/[pcre]/code/trunk/ChangeLog
ViewVC logotype

Diff of /code/trunk/ChangeLog

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

revision 277 by ph10, Mon Nov 26 17:03:45 2007 UTC revision 1319 by ph10, Wed May 1 16:03:57 2013 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.5 12-Nov-07  Version 8.33 28-April-2013
5    --------------------------
6    
7    1.  Added 'U' to some constants that are compared to unsigned integers, to
8        avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
9        variables that are added to signed variables, to ensure the result is
10        signed and can be negated.
11    
12    2.  Applied patch by Daniel Richard G for quashing MSVC warnings to the
13        CMake config files.
14    
15    3.  Revise the creation of config.h.generic so that all boolean macros are
16        #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
17        overriding via -D on the command line possible.
18    
19    4.  Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
20        to unsigned int is reported to make a quite noticeable speed difference in
21        a specific Windows environment. Testing on Linux did also appear to show
22        some benefit (and it is clearly not harmful). Also fixed the definition of
23        Xop which should be unsigned.
24    
25    5.  Related to (4), changing the definition of the intermediate variable cc
26        in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
27        improvements.
28    
29    6.  Fix forward search in JIT when link size is 3 or greater. Also removed some
30        unnecessary spaces.
31    
32    7.  Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
33        and later.
34    
35    8.  Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
36    
37    9.  Optimizing fast_forward_start_bits in JIT.
38    
39    10. Adding experimental support for callouts in JIT, and fixing some
40        issues revealed during this work. Namely:
41    
42        (a) Unoptimized capturing brackets incorrectly reset on backtrack.
43    
44        (b) Minimum length was not checked before the matching is started.
45    
46    11. The value of capture_last that is passed to callouts was incorrect in some
47        cases when there was a capture on one path that was subsequently abandoned
48        after a backtrack. Also, the capture_last value is now reset after a
49        recursion, since all captures are also reset in this case.
50    
51    12. The interpreter no longer returns the "too many substrings" error in the
52        case when an overflowing capture is in a branch that is subsequently
53        abandoned after a backtrack.
54    
55    13. In the pathological case when an offset vector of size 2 is used, pcretest
56        now prints out the matched string after a yield of 0 or 1.
57    
58    14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
59        Only supported by the JIT compiler at the moment.
60    
61    15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
62    
63    16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
64        offset of the starting point of the matching process, provided the offsets
65        vector is large enough.
66    
67    17. The \A escape now records a lookbehind value of 1, though its execution
68        does not actually inspect the previous character. This is to ensure that,
69        in partial multi-segment matching, at least one character from the old
70        segment is retained when a new segment is processed. Otherwise, if there
71        are no lookbehinds in the pattern, \A might match incorrectly at the start
72        of a new segment.
73    
74    18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
75    
76    19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
77        gives some modest performance improvement in 8-bit mode.
78    
79    20. Added the PCRE-specific property \p{Xuc} for matching characters that can
80        be expressed in certain programming languages using Universal Character
81        Names.
82    
83    21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
84        which points out that "non characters" are not "characters that may not
85        appear in Unicode strings" but rather "characters that are reserved for
86        internal use and have only local meaning".
87    
88    22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
89        there was a conditional group that depended on an assertion, if the
90        assertion was false, the callout that immediately followed the alternation
91        in the condition was skipped when pcre_exec() was used for matching.
92    
93    23. Allow an explicit callout to be inserted before an assertion that is the
94        condition for a conditional group, for compatibility with automatic
95        callouts, which always insert a callout at this point.
96    
97    24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
98        confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
99    
100    25. (*PRUNE) is now supported by the JIT compiler.
101    
102    26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
103    
104    27. Fix the case where there are two or more SKIPs with arguments that may be
105        ignored.
106    
107    28. (*SKIP) is now supported by the JIT compiler.
108    
109    29. (*THEN) is now supported by the JIT compiler.
110    
111    30. Update RunTest with additional test selector options.
112    
113    31. The way PCRE handles backtracking verbs has been changed in two ways.
114    
115        (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
116        SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
117        backtracking. In some cases this makes it more Perl-compatible, but Perl's
118        rather obscure rules do not always do the same thing.
119    
120        (2) Previously, backtracking verbs were confined within assertions. This is
121        no longer the case for positive assertions, except for (*ACCEPT). Again,
122        this sometimes improves Perl compatibility, and sometimes does not.
123    
124    32. A number of tests that were in test 2 because Perl did things differently
125        have been moved to test 1, because either Perl or PCRE has changed, and
126        these tests are now compatible.
127    
128    32. Control verbs are handled in the same way in JIT and interpreter.
129    
130    33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
131        contained a forward subroutine reference caused a compile error.
132    
133    34. Auto-detect and optimize limited repetitions in JIT.
134    
135    35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
136        blocking (*UTF) etc.
137    
138    36. In the interpreter, maximizing pattern repetitions for characters and
139        character types now use tail recursion, which reduces stack usage.
140    
141    37. The value of the max lookbehind was not correctly preserved if a compiled
142        and saved regex was reloaded on a host of different endianness.
143    
144    38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
145        of the compiled pattern block, expand the flags field from 16 to 32 bits
146        because it was almost full.
147    
148    
149    Version 8.32 30-November-2012
150    -----------------------------
151    
152    1.  Improved JIT compiler optimizations for first character search and single
153        character iterators.
154    
155    2.  Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
156        Patch by Daniel Richard G.
157    
158    3.  Single character iterator optimizations in the JIT compiler.
159    
160    4.  Improved JIT compiler optimizations for character ranges.
161    
162    5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
163        Reported by Giuseppe D'Angelo.
164    
165    6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
166        of a line, was being set incorrectly in cases where .* appeared inside
167        atomic brackets at the start of a pattern, or where there was a subsequent
168        *PRUNE or *SKIP.
169    
170    7.  Improved instruction cache flush for POWER/PowerPC.
171        Patch by Daniel Richard G.
172    
173    8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
174        grep:
175    
176        (a) There is now no limit to the number of patterns to be matched.
177    
178        (b) An error is given if a pattern is too long.
179    
180        (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
181            are now supported.
182    
183        (d) --exclude-from and --include-from (multiple use) have been added.
184    
185        (e) Exclusions and inclusions now apply to all files and directories, not
186            just to those obtained from scanning a directory recursively.
187    
188        (f) Multiple uses of -f and --file-list are now supported.
189    
190        (g) In a Windows environment, the default for -d has been changed from
191            "read" (the GNU grep default) to "skip", because otherwise the presence
192            of a directory in the file list provokes an error.
193    
194        (h) The documentation has been revised and clarified in places.
195    
196    9.  Improve the matching speed of capturing brackets.
197    
198    10. Changed the meaning of \X so that it now matches a Unicode extended
199        grapheme cluster.
200    
201    11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
202        out POSIX threads when JIT support is configured.
203    
204    12. Added support for PCRE_STUDY_EXTRA_NEEDED.
205    
206    13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
207        structure could go wrong in environments where size_t is not the same size
208        as int.
209    
210    14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
211        set.
212    
213    15. The EBCDIC support had decayed; later updates to the code had included
214        explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
215        general tidy up of EBCDIC-related issues, and the documentation was also
216        not quite right. There is now a test that can be run on ASCII systems to
217        check some of the EBCDIC-related things (but is it not a full test).
218    
219    16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
220        in a small tidy to the code.
221    
222    17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
223    
224    18. If the --only-matching (-o) option in pcregrep is specified multiple
225        times, each one causes appropriate output. For example, -o1 -o2 outputs the
226        substrings matched by the 1st and 2nd capturing parentheses. A separating
227        string can be specified by --om-separator (default empty).
228    
229    19. Improving the first n character searches.
230    
231    20. Turn case lists for horizontal and vertical white space into macros so that
232        they are defined only once.
233    
234    21. This set of changes together give more compatible Unicode case-folding
235        behaviour for characters that have more than one other case when UCP
236        support is available.
237    
238        (a) The Unicode property table now has offsets into a new table of sets of
239            three or more characters that are case-equivalent. The MultiStage2.py
240            script that generates these tables (the pcre_ucd.c file) now scans
241            CaseFolding.txt instead of UnicodeData.txt for character case
242            information.
243    
244        (b) The code for adding characters or ranges of characters to a character
245            class has been abstracted into a generalized function that also handles
246            case-independence. In UTF-mode with UCP support, this uses the new data
247            to handle characters with more than one other case.
248    
249        (c) A bug that is fixed as a result of (b) is that codepoints less than 256
250            whose other case is greater than 256 are now correctly matched
251            caselessly. Previously, the high codepoint matched the low one, but not
252            vice versa.
253    
254        (d) The processing of \h, \H, \v, and \ in character classes now makes use
255            of the new class addition function, using character lists defined as
256            macros alongside the case definitions of 20 above.
257    
258        (e) Caseless back references now work with characters that have more than
259            one other case.
260    
261        (f) General caseless matching of characters with more than one other case
262            is supported.
