into account the duplicate group numbers. A pattern such as
1091        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1093    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1094        the feature of a custom pointer more persuasive (as requested by a user).
1096    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1097        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1098        pre-defined.
1100    28. Added support for (*UTF8) at the start of a pattern.
1102    29. Arrange for flags added by the "release type" setting in CMake to be shown
1103        in the configuration summary.
1106  Version 7.8 05-Sep-08  Version 7.8 05-Sep-08
1107  ---------------------  ---------------------

Removed from v.377  
changed lines
  Added in v.738

  ViewVC Help
Powered by ViewVC 1.1.5