ViewVC logotype

Diff of /code/trunk/ChangeLog

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

revision 545 by ph10, Wed Jun 16 10:51:15 2010 UTC revision 784 by ph10, Mon Dec 5 12:33:44 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
4  Version 8.10 16-Jun-2010  Version 8.21 05-Dec-2011
5    ------------------------
7    1.  Updating the JIT compiler.
9    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
10        are added as well.
12    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
13        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
14        calling _pcre_jit_exec. Some extra comments are added.
16    4.  (*MARK) settings inside atomic groups that do not contain any capturing
17        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
18        was introduced by change 18 for 8.20.
20    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
21        ECMA-262 standard.
23    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
24        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
25        This bug was probably introduced by change 9 of 8.13.
27    7.  While fixing 6 above, I noticed that a number of other items were being
28        incorrectly rejected as "not fixed length". This arose partly because newer
29        opcodes had not been added to the fixed-length checking code. I have (a)
30        corrected the bug and added tests for these items, and (b) arranged for an
31        error to occur if an unknown opcode is encountered while checking for fixed
32        length instead of just assuming "not fixed length". The items that were
33        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
34        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
35        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
37    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
38        being incorrectly compiled and would have given unpredicatble results.
40    9.  A possessively repeated subpattern with minimum repeat count greater than
41        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
42        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
43        the first (A) could occur when it should not.
45    10. Add a cast and remove a redundant test from the code.
47    11. JIT should use pcre_malloc/pcre_free for allocation.
49    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
50        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
51        is anything other than /usr, -L is still shown).
53    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
55    14. Perl does not support \N without a following name in a [] class; PCRE now
56        also gives an error.
58    15. If a forward reference was repeated with an upper limit of around 2000,
59        it caused the error "internal error: overran compiling workspace". The
60        maximum number of forward references (including repeats) was limited by the
61        internal workspace, and dependent on the LINK_SIZE. The code has been
62        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
63        the default depends on LINK_SIZE. There is a new upper limit (for safety)
64        of around 200,000 forward references. While doing this, I also speeded up
65        the filling in of repeated forward references.
67    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
68        incorrectly expecting the subject to contain another "a" after the start.
70    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
71        in the match, the SKIP should be ignored. This was not happening; instead
72        the SKIP was being treated as NOMATCH. For patterns such as
73        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
74        tested.
76    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
77        now much more compatible with Perl, in particular in cases where the result
78        is a non-match for a non-anchored pattern. For example, if
79        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
80        "m", where previously it did not return a name. A side effect of this
81        change is that for partial matches, the last encountered mark name is
82        returned, as for non matches. A number of tests that were previously not
83        Perl-compatible have been moved into the Perl-compatible test files. The
84        refactoring has had the pleasing side effect of removing one argument from
85        the match() function, thus reducing its stack requirements.
87    19. If the /S+ option was used in pcretest to study a pattern using JIT,
88        subsequent uses of /S (without +) incorrectly behaved like /S+.
90    21. Retrieve executable code size support for the JIT compiler and fixing
91        some warnings.
93    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
94        not work when the shorter character appeared right at the end of the
95        subject string.
97    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
98        systems.
100    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
101        output it when the /M option is used in pcretest.
103    25. The CheckMan script was not being included in the distribution. Also, added
104        an explicit "perl" to run Perl scripts from the PrepareRelease script
105        because this is reportedly needed in Windows.
108    Version 8.20 21-Oct-2011
109    ------------------------
111    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
112        a POSIX class. After further experiments with Perl, which convinced me that
113        Perl has bugs and confusions, a closing square bracket is no longer allowed
114        in a POSIX name. This bug also affected patterns with classes that started
115        with full stops.
117    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
118        captured substring, but while checking the failing first alternative,
119        substring 1 is temporarily captured. If the output vector supplied to
120        pcre_exec() was not big enough for this capture, the yield of the function
121        was still zero ("insufficient space for captured substrings"). This cannot
122        be totally fixed without adding another stack variable, which seems a lot
123        of expense for a edge case. However, I have improved the situation in cases
124        such as /(a)(b)x|abc/ matched against "abc", where the return code
125        indicates that fewer than the maximum number of slots in the ovector have
126        been set.
128    3.  Related to (2) above: when there are more back references in a pattern than
129        slots in the output vector, pcre_exec() uses temporary memory during
130        matching, and copies in the captures as far as possible afterwards. It was
131        using the entire output vector, but this conflicts with the specification
132        that only 2/3 is used for passing back captured substrings. Now it uses
133        only the first 2/3, for compatibility. This is, of course, another edge
134        case.