263    
264    22. Unicode character properties were updated from Unicode 6.2.0
265    
266    23. Improved CMake support under Windows. Patch by Daniel Richard G.
267    
268    24. Add support for 32-bit character strings, and UTF-32
269    
270    25. Major JIT compiler update (code refactoring and bugfixing).
271        Experimental Sparc 32 support is added.
272    
273    26. Applied a modified version of Daniel Richard G's patch to create
274        pcre.h.generic and config.h.generic by "make" instead of in the
275        PrepareRelease script.
276    
277    27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
278        pcre_compile.c when checking for a zero character.
279    
280    28. Introducing a native interface for JIT. Through this interface, the compiled
281        machine code can be directly executed. The purpose of this interface is to
282        provide fast pattern matching, so several sanity checks are not performed.
283        However, feature tests are still performed. The new interface provides
284        1.4x speedup compared to the old one.
285    
286    29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
287        the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
288        was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
289    
290    30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
291        greater than 0x7fffffff (which cannot be represented in UTF-8, even under
292        the "old" RFC 2279). Instead, it ended up passing a negative length to
293        pcre_exec().
294    
295    31. Add support for GCC's visibility feature to hide internal functions.
296    
297    32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
298        "unknown -C option" after outputting 0 or 1.
299    
300    33. There is now support for generating a code coverage report for the test
301        suite in environments where gcc is the compiler and lcov is installed. This
302        is mainly for the benefit of the developers.
303    
304    34. If PCRE is built with --enable-valgrind, certain memory regions are marked
305        unaddressable using valgrind annotations, allowing valgrind to detect
306        invalid memory accesses. This is mainly for the benefit of the developers.
307    
308    25. (*UTF) can now be used to start a pattern in any of the three libraries.
309    
310    26. Give configure error if --enable-cpp but no C++ compiler found.
311    
312    
313    Version 8.31 06-July-2012
314    -------------------------
315    
316    1.  Fixing a wrong JIT test case and some compiler warnings.
317    
318    2.  Removed a bashism from the RunTest script.
319    
320    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
321        to unsigned type, result still unsigned" that was given by an MS compiler
322        on encountering the code "-sizeof(xxx)".
323    
324    4.  Partial matching support is added to the JIT compiler.
325    
326    5.  Fixed several bugs concerned with partial matching of items that consist
327        of more than one character:
328    
329        (a) /^(..)\1/ did not partially match "aba" because checking references was
330            done on an "all or nothing" basis. This also applied to repeated
331            references.
332    
333        (b) \R did not give a hard partial match if \r was found at the end of the
334            subject.
335    
336        (c) \X did not give a hard partial match after matching one or more
337            characters at the end of the subject.
338    
339        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
340            a partial match for the string "\r".
341    
342        (e) When newline was set to CRLF, the metacharacter "." did not recognize
343            a partial match for a CR character at the end of the subject string.
344    
345    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
346        running pcretest, the text "(JIT)" added to the output whenever JIT is
347        actually used to run the match.
348    
349    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
350        or /S+[+] with a digit between 1 and 7.
351    
352    8.  OP_NOT now supports any UTF character not just single-byte ones.
353    
354    9.  (*MARK) control verb is now supported by the JIT compiler.
355    
356    10. The command "./RunTest list" lists the available tests without actually
357        running any of them. (Because I keep forgetting what they all are.)
358    
359    11. Add PCRE_INFO_MAXLOOKBEHIND.
360    
361    12. Applied a (slightly modified) user-supplied patch that improves performance
362        when the heap is used for recursion (compiled with --disable-stack-for-
363        recursion). Instead of malloc and free for each heap frame each time a
364        logical recursion happens, frames are retained on a chain and re-used where
365        possible. This sometimes gives as much as 30% improvement.
366    
367    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
368        call.
369    
370    14. As documented, (*COMMIT) is now confined to within a positive assertion.
371    
372    15. It is now possible to link pcretest with libedit as an alternative to
373        libreadline.
374    
375    16. (*COMMIT) control verb is now supported by the JIT compiler.
376    
377    17. The Unicode data tables have been updated to Unicode 6.1.0.
378    
379    18. Added --file-list option to pcregrep.
380    
381    19. Added binary file support to pcregrep, including the -a, --binary-files,
382        -I, and --text options.
383    
384    20. The madvise function is renamed for posix_madvise for QNX compatibility
385        reasons. Fixed by Giuseppe D'Angelo.
386    
387    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
388    
389    22. Changed the option for creating symbolic links for 16-bit man pages from
390        -s to -sf so that re-installing does not cause issues.
391    
392    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
393    
394    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
395        matches in certain environments (the workspace was not being correctly
396        retained). Also added to pcre_dfa_exec() a simple plausibility check on
397        some of the workspace data at the beginning of a restart.
398    
399    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
400        was not doing so when it should - probably a typo introduced by SVN 528
401        (change 8.10/14).
402    
403    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
404        \w+ when the character tables indicated that \x{c4} was a word character.
405        There were several related cases, all because the tests for doing a table
406        lookup were testing for characters less than 127 instead of 255.
407    
408    27. If a pattern contains capturing parentheses that are not used in a match,
409        their slots in the ovector are set to -1. For those that are higher than
410        any matched groups, this happens at the end of processing. In the case when
411        there were back references that the ovector was too small to contain
412        (causing temporary malloc'd memory to be used during matching), and the
413        highest capturing number was not used, memory off the end of the ovector
414        was incorrectly being set to -1. (It was using the size of the temporary
415        memory instead of the true size.)
416    
417    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
418        ovector size, it uses memory at the end of the block that it has got.
419    
420    29. Check for an overlong MARK name and give an error at compile time. The
421        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
422    
423    30. JIT compiler update.
424    
425    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
426        Rill for the patch.
427    
428    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
429    
430    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
431    
432    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
433        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
434        was enabled.
435    
436    35. Improve JIT code generation for greedy plus quantifier.
437    
438    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
439        1 to "aa" instead of to an empty string. The bug affected repeated groups
440        that could potentially match an empty string.
441    
442    37. Optimizing single character iterators in JIT.
443    
444    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
445        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
446        codepoints that are too big for the mode are faulted, and in a UTF mode,
447        disallowed codepoints are also faulted.
448    
449    39. If PCRE was compiled with UTF support, in three places in the DFA
450        matcher there was code that should only have been obeyed in UTF mode, but
451        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
452        processing when bytes with values greater than 127 were present. In 16-bit
453        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
454        both cases the values are those that cannot be the first data item in a UTF
455        character. The three items that might have provoked this were recursions,
456        possessively repeated groups, and atomic groups.
457    
458    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
459        and pcregrep, because some OS require shared objects to be explicitly
460        passed to ld, causing the link step to fail if they are not.
461    
462    41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
463        mode, patterns that started with \h* or \R* might be incorrectly matched.
464    
465    
466    Version 8.30 04-February-2012
467    -----------------------------
468    
469    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
470        name is defined in ctype.h.
471    
472    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
473        only in quite long subpatterns.
474    
475    3.  Removed the function pcre_info(), which has been obsolete and deprecated
476        since it was replaced by pcre_fullinfo() in February 2000.
477    
478    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
479        match a (*MARK), and the match failed at the start of the subject, a
480        reference to memory before the start of the subject could occur. This bug
481        was introduced by fix 17 of release 8.21.
482    
483    5.  A reference to an unset group with zero minimum repetition was giving
484        totally wrong answers (in non-JavaScript-compatibility mode). For example,
485        /(another)?(\1?)test/ matched against "hello world test". This bug was
486        introduced in release 8.13.
487    
488    6.  Add support for 16-bit character strings (a large amount of work involving
489        many changes and refactorings).
490    
491    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
492        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
493        from a file.
494    
495    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
496        rounding is not applied in this particular case).
497    
498    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
499        if they appear, or are escaped, in patterns.
500    
501    10. Get rid of a number of -Wunused-but-set-variable warnings.
502    
503    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
504        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
505        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
506        also returns the mark "x". This bug applied to capturing parentheses,
507        non-capturing parentheses, and atomic parentheses. It also applied to some
508        assertions.
509    
510    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
511        information out of configure.ac instead of relying on pcre.h.generic, which
512        is not stored in the repository.
513    
514    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
515        -lreadline.
516    
517    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
518    
519    15. Applied Graycode's patch to put the top-level frame on the stack rather
520        than the heap when not using the stack for recursion. This gives a
521        performance improvement in many cases when recursion is not deep.
522    
523    16. Experimental code added to "pcretest -C" to output the stack frame size.
524    
525    
526    Version 8.21 12-Dec-2011
527    ------------------------
528    
529    1.  Updating the JIT compiler.
530    
531    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
532        are added as well.
533    
534    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
535        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
536        calling _pcre_jit_exec. Some extra comments are added.
537    
538    4.  (*MARK) settings inside atomic groups that do not contain any capturing
539        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
540        was introduced by change 18 for 8.20.
541    
542    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
543        ECMA-262 standard.
544    
545    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
546        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
547        This bug was probably introduced by change 9 of 8.13.
548    
549    7.  While fixing 6 above, I noticed that a number of other items were being
550        incorrectly rejected as "not fixed length". This arose partly because newer
551        opcodes had not been added to the fixed-length checking code. I have (a)
552        corrected the bug and added tests for these items, and (b) arranged for an
553        error to occur if an unknown opcode is encountered while checking for fixed
554        length instead of just assuming "not fixed length". The items that were
555        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
556        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
557        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
558    
559    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
560        being incorrectly compiled and would have given unpredicatble results.
561    
562    9.  A possessively repeated subpattern with minimum repeat count greater than
563        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
564        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
565        the first (A) could occur when it should not.
566    
567    10. Add a cast and remove a redundant test from the code.
568    
569    11. JIT should use pcre_malloc/pcre_free for allocation.
570    
571    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
572        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
573        is anything other than /usr, -L is still shown).
574    
575    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
576    
577    14. Perl does not support \N without a following name in a [] class; PCRE now
578        also gives an error.
579    
580    15. If a forward reference was repeated with an upper limit of around 2000,
581        it caused the error "internal error: overran compiling workspace". The
582        maximum number of forward references (including repeats) was limited by the
583        internal workspace, and dependent on the LINK_SIZE. The code has been
584        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
585        the default depends on LINK_SIZE. There is a new upper limit (for safety)
586        of around 200,000 forward references. While doing this, I also speeded up
587        the filling in of repeated forward references.
588    
589    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
590        incorrectly expecting the subject to contain another "a" after the start.
591    
592    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
593        in the match, the SKIP should be ignored. This was not happening; instead
594        the SKIP was being treated as NOMATCH. For patterns such as
595        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
596        tested.
597    
598    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
599        now much more compatible with Perl, in particular in cases where the result
600        is a non-match for a non-anchored pattern. For example, if
601        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
602        "m", where previously it did not return a name. A side effect of this
603        change is that for partial matches, the last encountered mark name is
604        returned, as for non matches. A number of tests that were previously not
605        Perl-compatible have been moved into the Perl-compatible test files. The
606        refactoring has had the pleasing side effect of removing one argument from
607        the match() function, thus reducing its stack requirements.
608    
609    19. If the /S+ option was used in pcretest to study a pattern using JIT,
610        subsequent uses of /S (without +) incorrectly behaved like /S+.
611    
612    21. Retrieve executable code size support for the JIT compiler and fixing
613        some warnings.
614    
615    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
616        not work when the shorter character appeared right at the end of the
617        subject string.
618    
619    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
620        systems.
621    
622    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
623        output it when the /M option is used in pcretest.
624    
625    25. The CheckMan script was not being included in the distribution. Also, added
626        an explicit "perl" to run Perl scripts from the PrepareRelease script
627        because this is reportedly needed in Windows.
628    
629    26. If study data was being save in a file and studying had not found a set of
630        "starts with" bytes for the pattern, the data written to the file (though
631        never used) was taken from uninitialized memory and so caused valgrind to
632        complain.
633    
634    27. Updated RunTest.bat as provided by Sheri Pierce.
635    
636    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
637    
638    29. Computation of memory usage for the table of capturing group names was
639        giving an unnecessarily large value.
640    
641    
642    Version 8.20 21-Oct-2011
643    ------------------------
644    
645    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
646        a POSIX class. After further experiments with Perl, which convinced me that
647        Perl has bugs and confusions, a closing square bracket is no longer allowed
648        in a POSIX name. This bug also affected patterns with classes that started
649        with full stops.
650    
651    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
652        captured substring, but while checking the failing first alternative,
653        substring 1 is temporarily captured. If the output vector supplied to
654        pcre_exec() was not big enough for this capture, the yield of the function
655        was still zero ("insufficient space for captured substrings"). This cannot
656        be totally fixed without adding another stack variable, which seems a lot
657        of expense for a edge case. However, I have improved the situation in cases
658        such as /(a)(b)x|abc/ matched against "abc", where the return code
659        indicates that fewer than the maximum number of slots in the ovector have
660        been set.
661    
662    3.  Related to (2) above: when there are more back references in a pattern than
663        slots in the output vector, pcre_exec() uses temporary memory during
664        matching, and copies in the captures as far as possible afterwards. It was
665        using the entire output vector, but this conflicts with the specification
666        that only 2/3 is used for passing back captured substrings. Now it uses
667        only the first 2/3, for compatibility. This is, of course, another edge
668        case.
669    
670    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
671        main code base, and can be used by building with --enable-jit. When this is
672        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
673        runtime --no-jit option is given.
674    
675    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
676        ovector, the return from the function was zero, implying that there were
677        other matches that did not fit. The correct "exactly full" value is now
678        returned.
679    
680    6.  If a subpattern that was called recursively or as a subroutine contained
681        (*PRUNE) or any other control that caused it to give a non-standard return,
682        invalid errors such as "Error -26 (nested recursion at the same subject
683        position)" or even infinite loops could occur.
684    
685    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
686        computing the minimum length on reaching *ACCEPT, and so ended up with the
687        wrong value of 1 rather than 0. Further investigation indicates that
688        computing a minimum subject length in the presence of *ACCEPT is difficult
689        (think back references, subroutine calls), and so I have changed the code
690        so that no minimum is registered for a pattern that contains *ACCEPT.
691    
692    8.  If (*THEN) was present in the first (true) branch of a conditional group,
693        it was not handled as intended. [But see 16 below.]
694    
695    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
696        Sheri Pierce.
697    
698    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
699        the first byte in a match must be "a".
700    
701    11. Change 17 for 8.13 increased the recursion depth for patterns like
702        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
703        pattern contains any instances of (*THEN). If it does not, the old
704        optimizations are restored. It would be nice to do this on a per-group
705        basis, but at the moment that is not feasible.
706    
707    12. In some environments, the output of pcretest -C is CRLF terminated. This
708        broke RunTest's code that checks for the link size. A single white space
709        character after the value is now allowed for.
710    
711    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
712        For "fr", it uses the Windows-specific input and output files.
713    
714    14. If (*THEN) appeared in a group that was called recursively or as a
715        subroutine, it did not work as intended. [But see next item.]
716    
717    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
718        pattern fragments (but not containing any | characters). If A and B are
719        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
720        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
721        D. In other words, Perl considers parentheses that do not contain any |
722        characters to be part of a surrounding alternative, whereas PCRE was
723        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
724        differently. PCRE now behaves in the same way as Perl, except in the case
725        of subroutine/recursion calls such as (?1) which have in any case always
726        been different (but PCRE had them first :-).
727    
728    16. Related to 15 above: Perl does not treat the | in a conditional group as
729        creating alternatives. Such a group is treated in the same way as an
730        ordinary group without any | characters when processing (*THEN). PCRE has
731        been changed to match Perl's behaviour.
732    
733    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
734        RunGrepTest script failed.
735    
736    18. Change 22 for version 13 caused atomic groups to use more stack. This is
737        inevitable for groups that contain captures, but it can lead to a lot of
738        stack use in large patterns. The old behaviour has been restored for atomic
739        groups that do not contain any capturing parentheses.
740    
741    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
742        suppress the check for a minimum subject length at run time. (If it was
743        given to pcre_exec() or pcre_dfa_exec() it did work.)
744    
745    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
746        fail to work when decoding hex characters in data strings in EBCDIC
747        environments.
748    
749    21. It appears that in at least one Mac OS environment, the isxdigit() function
750        is implemented as a macro that evaluates to its argument more than once,
751        contravening the C 90 Standard (I haven't checked a later standard). There
752        was an instance in pcretest which caused it to go wrong when processing
753        \x{...} escapes in subject strings. The has been rewritten to avoid using
754        things like p++ in the argument of isxdigit().
755    
756    
757    Version 8.13 16-Aug-2011
758    ------------------------
759    
760    1.  The Unicode data tables have been updated to Unicode 6.0.0.
761    
762    2.  Two minor typos in pcre_internal.h have been fixed.
763    
764    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
765        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
766        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
767    
768    4.  There were a number of related bugs in the code for matching backrefences
769        caselessly in UTF-8 mode when codes for the characters concerned were
770        different numbers of bytes. For example, U+023A and U+2C65 are an upper
771        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
772        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
773        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
774        2-byte code at the end of the subject (it thought there wasn't enough data
775        left).
776    
777    5.  Comprehensive information about what went wrong is now returned by
778        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
779        as the output vector has at least 2 elements. The offset of the start of
780        the failing character and a reason code are placed in the vector.
781    
782    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
783        now returned is for the first byte of the failing character, instead of the
784        last byte inspected. This is an incompatible change, but I hope it is small
785        enough not to be a problem. It makes the returned offset consistent with
786        pcre_exec() and pcre_dfa_exec().
787    
788    7.  pcretest now gives a text phrase as well as the error number when
789        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
790        failure, the offset and reason code are output.