136    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
137        main code base, and can be used by building with --enable-jit. When this is
138        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
139        runtime --no-jit option is given.
141    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
142        ovector, the return from the function was zero, implying that there were
143        other matches that did not fit. The correct "exactly full" value is now
144        returned.
146    6.  If a subpattern that was called recursively or as a subroutine contained
147        (*PRUNE) or any other control that caused it to give a non-standard return,
148        invalid errors such as "Error -26 (nested recursion at the same subject
149        position)" or even infinite loops could occur.
151    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
152        computing the minimum length on reaching *ACCEPT, and so ended up with the
153        wrong value of 1 rather than 0. Further investigation indicates that
154        computing a minimum subject length in the presence of *ACCEPT is difficult
155        (think back references, subroutine calls), and so I have changed the code
156        so that no minimum is registered for a pattern that contains *ACCEPT.
158    8.  If (*THEN) was present in the first (true) branch of a conditional group,
159        it was not handled as intended. [But see 16 below.]
161    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
162        Sheri Pierce.
164    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
165        the first byte in a match must be "a".
167    11. Change 17 for 8.13 increased the recursion depth for patterns like
168        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
169        pattern contains any instances of (*THEN). If it does not, the old
170        optimizations are restored. It would be nice to do this on a per-group
171        basis, but at the moment that is not feasible.
173    12. In some environments, the output of pcretest -C is CRLF terminated. This
174        broke RunTest's code that checks for the link size. A single white space
175        character after the value is now allowed for.
177    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
178        For "fr", it uses the Windows-specific input and output files.
180    14. If (*THEN) appeared in a group that was called recursively or as a
181        subroutine, it did not work as intended. [But see next item.]
183    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
184        pattern fragments (but not containing any | characters). If A and B are
185        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
186        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
187        D. In other words, Perl considers parentheses that do not contain any |
188        characters to be part of a surrounding alternative, whereas PCRE was
189        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
190        differently. PCRE now behaves in the same way as Perl, except in the case
191        of subroutine/recursion calls such as (?1) which have in any case always
192        been different (but PCRE had them first :-).
194    16. Related to 15 above: Perl does not treat the | in a conditional group as
195        creating alternatives. Such a group is treated in the same way as an
196        ordinary group without any | characters when processing (*THEN). PCRE has
197        been changed to match Perl's behaviour.
199    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
200        RunGrepTest script failed.
202    18. Change 22 for version 13 caused atomic groups to use more stack. This is
203        inevitable for groups that contain captures, but it can lead to a lot of
204        stack use in large patterns. The old behaviour has been restored for atomic
205        groups that do not contain any capturing parentheses.
207    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
208        suppress the check for a minimum subject length at run time. (If it was
209        given to pcre_exec() or pcre_dfa_exec() it did work.)
211    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
212        fail to work when decoding hex characters in data strings in EBCDIC
213        environments.
215    21. It appears that in at least one Mac OS environment, the isxdigit() function
216        is implemented as a macro that evaluates to its argument more than once,
217        contravening the C 90 Standard (I haven't checked a later standard). There
218        was an instance in pcretest which caused it to go wrong when processing
219        \x{...} escapes in subject strings. The has been rewritten to avoid using
220        things like p++ in the argument of isxdigit().
223    Version 8.13 16-Aug-2011
224    ------------------------
226    1.  The Unicode data tables have been updated to Unicode 6.0.0.
228    2.  Two minor typos in pcre_internal.h have been fixed.
230    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
231        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
232        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
234    4.  There were a number of related bugs in the code for matching backrefences
235        caselessly in UTF-8 mode when codes for the characters concerned were
236        different numbers of bytes. For example, U+023A and U+2C65 are an upper
237        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
238        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
239        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
240        2-byte code at the end of the subject (it thought there wasn't enough data
241        left).
243    5.  Comprehensive information about what went wrong is now returned by
244        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
245        as the output vector has at least 2 elements. The offset of the start of
246        the failing character and a reason code are placed in the vector.
248    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
249        now returned is for the first byte of the failing character, instead of the
250        last byte inspected. This is an incompatible change, but I hope it is small
251        enough not to be a problem. It makes the returned offset consistent with
252        pcre_exec() and pcre_dfa_exec().
254    7.  pcretest now gives a text phrase as well as the error number when
255        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
256        failure, the offset and reason code are output.