791    
792    8.  When \R was used with a maximizing quantifier it failed to skip backwards
793        over a \r\n pair if the subsequent match failed. Instead, it just skipped
794        back over a single character (\n). This seems wrong (because it treated the
795        two characters as a single entity when going forwards), conflicts with the
796        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
797        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
798        has been changed.
799    
800    9.  Some internal refactoring has changed the processing so that the handling
801        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
802        time (the PCRE_DOTALL option was changed this way some time ago: version
803        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
804        which was always a bit of a fudge. It also means that there is one less
805        argument for the match() function, which reduces its stack requirements
806        slightly. This change also fixes an incompatibility with Perl: the pattern
807        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
808    
809    10. More internal refactoring has drastically reduced the number of recursive
810        calls to match() for possessively repeated groups such as (abc)++ when
811        using pcre_exec().
812    
813    11. While implementing 10, a number of bugs in the handling of groups were
814        discovered and fixed:
815    
816        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
817        (a|)*(?1) gave a compile-time internal error.
818        ((a|)+)+  did not notice that the outer group could match an empty string.
819        (^a|^)+   was not marked as anchored.
820        (.*a|.*)+ was not marked as matching at start or after a newline.
821    
822    12. Yet more internal refactoring has removed another argument from the match()
823        function. Special calls to this function are now indicated by setting a
824        value in a variable in the "match data" data block.
825    
826    13. Be more explicit in pcre_study() instead of relying on "default" for
827        opcodes that mean there is no starting character; this means that when new
828        ones are added and accidentally left out of pcre_study(), testing should
829        pick them up.
830    
831    14. The -s option of pcretest has been documented for ages as being an old
832        synonym of -m (show memory usage). I have changed it to mean "force study
833        for every regex", that is, assume /S for every regex. This is similar to -i
834        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
835        using it. It makes it easier to run collections of tests with and without
836        study enabled, and thereby test pcre_study() more easily. All the standard
837        tests are now run with and without -s (but some patterns can be marked as
838        "never study" - see 20 below).
839    
840    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
841        restoration of the capturing data to the outer values was not happening
842        correctly.
843    
844    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
845        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
846        pattern had matched an empty string, and so incorrectly returned a no
847        match.
848    
849    17. There was optimizing code for the last branch of non-capturing parentheses,
850        and also for the obeyed branch of a conditional subexpression, which used
851        tail recursion to cut down on stack usage. Unfortunately, now that there is
852        the possibility of (*THEN) occurring in these branches, tail recursion is
853        no longer possible because the return has to be checked for (*THEN). These
854        two optimizations have therefore been removed. [But see 8.20/11 above.]
855    
856    18. If a pattern containing \R was studied, it was assumed that \R always
857        matched two bytes, thus causing the minimum subject length to be
858        incorrectly computed because \R can also match just one byte.
859    
860    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
861        was incorrectly computed.
862    
863    20. If /S is present twice on a test pattern in pcretest input, it now
864        *disables* studying, thereby overriding the use of -s on the command line
865        (see 14 above). This is necessary for one or two tests to keep the output
866        identical in both cases.
867    
868    21. When (*ACCEPT) was used in an assertion that matched an empty string and
869        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
870    
871    22. When an atomic group that contained a capturing parenthesis was
872        successfully matched, but the branch in which it appeared failed, the
873        capturing was not being forgotten if a higher numbered group was later
874        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
875        group 1 to "a", when in fact it should be unset. This applied to multi-
876        branched capturing and non-capturing groups, repeated or not, and also to
877        positive assertions (capturing in negative assertions does not happen
878        in PCRE) and also to nested atomic groups.
879    
880    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
881        subject after a captured substring, to make it easier to tell which of a
882        number of identical substrings has been captured.
883    
884    24. The way atomic groups are processed by pcre_exec() has been changed so that
885        if they are repeated, backtracking one repetition now resets captured
886        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
887        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
888        "aaa". Previously, it would have been "a". As part of this code
889        refactoring, the way recursive calls are handled has also been changed.
890    
891    25. If an assertion condition captured any substrings, they were not passed
892        back unless some other capturing happened later. For example, if
893        (?(?=(a))a) was matched against "a", no capturing was returned.
894    
895    26. When studying a pattern that contained subroutine calls or assertions,
896        the code for finding the minimum length of a possible match was handling
897        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
898        group 1 called group 2 while simultaneously a separate group 2 called group
899        1). A stack overflow occurred in this case. I have fixed this by limiting
900        the recursion depth to 10.
901    
902    27. Updated RunTest.bat in the distribution to the version supplied by Tom
903        Fortmann. This supports explicit test numbers on the command line, and has
904        argument validation and error reporting.
905    
906    28. An instance of \X with an unlimited repeat could fail if at any point the
907        first character it looked at was a mark character.
908    
909    29. Some minor code refactoring concerning Unicode properties and scripts
910        should reduce the stack requirement of match() slightly.
911    
912    30. Added the '=' option to pcretest to check the setting of unused capturing
913        slots at the end of the pattern, which are documented as being -1, but are
914        not included in the return count.
915    
916    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
917        compiled something random. Now it gives a compile-time error (as does
918        Perl).
919    
920    32. A *MARK encountered during the processing of a positive assertion is now
921        recorded and passed back (compatible with Perl).
922    
923    33. If --only-matching or --colour was set on a pcregrep call whose pattern
924        had alternative anchored branches, the search for a second match in a line
925        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
926        matched the line "0102" twice. The same bug affected patterns that started
927        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
928        twice.
929    
930    34. Previously, PCRE did not allow quantification of assertions. However, Perl
931        does, and because of capturing effects, quantifying parenthesized
932        assertions may at times be useful. Quantifiers are now allowed for
933        parenthesized assertions.
934    
935    35. A minor code tidy in pcre_compile() when checking options for \R usage.
936    
937    36. \g was being checked for fancy things in a character class, when it should
938        just be a literal "g".
939    
940    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
941        appearance of a nested POSIX class supersedes an apparent external class.
942        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
943        unescaped square brackets may also appear as part of class names. For
944        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
945        more like Perl. (But see 8.20/1 above.)
946    
947    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
948        was because it thought it was \N{name}, which is not supported).
949    
950    39. Add minix to OS list not supporting the -S option in pcretest.
951    
952    40. PCRE tries to detect cases of infinite recursion at compile time, but it
953        cannot analyze patterns in sufficient detail to catch mutual recursions
954        such as ((?1))((?2)). There is now a runtime test that gives an error if a
955        subgroup is called recursively as a subpattern for a second time at the
956        same position in the subject string. In previous releases this might have
957        been caught by the recursion limit, or it might have run out of stack.
958    
959    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
960        happen only once. PCRE was, however incorrectly giving a compile time error
961        "recursive call could loop indefinitely" because it cannot analyze the
962        pattern in sufficient detail. The compile time test no longer happens when
963        PCRE is compiling a conditional subpattern, but actual runaway loops are
964        now caught at runtime (see 40 above).
965    
966    42. It seems that Perl allows any characters other than a closing parenthesis
967        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
968        has been changed to be the same.
969    
970    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
971        as not to get warnings when autogen.sh is called. Also changed
972        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
973    
974    44. To help people who use pcregrep to scan files containing exceedingly long
975        lines, the following changes have been made:
976    
977        (a) The default value of the buffer size parameter has been increased from
978            8K to 20K. (The actual buffer used is three times this size.)
979    
980        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
981            PCRE is built.
982    
983        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
984            to be set at run time.
985    
986        (d) Numerical values in pcregrep options can be followed by K or M, for
987            example --buffer-size=50K.
988    
989        (e) If a line being scanned overflows pcregrep's buffer, an error is now
990            given and the return code is set to 2.
991    
992    45. Add a pointer to the latest mark to the callout data block.
993    
994    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
995        partial match of an empty string instead of no match. This was specific to
996        the use of ".".
997    
998    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
999        complete match instead of a partial match. This bug was dependent on both
1000        the PCRE_UTF8 and PCRE_DOTALL options being set.
1001    
1002    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
1003        starting byte set, because \b was not being ignored.
1004    
1005    
1006    Version 8.12 15-Jan-2011
1007    ------------------------
1008    
1009    1.  Fixed some typos in the markup of the man pages, and wrote a script that
1010        checks for such things as part of the documentation building process.
1011    
1012    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
1013        --match-limit and --recursion-limit options (added for 8.11). In
1014        particular, this made one of the standard tests fail. (The integer value
1015        went into the wrong half of a long int.)
1016    
1017    3.  If the --colour option was given to pcregrep with -v (invert match), it
1018        did strange things, either producing crazy output, or crashing. It should,
1019        of course, ignore a request for colour when reporting lines that do not
1020        match.
1021    
1022    4.  Another pcregrep bug caused similar problems if --colour was specified with
1023        -M (multiline) and the pattern match finished with a line ending.
1024    
1025    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
1026        matched in multiline mode, the following line was shown as part of the
1027        match. This seems wrong, so I have changed it.
1028    
1029    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
1030        the check for further matches in the same line (so they could be coloured)
1031        to overrun the end of the current line. If another match was found, it was
1032        incorrectly shown (and then shown again when found in the next line).
1033    
1034    7.  If pcregrep was compiled under Windows, there was a reference to the
1035        function pcregrep_exit() before it was defined. I am assuming this was
1036        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
1037        reported by a user. I've moved the definition above the reference.
1038    
1039    
1040    Version 8.11 10-Dec-2010
1041    ------------------------
1042    
1043    1.  (*THEN) was not working properly if there were untried alternatives prior
1044        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
1045        backtracked to try for "b" instead of moving to the next alternative branch
1046        at the same level (in this case, to look for "c"). The Perl documentation
1047        is clear that when (*THEN) is backtracked onto, it goes to the "next
1048        alternative in the innermost enclosing group".
1049    
1050    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
1051        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
1052        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
1053        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
1054        (*THEN).
1055    
1056    3.  If \s appeared in a character class, it removed the VT character from
1057        the class, even if it had been included by some previous item, for example
1058        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
1059        of \s, but is part of the POSIX "space" class.)
1060    
1061    4.  A partial match never returns an empty string (because you can always
1062        match an empty string at the end of the subject); however the checking for
1063        an empty string was starting at the "start of match" point. This has been
1064        changed to the "earliest inspected character" point, because the returned
1065        data for a partial match starts at this character. This means that, for
1066        example, /(?<=abc)def/ gives a partial match for the subject "abc"
1067        (previously it gave "no match").
1068    
1069    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
1070        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
1071        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
1072        has an implication that the given string is incomplete (because a partial
1073        match is preferred over a full match). For this reason, these items now
1074        give a partial match in this situation. [Aside: previously, the one case
1075        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
1076        match rather than a full match, which was wrong by the old rules, but is
1077        now correct.]
1078    
1079    6.  There was a bug in the handling of #-introduced comments, recognized when
1080        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
1081        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
1082        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
1083        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
1084        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
1085        places in pcre_compile().
1086    
1087    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
1088        comments when looking ahead for named forward references to subpatterns,
1089        the only newline sequence it recognized was NL. It now handles newlines
1090        according to the set newline convention.
1091    
1092    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
1093        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
1094        cater for a lack of strerror(). These oversights have been fixed.
1095    
1096    9.  Added --match-limit and --recursion-limit to pcregrep.
1097    
1098    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
1099    
1100    11. When the -o option was used, pcregrep was setting a return code of 1, even
1101        when matches were found, and --line-buffered was not being honoured.
1102    
1103    12. Added an optional parentheses number to the -o and --only-matching options
1104        of pcregrep.
1105    
1106    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
1107        can match an empty string. The code to do it in pcretest and pcredemo
1108        needed fixing:
1109    
1110        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
1111            only one byte after an empty string match just before CRLF (this case
1112            just got forgotten; "any" and "anycrlf" were OK).
1113    
1114        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
1115            mode when an empty string match preceded an ASCII character followed by
1116            a non-ASCII character. (The code for advancing by one character rather
1117            than one byte was nonsense.)
1118    
1119        (c) The pcredemo.c sample program did not have any code at all to handle
1120            the cases when CRLF is a valid newline sequence.
1121    
1122    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
1123        as a starting offset was within the subject string. There is now a new
1124        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
1125        negative or greater than the length of the string. In order to test this,
1126        pcretest is extended to allow the setting of negative starting offsets.
1127    
1128    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
1129        starting offset points to the beginning of a UTF-8 character was
1130        unnecessarily clumsy. I tidied it up.
1131    
1132    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
1133        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
1134    
1135    17. Nobody had reported that the --include_dir option, which was added in
1136        release 7.7 should have been called --include-dir (hyphen, not underscore)
1137        for compatibility with GNU grep. I have changed it to --include-dir, but
1138        left --include_dir as an undocumented synonym, and the same for
1139        --exclude-dir, though that is not available in GNU grep, at least as of
1140        release 2.5.4.
1141    
1142    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
1143        characters from a string of bytes) have been redefined so as not to use
1144        loops, in order to improve performance in some environments. At the same
1145        time, I abstracted some of the common code into auxiliary macros to save
1146        repetition (this should not affect the compiled code).
1147    
1148    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
1149        compile-time error is now given if \c is not followed by an ASCII
1150        character, that is, a byte less than 128. (In EBCDIC mode, the code is
1151        different, and any byte value is allowed.)
1152    
1153    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
1154        START_OPTIMIZE option, which is now allowed at compile time - but just
1155        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
1156        to pcregrep and other applications that have no direct access to PCRE
1157        options. The new /Y option in pcretest sets this option when calling
1158        pcre_compile().
1159    
1160    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
1161        back references. Groups containing recursive back references were forced to
1162        be atomic by that change, but in the case of named groups, the amount of
1163        memory required was incorrectly computed, leading to "Failed: internal
1164        error: code overflow". This has been fixed.
1165    
1166    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
1167        pcretest.c, to avoid build problems in some Borland environments.
1168    
1169    
1170    Version 8.10 25-Jun-2010
1171    ------------------------
1172    
1173    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
1174        THEN.
1175    
1176    2.  (*ACCEPT) was not working when inside an atomic group.
1177    
1178    3.  Inside a character class, \B is treated as a literal by default, but
1179        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
1180        causes the error). The code is unchanged, but I tidied the documentation.
1181    
1182    4.  Inside a character class, PCRE always treated \R and \X as literals,
1183        whereas Perl faults them if its -w option is set. I have changed PCRE so
1184        that it faults them when PCRE_EXTRA is set.
1185    
1186    5.  Added support for \N, which always matches any character other than
1187        newline. (It is the same as "." when PCRE_DOTALL is not set.)
1188    
1189    6.  When compiling pcregrep with newer versions of gcc which may have
1190        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
1191        declared with attribute warn_unused_result" were given. Just casting the
1192        result to (void) does not stop the warnings; a more elaborate fudge is
1193        needed. I've used a macro to implement this.
1194    
1195    7.  Minor change to pcretest.c to avoid a compiler warning.
1196    
1197    8.  Added four artifical Unicode properties to help with an option to make
1198        \s etc use properties (see next item). The new properties are: Xan
1199        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
1200    
1201    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
1202        use Unicode properties. (*UCP) at the start of a pattern can be used to set
1203        this option. Modified pcretest to add /W to test this facility. Added
1204        REG_UCP to make it available via the POSIX interface.
1205    
1206    10. Added --line-buffered to pcregrep.
1207    
1208    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
1209        studied, and the match started with a letter with a code point greater than
1210        127 whose first byte was different to the first byte of the other case of
1211        the letter, the other case of this starting letter was not recognized
1212        (#976).
1213    
1214    12. If a pattern that was studied started with a repeated Unicode property
1215        test, for example, \p{Nd}+, there was the theoretical possibility of
1216        setting up an incorrect bitmap of starting bytes, but fortunately it could
1217        not have actually happened in practice until change 8 above was made (it
1218        added property types that matched character-matching opcodes).
1219    
1220    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
1221        possible starting bytes for non-anchored patterns.
1222    
1223    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
1224        \R, and also a number of cases that involve Unicode properties, both
1225        explicit and implicit when PCRE_UCP is set.
1226    
1227    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
1228        input, it could crash or give wrong results if characters with values
1229        greater than 0xc0 were present in the subject string. (Detail: it assumed
1230        UTF-8 input when processing these items.)
1231    
1232    16. Added a lot of (int) casts to avoid compiler warnings in systems where
1233        size_t is 64-bit (#991).
1234    
1235    17. Added a check for running out of memory when PCRE is compiled with
1236        --disable-stack-for-recursion (#990).
1237    
1238    18. If the last data line in a file for pcretest does not have a newline on
1239        the end, a newline was missing in the output.
1240    
1241    19. The default pcre_chartables.c file recognizes only ASCII characters (values
1242        less than 128) in its various bitmaps. However, there is a facility for
1243        generating tables according to the current locale when PCRE is compiled. It
1244        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
1245        characters, are recognized by isspace() and therefore were getting set in
1246        these tables, and indeed these tables seem to approximate to ISO 8859. This
1247        caused a problem in UTF-8 mode when pcre_study() was used to create a list
1248        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
1249        which of course cannot start UTF-8 characters. I have changed the code so
1250        that only real ASCII characters (less than 128) and the correct starting
1251        bytes for UTF-8 encodings are set for characters greater than 127 when in
1252        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
1253        altogether.)
1254    
1255    20. Added the /T option to pcretest so as to be able to run tests with non-
1256        standard character tables, thus making it possible to include the tests
1257        used for 19 above in the standard set of tests.
1258    
1259    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
1260        reference to a subpattern the other side of a comment that contains an
1261        opening parenthesis caused either an internal compiling error, or a
1262        reference to the wrong subpattern.