258    8.  When \R was used with a maximizing quantifier it failed to skip backwards
259        over a \r\n pair if the subsequent match failed. Instead, it just skipped
260        back over a single character (\n). This seems wrong (because it treated the
261        two characters as a single entity when going forwards), conflicts with the
262        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
263        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
264        has been changed.
266    9.  Some internal refactoring has changed the processing so that the handling
267        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
268        time (the PCRE_DOTALL option was changed this way some time ago: version
269        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
270        which was always a bit of a fudge. It also means that there is one less
271        argument for the match() function, which reduces its stack requirements
272        slightly. This change also fixes an incompatibility with Perl: the pattern
273        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
275    10. More internal refactoring has drastically reduced the number of recursive
276        calls to match() for possessively repeated groups such as (abc)++ when
277        using pcre_exec().
279    11. While implementing 10, a number of bugs in the handling of groups were
280        discovered and fixed:
282        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
283        (a|)*(?1) gave a compile-time internal error.
284        ((a|)+)+  did not notice that the outer group could match an empty string.
285        (^a|^)+   was not marked as anchored.
286        (.*a|.*)+ was not marked as matching at start or after a newline.
288    12. Yet more internal refactoring has removed another argument from the match()
289        function. Special calls to this function are now indicated by setting a
290        value in a variable in the "match data" data block.
292    13. Be more explicit in pcre_study() instead of relying on "default" for
293        opcodes that mean there is no starting character; this means that when new
294        ones are added and accidentally left out of pcre_study(), testing should
295        pick them up.
297    14. The -s option of pcretest has been documented for ages as being an old
298        synonym of -m (show memory usage). I have changed it to mean "force study
299        for every regex", that is, assume /S for every regex. This is similar to -i
300        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
301        using it. It makes it easier to run collections of tests with and without
302        study enabled, and thereby test pcre_study() more easily. All the standard
303        tests are now run with and without -s (but some patterns can be marked as
304        "never study" - see 20 below).
306    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
307        restoration of the capturing data to the outer values was not happening
308        correctly.
310    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
311        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
312        pattern had matched an empty string, and so incorrectly returned a no
313        match.
315    17. There was optimizing code for the last branch of non-capturing parentheses,
316        and also for the obeyed branch of a conditional subexpression, which used
317        tail recursion to cut down on stack usage. Unfortunately, now that there is
318        the possibility of (*THEN) occurring in these branches, tail recursion is
319        no longer possible because the return has to be checked for (*THEN). These
320        two optimizations have therefore been removed. [But see 8.20/11 above.]
322    18. If a pattern containing \R was studied, it was assumed that \R always
323        matched two bytes, thus causing the minimum subject length to be
324        incorrectly computed because \R can also match just one byte.
326    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
327        was incorrectly computed.
329    20. If /S is present twice on a test pattern in pcretest input, it now
330        *disables* studying, thereby overriding the use of -s on the command line
331        (see 14 above). This is necessary for one or two tests to keep the output
332        identical in both cases.
334    21. When (*ACCEPT) was used in an assertion that matched an empty string and
335        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
337    22. When an atomic group that contained a capturing parenthesis was
338        successfully matched, but the branch in which it appeared failed, the
339        capturing was not being forgotten if a higher numbered group was later
340        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
341        group 1 to "a", when in fact it should be unset. This applied to multi-
342        branched capturing and non-capturing groups, repeated or not, and also to
343        positive assertions (capturing in negative assertions does not happen
344        in PCRE) and also to nested atomic groups.
346    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
347        subject after a captured substring, to make it easier to tell which of a
348        number of identical substrings has been captured.
350    24. The way atomic groups are processed by pcre_exec() has been changed so that
351        if they are repeated, backtracking one repetition now resets captured
352        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
353        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
354        "aaa". Previously, it would have been "a". As part of this code
355        refactoring, the way recursive calls are handled has also been changed.
357    25. If an assertion condition captured any substrings, they were not passed
358        back unless some other capturing happened later. For example, if
359        (?(?=(a))a) was matched against "a", no capturing was returned.
361    26. When studying a pattern that contained subroutine calls or assertions,
362        the code for finding the minimum length of a possible match was handling
363        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
364        group 1 called group 2 while simultaneously a separate group 2 called group
365        1). A stack overflow occurred in this case. I have fixed this by limiting
366        the recursion depth to 10.
368    27. Updated RunTest.bat in the distribution to the version supplied by Tom
369        Fortmann. This supports explicit test numbers on the command line, and has
370        argument validation and error reporting.