1263    
1264    
1265    Version 8.02 19-Mar-2010
1266    ------------------------
1267    
1268    1.  The Unicode data tables have been updated to Unicode 5.2.0.
1269    
1270    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
1271        configured.
1272    
1273    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
1274        original author of that file, following a query about its status.
1275    
1276    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
1277        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
1278    
1279    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
1280        quantifier applied to a forward-referencing subroutine call, could compile
1281        incorrect code or give the error "internal error: previously-checked
1282        referenced subpattern not found".
1283    
1284    6.  Both MS Visual Studio and Symbian OS have problems with initializing
1285        variables to point to external functions. For these systems, therefore,
1286        pcre_malloc etc. are now initialized to local functions that call the
1287        relevant global functions.
1288    
1289    7.  There were two entries missing in the vectors called coptable and poptable
1290        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
1291        I've fixed the data, and added a kludgy way of testing at compile time that
1292        the lengths are correct (equal to the number of opcodes).
1293    
1294    8.  Following on from 7, I added a similar kludge to check the length of the
1295        eint vector in pcreposix.c.
1296    
1297    9.  Error texts for pcre_compile() are held as one long string to avoid too
1298        much relocation at load time. To find a text, the string is searched,
1299        counting zeros. There was no check for running off the end of the string,
1300        which could happen if a new error number was added without updating the
1301        string.
1302    
1303    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
1304    
1305    11. \K was not working if it appeared in an atomic group or in a group that
1306        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
1307        \K is "not well defined" if used in an assertion. PCRE now accepts it if
1308        the assertion is positive, but not if it is negative.
1309    
1310    12. Change 11 fortuitously reduced the size of the stack frame used in the
1311        "match()" function of pcre_exec.c by one pointer. Forthcoming
1312        implementation of support for (*MARK) will need an extra pointer on the
1313        stack; I have reserved it now, so that the stack frame size does not
1314        decrease.
1315    
1316    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
1317        item in branch that calls a recursion is a subroutine call - as in the
1318        second branch in the above example - was incorrectly given the compile-
1319        time error "recursive call could loop indefinitely" because pcre_compile()
1320        was not correctly checking the subroutine for matching a non-empty string.
1321    
1322    14. The checks for overrunning compiling workspace could trigger after an
1323        overrun had occurred. This is a "should never occur" error, but it can be
1324        triggered by pathological patterns such as hundreds of nested parentheses.
1325        The checks now trigger 100 bytes before the end of the workspace.
1326    
1327    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
1328    
1329    
1330    Version 8.01 19-Jan-2010
1331    ------------------------
1332    
1333    1.  If a pattern contained a conditional subpattern with only one branch (in
1334        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
1335        computed the wrong minimum data length (which is of course zero for such
1336        subpatterns). This could cause incorrect "no match" results.
1337    
1338    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
1339        the pattern is reset in the first branch, pcre_compile() failed with
1340        "internal error: code overflow at offset...". This happened only when
1341        the reset was to the original external option setting. (An optimization
1342        abstracts leading options settings into an external setting, which was the
1343        cause of this.)
1344    
1345    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
1346        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
1347        assertion pattern did not match (meaning that the assertion was true), it
1348        was incorrectly treated as false if the SKIP had been reached during the
1349        matching. This also applied to assertions used as conditions.
1350    
1351    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
1352        assertion subpattern, including such a pattern used as a condition,
1353        unpredictable results occurred, instead of the error return
1354        PCRE_ERROR_DFA_UITEM.
1355    
1356    5.  The C++ GlobalReplace function was not working like Perl for the special
1357        situation when an empty string is matched. It now does the fancy magic
1358        stuff that is necessary.
1359    
1360    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
1361        removed. (These were left over from very, very early versions of PCRE.)
1362    
1363    7.  Some cosmetic changes to the code to make life easier when compiling it
1364        as part of something else:
1365    
1366        (a) Change DEBUG to PCRE_DEBUG.
1367    
1368        (b) In pcre_compile(), rename the member of the "branch_chain" structure
1369            called "current" as "current_branch", to prevent a collision with the
1370            Linux macro when compiled as a kernel module.
1371    
1372        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
1373            prevent a collision with the Linux macro when compiled as a kernel
1374            module.
1375    
1376    8.  In pcre_compile() there are some checks for integer overflows that used to
1377        cast potentially large values to (double). This has been changed to that
1378        when building, a check for int64_t is made, and if it is found, it is used
1379        instead, thus avoiding the use of floating point arithmetic. (There is no
1380        other use of FP in PCRE.) If int64_t is not found, the fallback is to
1381        double.
1382    
1383    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
1384        2005 (difference between two addresses compared to an unsigned value).
1385    
1386    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
1387        custom one, because of the following reported problem in Windows:
1388    
1389          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
1390              under Win32.
1391          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
1392              therefore missing the function definition.
1393          - The compiler thus generates a "C" signature for the test function.
1394          - The linker fails to find the "C" function.
1395          - PCRE fails to configure if asked to do so against libbz2.
1396    
1397    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
1398        messages were output:
1399    
1400          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
1401          rerunning libtoolize, to keep the correct libtool macros in-tree.
1402          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
1403    
1404        I have done both of these things.
1405    
1406    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
1407        most of the time, it *can* run out if it is given a pattern that contains a
1408        runaway infinite recursion. I updated the discussion in the pcrestack man
1409        page.
1410    
1411    13. Now that we have gone to the x.xx style of version numbers, the minor
1412        version may start with zero. Using 08 or 09 is a bad idea because users
1413        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
1414        interpreted as invalid octal numbers. I've updated the previous comment in
1415        configure.ac, and also added a check that gives an error if 08 or 09 are
1416        used.
1417    
1418    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
1419        causing partial matching to fail when the end of the subject matched \W
1420        in a UTF-8 pattern where \W was quantified with a minimum of 3.
1421    
1422    15. There were some discrepancies between the declarations in pcre_internal.h
1423        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
1424        their definitions. The declarations used "const uschar *" and the
1425        definitions used USPTR. Even though USPTR is normally defined as "const
1426        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
1427        reported that: "This difference in casting confuses some C++ compilers, for
1428        example, SunCC recognizes above declarations as different functions and
1429        generates broken code for hbpcre." I have changed the declarations to use
1430        USPTR.
1431    
1432    16. GNU libtool is named differently on some systems. The autogen.sh script now
1433        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
1434        (FreeBSD).
1435    
1436    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
1437        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
1438        comment: "Figure out how to create a longlong from a string: strtoll and
1439        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
1440        instance, but it only takes 2 args instead of 3!"
1441    
1442    18. A subtle bug concerned with back references has been fixed by a change of
1443        specification, with a corresponding code fix. A pattern such as
1444        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
1445        refers, was giving matches when it shouldn't. For example, xa=xaaa would
1446        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
1447        same bug. Such groups have to be quantified to be useful, or contained
1448        inside another quantified group. (If there's no repetition, the reference
1449        can never match.) The problem arises because, having left the group and
1450        moved on to the rest of the pattern, a later failure that backtracks into
1451        the group uses the captured value from the final iteration of the group
1452        rather than the correct earlier one. I have fixed this in PCRE by forcing
1453        any group that contains a reference to itself to be an atomic group; that
1454        is, there cannot be any backtracking into it once it has completed. This is
1455        similar to recursive and subroutine calls.
1456    
1457    
1458    Version 8.00 19-Oct-09
1459    ----------------------
1460    
1461    1.  The table for translating pcre_compile() error codes into POSIX error codes
1462        was out-of-date, and there was no check on the pcre_compile() error code
1463        being within the table. This could lead to an OK return being given in
1464        error.
1465    
1466    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
1467        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
1468        in a Windows environment.
1469    
1470    3.  The pcregrep --count option prints the count for each file even when it is
1471        zero, as does GNU grep. However, pcregrep was also printing all files when
1472        --files-with-matches was added. Now, when both options are given, it prints
1473        counts only for those files that have at least one match. (GNU grep just
1474        prints the file name in this circumstance, but including the count seems
1475        more useful - otherwise, why use --count?) Also ensured that the
1476        combination -clh just lists non-zero counts, with no names.
1477    
1478    4.  The long form of the pcregrep -F option was incorrectly implemented as
1479        --fixed_strings instead of --fixed-strings. This is an incompatible change,
1480        but it seems right to fix it, and I didn't think it was worth preserving
1481        the old behaviour.
1482    
1483    5.  The command line items --regex=pattern and --regexp=pattern were not
1484        recognized by pcregrep, which required --regex pattern or --regexp pattern
1485        (with a space rather than an '='). The man page documented the '=' forms,
1486        which are compatible with GNU grep; these now work.
1487    
1488    6.  No libpcreposix.pc file was created for pkg-config; there was just
1489        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
1490    
1491    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
1492        when UCP support is not needed, by modifying the Python script that
1493        generates it from Unicode data files. This should not matter if the module
1494        is correctly used as a library, but I received one complaint about 50K of
1495        unwanted data. My guess is that the person linked everything into his
1496        program rather than using a library. Anyway, it does no harm.
1497    
1498    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
1499        was a minimum greater than 1 for a wide character in a possessive
1500        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
1501        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
1502        character. Chaos in the form of incorrect output or a compiling loop could
1503        result.
1504    
1505    9.  The restrictions on what a pattern can contain when partial matching is
1506        requested for pcre_exec() have been removed. All patterns can now be
1507        partially matched by this function. In addition, if there are at least two
1508        slots in the offset vector, the offset of the earliest inspected character
1509        for the match and the offset of the end of the subject are set in them when
1510        PCRE_ERROR_PARTIAL is returned.
1511    
1512    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
1513        synonymous with PCRE_PARTIAL, for backwards compatibility, and
1514        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
1515        and may be more useful for multi-segment matching.
1516    
1517    11. Partial matching with pcre_exec() is now more intuitive. A partial match
1518        used to be given if ever the end of the subject was reached; now it is
1519        given only if matching could not proceed because another character was
1520        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
1521        string "Z", which now yields "no match" instead of "partial match". In the
1522        case of pcre_dfa_exec(), "no match" is given if every matching path for the
1523        final character ended with (*FAIL).
1524    
1525    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
1526        if the pattern had a "must contain" character that was already found in the
1527        earlier partial match, unless partial matching was again requested. For
1528        example, with the pattern /dog.(body)?/, the "must contain" character is
1529        "g". If the first part-match was for the string "dog", restarting with
1530        "sbody" failed. This bug has been fixed.
1531    
1532    13. The string returned by pcre_dfa_exec() after a partial match has been
1533        changed so that it starts at the first inspected character rather than the
1534        first character of the match. This makes a difference only if the pattern
1535        starts with a lookbehind assertion or \b or \B (\K is not supported by
1536        pcre_dfa_exec()). It's an incompatible change, but it makes the two
1537        matching functions compatible, and I think it's the right thing to do.
1538    
1539    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
1540        so that the demonstration program is easily available in environments where
1541        PCRE has not been installed from source.
1542    
1543    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
1544        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
1545        library.
1546    
1547    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
1548        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
1549        is not the first non-POSIX option to be added. Clearly some people find
1550        these options useful.
1551    
1552    17. If a caller to the POSIX matching function regexec() passes a non-zero
1553        value for nmatch with a NULL value for pmatch, the value of
1554        nmatch is forced to zero.
1555    
1556    18. RunGrepTest did not have a test for the availability of the -u option of
1557        the diff command, as RunTest does. It now checks in the same way as
1558        RunTest, and also checks for the -b option.
1559    
1560    19. If an odd number of negated classes containing just a single character
1561        interposed, within parentheses, between a forward reference to a named
1562        subpattern and the definition of the subpattern, compilation crashed with
1563        an internal error, complaining that it could not find the referenced
1564        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
1565        [The bug was that it was starting one character too far in when skipping
1566        over the character class, thus treating the ] as data rather than
1567        terminating the class. This meant it could skip too much.]
1568    
1569    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
1570        /g option in pcretest when the pattern contains \K, which makes it possible
1571        to have an empty string match not at the start, even when the pattern is
1572        anchored. Updated pcretest and pcredemo to use this option.
1573    
1574    21. If the maximum number of capturing subpatterns in a recursion was greater
1575        than the maximum at the outer level, the higher number was returned, but
1576        with unset values at the outer level. The correct (outer level) value is
1577        now given.
1578    
1579    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
1580        PCRE did not set those parentheses (unlike Perl). I have now found a way to
1581        make it do so. The string so far is captured, making this feature
1582        compatible with Perl.
1583    
1584    23. The tests have been re-organized, adding tests 11 and 12, to make it
1585        possible to check the Perl 5.10 features against Perl 5.10.
1586    
1587    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
1588        pattern matches a fixed length string. PCRE did not allow this; now it
1589        does. Neither allows recursion.
1590    
1591    25. I finally figured out how to implement a request to provide the minimum
1592        length of subject string that was needed in order to match a given pattern.
1593        (It was back references and recursion that I had previously got hung up
1594        on.) This code has now been added to pcre_study(); it finds a lower bound
1595        to the length of subject needed. It is not necessarily the greatest lower
1596        bound, but using it to avoid searching strings that are too short does give
1597        some useful speed-ups. The value is available to calling programs via
1598        pcre_fullinfo().
1599    
1600    26. While implementing 25, I discovered to my embarrassment that pcretest had
1601        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
1602        study optimizations had never been tested with that matching function.
1603        Oops. What is worse, even when it was passed study data, there was a bug in
1604        pcre_dfa_exec() that meant it never actually used it. Double oops. There
1605        were also very few tests of studied patterns with pcre_dfa_exec().
1606    
1607    27. If (?| is used to create subpatterns with duplicate numbers, they are now
1608        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
1609        on the other side of the coin, they are no longer allowed to have different
1610        names, because these cannot be distinguished in PCRE, and this has caused
1611        confusion. (This is a difference from Perl.)
1612    
1613    28. When duplicate subpattern names are present (necessarily with different
1614        numbers, as required by 27 above), and a test is made by name in a
1615        conditional pattern, either for a subpattern having been matched, or for
1616        recursion in such a pattern, all the associated numbered subpatterns are
1617        tested, and the overall condition is true if the condition is true for any
1618        one of them. This is the way Perl works, and is also more like the way
1619        testing by number works.
1620    
1621    
1622    Version 7.9 11-Apr-09
1623    ---------------------
1624    
1625    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
1626        (pcretest), all targets were linked against these libraries. This included
1627        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
1628        libraries. This caused unwanted dependencies to be created. This problem
1629        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
1630        pcretest is linked with readline.
1631    
1632    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
1633        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
1634        moved outside it again, because FALSE and TRUE are already defined in AIX,
1635        but BOOL is not.
1636    
1637    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
1638        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
1639    
1640    4.  The pcregrep documentation said spaces were inserted as well as colons (or
1641        hyphens) following file names and line numbers when outputting matching
1642        lines. This is not true; no spaces are inserted. I have also clarified the
1643        wording for the --colour (or --color) option.
1644    
1645    5.  In pcregrep, when --colour was used with -o, the list of matching strings
1646        was not coloured; this is different to GNU grep, so I have changed it to be
1647        the same.
1648    
1649    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
1650        each matching line was coloured. Now it goes on to look for further matches
1651        of any of the test patterns, which is the same behaviour as GNU grep.
1652    
1653    7.  A pattern that could match an empty string could cause pcregrep to loop; it
1654        doesn't make sense to accept an empty string match in pcregrep, so I have
1655        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
1656        seems to be how GNU grep behaves.
1657    
1658    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1659        start or after a newline", because the conditional assertion was not being
1660        correctly handled. The rule now is that both the assertion and what follows
1661        in the first alternative must satisfy the test.
1662    
1663    9.  If auto-callout was enabled in a pattern with a conditional group whose
1664        condition was an assertion, PCRE could crash during matching, both with
1665        pcre_exec() and pcre_dfa_exec().
1666    
1667    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1668        used for matching.
1669    
1670    11. Unicode property support in character classes was not working for
1671        characters (bytes) greater than 127 when not in UTF-8 mode.
1672    
1673    12. Added the -M command line option to pcretest.
1674    
1675    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1676    
1677    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1678    
1679    16. Added comments and documentation about mis-use of no_arg in the C++
1680        wrapper.
1681    
1682    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1683        from Martin Jerabek that uses macro names for all relevant character and
1684        string constants.
1685    
1686    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1687        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1688        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1689        these, but not everybody uses configure.
1690    
1691    19. A conditional group that had only one branch was not being correctly
1692        recognized as an item that could match an empty string. This meant that an
1693        enclosing group might also not be so recognized, causing infinite looping
1694        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1695        with the subject "ab", where knowledge that the repeated group can match
1696        nothing is needed in order to break the loop.
1697    
1698    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1699        exec(), but without supplying a callout function, matching went wrong.
1700    
1701    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1702        leak if the size of the offset vector was greater than 30. When the vector
1703        is smaller, the saved offsets during recursion go onto a local stack
1704        vector, but for larger vectors malloc() is used. It was failing to free
1705        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1706        error, in fact).
1707    
1708    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1709        heapframe that is used only when UTF-8 support is enabled. This caused no
1710        problem, but was untidy.
1711    
1712    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1713        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1714        included within another project.
1715    
1716    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1717        slightly modified by me:
1718    
1719          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1720              not building pcregrep.
1721    
1722          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1723              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1724    
1725    25. Forward references, both numeric and by name, in patterns that made use of
1726        duplicate group numbers, could behave incorrectly or give incorrect errors,
1727        because when scanning forward to find the reference group, PCRE was not
1728        taking into account the duplicate group numbers. A pattern such as
1729        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1730    
1731    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1732        the feature of a custom pointer more persuasive (as requested by a user).
1733    
1734    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1735        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1736        pre-defined.
1737    
1738    28. Added support for (*UTF8) at the start of a pattern.