372    28. An instance of \X with an unlimited repeat could fail if at any point the
373        first character it looked at was a mark character.
375    29. Some minor code refactoring concerning Unicode properties and scripts
376        should reduce the stack requirement of match() slightly.
378    30. Added the '=' option to pcretest to check the setting of unused capturing
379        slots at the end of the pattern, which are documented as being -1, but are
380        not included in the return count.
382    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
383        compiled something random. Now it gives a compile-time error (as does
384        Perl).
386    32. A *MARK encountered during the processing of a positive assertion is now
387        recorded and passed back (compatible with Perl).
389    33. If --only-matching or --colour was set on a pcregrep call whose pattern
390        had alternative anchored branches, the search for a second match in a line
391        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
392        matched the line "0102" twice. The same bug affected patterns that started
393        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
394        twice.
396    34. Previously, PCRE did not allow quantification of assertions. However, Perl
397        does, and because of capturing effects, quantifying parenthesized
398        assertions may at times be useful. Quantifiers are now allowed for
399        parenthesized assertions.
401    35. A minor code tidy in pcre_compile() when checking options for \R usage.
403    36. \g was being checked for fancy things in a character class, when it should
404        just be a literal "g".
406    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
407        appearance of a nested POSIX class supersedes an apparent external class.
408        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
409        unescaped square brackets may also appear as part of class names. For
410        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
411        more like Perl. (But see 8.20/1 above.)
413    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
414        was because it thought it was \N{name}, which is not supported).
416    39. Add minix to OS list not supporting the -S option in pcretest.
418    40. PCRE tries to detect cases of infinite recursion at compile time, but it
419        cannot analyze patterns in sufficient detail to catch mutual recursions
420        such as ((?1))((?2)). There is now a runtime test that gives an error if a
421        subgroup is called recursively as a subpattern for a second time at the
422        same position in the subject string. In previous releases this might have
423        been caught by the recursion limit, or it might have run out of stack.
425    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
426        happen only once. PCRE was, however incorrectly giving a compile time error
427        "recursive call could loop indefinitely" because it cannot analyze the
428        pattern in sufficient detail. The compile time test no longer happens when
429        PCRE is compiling a conditional subpattern, but actual runaway loops are
430        now caught at runtime (see 40 above).
432    42. It seems that Perl allows any characters other than a closing parenthesis
433        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
434        has been changed to be the same.
436    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
437        as not to get warnings when autogen.sh is called. Also changed
438        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
440    44. To help people who use pcregrep to scan files containing exceedingly long
441        lines, the following changes have been made:
443        (a) The default value of the buffer size parameter has been increased from
444            8K to 20K. (The actual buffer used is three times this size.)
446        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
447            PCRE is built.
449        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
450            to be set at run time.
452        (d) Numerical values in pcregrep options can be followed by K or M, for
453            example --buffer-size=50K.
455        (e) If a line being scanned overflows pcregrep's buffer, an error is now
456            given and the return code is set to 2.
458    45. Add a pointer to the latest mark to the callout data block.
460    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
461        partial match of an empty string instead of no match. This was specific to
462        the use of ".".
464    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
465        complete match instead of a partial match. This bug was dependent on both
466        the PCRE_UTF8 and PCRE_DOTALL options being set.
468    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
469        starting byte set, because \b was not being ignored.
472    Version 8.12 15-Jan-2011
473    ------------------------
475    1.  Fixed some typos in the markup of the man pages, and wrote a script that
476        checks for such things as part of the documentation building process.
478    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
479        --match-limit and --recursion-limit options (added for 8.11). In
480        particular, this made one of the standard tests fail. (The integer value
481        went into the wrong half of a long int.)
483    3.  If the --colour option was given to pcregrep with -v (invert match), it
484        did strange things, either producing crazy output, or crashing. It should,
485        of course, ignore a request for colour when reporting lines that do not
486        match.
488    4.  Another pcregrep bug caused similar problems if --colour was specified with
489        -M (multiline) and the pattern match finished with a line ending.
491    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
492        matched in multiline mode, the following line was shown as part of the
493        match. This seems wrong, so I have changed it.
495    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
496        the check for further matches in the same line (so they could be coloured)
497        to overrun the end of the current line. If another match was found, it was
498        incorrectly shown (and then shown again when found in the next line).
500    7.  If pcregrep was compiled under Windows, there was a reference to the
501        function pcregrep_exit() before it was defined. I am assuming this was
502        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
503        reported by a user. I've moved the definition above the reference.
506    Version 8.11 10-Dec-2010
507    ------------------------
509    1.  (*THEN) was not working properly if there were untried alternatives prior
510        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
511        backtracked to try for "b" instead of moving to the next alternative branch
512        at the same level (in this case, to look for "c"). The Perl documentation
513        is clear that when (*THEN) is backtracked onto, it goes to the "next
514        alternative in the innermost enclosing group".
516    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
517        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
518        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
519        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
520        (*THEN).
522    3.  If \s appeared in a character class, it removed the VT character from
523        the class, even if it had been included by some previous item, for example
524        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
525        of \s, but is part of the POSIX "space" class.)
527    4.  A partial match never returns an empty string (because you can always
528        match an empty string at the end of the subject); however the checking for
529        an empty string was starting at the "start of match" point. This has been
530        changed to the "earliest inspected character" point, because the returned
531        data for a partial match starts at this character. This means that, for
532        example, /(?<=abc)def/ gives a partial match for the subject "abc"
533        (previously it gave "no match").
535    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
536        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
537        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
538        has an implication that the given string is incomplete (because a partial
539        match is preferred over a full match). For this reason, these items now
540        give a partial match in this situation. [Aside: previously, the one case
541        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
542        match rather than a full match, which was wrong by the old rules, but is
543        now correct.]
545    6.  There was a bug in the handling of #-introduced comments, recognized when
546        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
547        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
548        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
549        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
550        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
551        places in pcre_compile().
553    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
554        comments when looking ahead for named forward references to subpatterns,
555        the only newline sequence it recognized was NL. It now handles newlines
556        according to the set newline convention.
558    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
559        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
560        cater for a lack of strerror(). These oversights have been fixed.
562    9.  Added --match-limit and --recursion-limit to pcregrep.
564    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
566    11. When the -o option was used, pcregrep was setting a return code of 1, even
567        when matches were found, and --line-buffered was not being honoured.
569    12. Added an optional parentheses number to the -o and --only-matching options
570        of pcregrep.
572    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
573        can match an empty string. The code to do it in pcretest and pcredemo
574        needed fixing:
576        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
577            only one byte after an empty string match just before CRLF (this case
578            just got forgotten; "any" and "anycrlf" were OK).
580        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
581            mode when an empty string match preceded an ASCII character followed by
582            a non-ASCII character. (The code for advancing by one character rather
583            than one byte was nonsense.)
585        (c) The pcredemo.c sample program did not have any code at all to handle
586            the cases when CRLF is a valid newline sequence.
588    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
589        as a starting offset was within the subject string. There is now a new
590        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
591        negative or greater than the length of the string. In order to test this,
592        pcretest is extended to allow the setting of negative starting offsets.
594    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
595        starting offset points to the beginning of a UTF-8 character was
596        unnecessarily clumsy. I tidied it up.
598    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
599        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
601    17. Nobody had reported that the --include_dir option, which was added in
602        release 7.7 should have been called --include-dir (hyphen, not underscore)
603        for compatibility with GNU grep. I have changed it to --include-dir, but
604        left --include_dir as an undocumented synonym, and the same for
605        --exclude-dir, though that is not available in GNU grep, at least as of
606        release 2.5.4.
608    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
609        characters from a string of bytes) have been redefined so as not to use
610        loops, in order to improve performance in some environments. At the same
611        time, I abstracted some of the common code into auxiliary macros to save
612        repetition (this should not affect the compiled code).
614    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
615        compile-time error is now given if \c is not followed by an ASCII
616        character, that is, a byte less than 128. (In EBCDIC mode, the code is
617        different, and any byte value is allowed.)
619    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
620        START_OPTIMIZE option, which is now allowed at compile time - but just
621        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
622        to pcregrep and other applications that have no direct access to PCRE
623        options. The new /Y option in pcretest sets this option when calling
624        pcre_compile().
626    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
627        back references. Groups containing recursive back references were forced to
628        be atomic by that change, but in the case of named groups, the amount of
629        memory required was incorrectly computed, leading to "Failed: internal
630        error: code overflow". This has been fixed.
632    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
633        pcretest.c, to avoid build problems in some Borland environments.
636    Version 8.10 25-Jun-2010
637  ------------------------  ------------------------
639  1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and  1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and

Removed from v.545  
changed lines
  Added in v.784

  ViewVC Help
Powered by ViewVC 1.1.5