1739    
1740    29. Arrange for flags added by the "release type" setting in CMake to be shown
1741        in the configuration summary.
1742    
1743    
1744    Version 7.8 05-Sep-08
1745    ---------------------
1746    
1747    1.  Replaced UCP searching code with optimized version as implemented for Ad
1748        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
1749        stage table and inline lookup instead of a function, giving speed ups of 2
1750        to 5 times on some simple patterns that I tested. Permission was given to
1751        distribute the MultiStage2.py script that generates the tables (it's not in
1752        the tarball, but is in the Subversion repository).
1753    
1754    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
1755        scripts.
1756    
1757    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
1758        a group with a zero qualifier. The result of the study could be incorrect,
1759        or the function might crash, depending on the pattern.
1760    
1761    4.  Caseless matching was not working for non-ASCII characters in back
1762        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
1763        It now works when Unicode Property Support is available.
1764    
1765    5.  In pcretest, an escape such as \x{de} in the data was always generating
1766        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
1767        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
1768        truncation.
1769    
1770    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
1771    
1772    7.  Added two (int) casts to pcregrep when printing the difference of two
1773        pointers, in case they are 64-bit values.
1774    
1775    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
1776        test 2 if it fails.
1777    
1778    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1779        and a #define of that name to empty if it is not externally set. This is to
1780        allow users of MSVC to set it if necessary.
1781    
1782    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1783        the convenience functions in the pcre_get.c source file.
1784    
1785    11. An option change at the start of a pattern that had top-level alternatives
1786        could cause overwriting and/or a crash. This command provoked a crash in
1787        some environments:
1788    
1789          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1790    
1791        This potential security problem was recorded as CVE-2008-2371.
1792    
1793    12. For a pattern where the match had to start at the beginning or immediately
1794        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1795        pcre_dfa_exec() could read past the end of the passed subject if there was
1796        no match. To help with detecting such bugs (e.g. with valgrind), I modified
1797        pcretest so that it places the subject at the end of its malloc-ed buffer.
1798    
1799    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
1800        exec() might read past the end of the data buffer in UTF-8 mode.
1801    
1802    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
1803        the data contained the byte 0x85 as part of a UTF-8 character within its
1804        first line. This applied both to normal and DFA matching.
1805    
1806    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
1807        /^[^d]*?$/8 failed to match "abc".
1808    
1809    16. Added a missing copyright notice to pcrecpp_internal.h.
1810    
1811    17. Make it more clear in the documentation that values returned from
1812        pcre_exec() in ovector are byte offsets, not character counts.
1813    
1814    18. Tidied a few places to stop certain compilers from issuing warnings.
1815    
1816    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
1817        supplied by Stefan Weber. I made a further small update for 7.8 because
1818        there is a change of source arrangements: the pcre_searchfuncs.c module is
1819        replaced by pcre_ucd.c.
1820    
1821    
1822    Version 7.7 07-May-08
1823    ---------------------
1824    
1825    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
1826        a string to a long long, pretend we don't even have a long long." This is
1827        done by checking for the strtoq, strtoll, and _strtoi64 functions.
1828    
1829    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
1830        pre-7.6 versions, which defined a global no_arg variable instead of putting
1831        it in the RE class. (See also #8 below.)
1832    
1833    3.  Remove a line of dead code, identified by coverity and reported by Nuno
1834        Lopes.
1835    
1836    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
1837    
1838        (1) The include/exclude patterns were being applied to the whole pathnames
1839            of files, instead of just to the final components.
1840    
1841        (2) If there was more than one level of directory, the subdirectories were
1842            skipped unless they satisfied the include/exclude conditions. This is
1843            inconsistent with GNU grep (and could even be seen as contrary to the
1844            pcregrep specification - which I improved to make it absolutely clear).
1845            The action now is always to scan all levels of directory, and just
1846            apply the include/exclude patterns to regular files.
1847    
1848    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
1849        --exclude_dir in the tests to avoid scanning .svn directories.
1850    
1851    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
1852        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
1853        doesn't support NULs in patterns.
1854    
1855    7.  Added some missing "const"s to declarations of static tables in
1856        pcre_compile.c and pcre_dfa_exec.c.
1857    
1858    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
1859        caused by fix #2  above. (Subsequently also a second patch to fix the
1860        first patch. And a third patch - this was a messy problem.)
1861    
1862    9.  Applied Craig's patch to remove the use of push_back().
1863    
1864    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
1865        matching function regexec().
1866    
1867    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
1868        which, however, unlike Perl's \g{...}, are subroutine calls, not back
1869        references. PCRE supports relative numbers with this syntax (I don't think
1870        Oniguruma does).
1871    
1872    12. Previously, a group with a zero repeat such as (...){0} was completely
1873        omitted from the compiled regex. However, this means that if the group
1874        was called as a subroutine from elsewhere in the pattern, things went wrong
1875        (an internal error was given). Such groups are now left in the compiled
1876        pattern, with a new opcode that causes them to be skipped at execution
1877        time.
1878    
1879    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
1880        to the way PCRE behaves:
1881    
1882        (a) A lone ] character is dis-allowed (Perl treats it as data).
1883    
1884        (b) A back reference to an unmatched subpattern matches an empty string
1885            (Perl fails the current match path).
1886    
1887        (c) A data ] in a character class must be notated as \] because if the
1888            first data character in a class is ], it defines an empty class. (In
1889            Perl it is not possible to have an empty class.) The empty class []
1890            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
1891            The negative empty class [^] matches any one character, independently
1892            of the DOTALL setting.
1893    
1894    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
1895        non-existent subpattern following a character class starting with ']' and
1896        containing () gave an internal compiling error instead of "reference to
1897        non-existent subpattern". Fortunately, when the pattern did exist, the
1898        compiled code was correct. (When scanning forwards to check for the
1899        existencd of the subpattern, it was treating the data ']' as terminating
1900        the class, so got the count wrong. When actually compiling, the reference
1901        was subsequently set up correctly.)
1902    
1903    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
1904        it was being rejected as not supported by pcre_dfa_exec(), even though
1905        other assertions are supported. I have made pcre_dfa_exec() support
1906        (*FAIL).
1907    
1908    16. The implementation of 13c above involved the invention of a new opcode,
1909        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
1910        cannot be changed at match time, I realized I could make a small
1911        improvement to matching performance by compiling OP_ALLANY instead of
1912        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1913        on the OP_ANY path.
1914    
1915    17. Compiling pcretest on Windows with readline support failed without the
1916        following two fixes: (1) Make the unistd.h include conditional on
1917        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1918    
1919    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1920        ncurses library to be included for pcretest when ReadLine support is
1921        requested, but also to allow for it to be overridden. This patch came from
1922        Daniel Bergström.
1923    
1924    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1925        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1926        any errors with the current Unicode tables. Thanks to Peter Kankowski for
1927        spotting this.
1928    
1929    
1930    Version 7.6 28-Jan-08
1931    ---------------------
1932    
1933    1.  A character class containing a very large number of characters with
1934        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
1935        overflow.
1936    
1937    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
1938        HAVE_LONG_LONG is not defined.
1939    
1940    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
1941        bring them up to date and include new features. This patch includes:
1942    
1943        - Fixed PH's badly added libz and libbz2 support.
1944        - Fixed a problem with static linking.
1945        - Added pcredemo. [But later removed - see 7 below.]
1946        - Fixed dftables problem and added an option.
1947        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
1948            HAVE_LONG_LONG.
1949        - Added readline support for pcretest.
1950        - Added an listing of the option settings after cmake has run.
1951    
1952    4.  A user submitted a patch to Makefile that makes it easy to create
1953        "pcre.dll" under mingw when using Configure/Make. I added stuff to
1954        Makefile.am that cause it to include this special target, without
1955        affecting anything else. Note that the same mingw target plus all
1956        the other distribution libraries and programs are now supported
1957        when configuring with CMake (see 6 below) instead of with
1958        Configure/Make.
1959    
1960    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
1961        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
1962        exported in the Windows port". It has not yet been confirmed that the patch
1963        solves the problem, but it does no harm.
1964    
1965    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
1966        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
1967        with CMake, and also correct the comment about stack recursion.
1968    
1969    7.  Remove the automatic building of pcredemo from the ./configure system and
1970        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
1971        of a program that users should build themselves after PCRE is installed, so
1972        building it automatically is not really right. What is more, it gave
1973        trouble in some build environments.
1974    
1975    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
1976    
1977    
1978    Version 7.5 10-Jan-08
1979  ---------------------  ---------------------
1980    
1981  1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'  1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
1982      values in parens when parsing an RE using the C++ wrapper."      values in parens when parsing an RE using the C++ wrapper."
1983    
1984  2.  Negative specials like \S did not work in character classes in UTF-8 mode.  2.  Negative specials like \S did not work in character classes in UTF-8 mode.
1985      Characters greater than 255 were excluded from the class instead of being      Characters greater than 255 were excluded from the class instead of being
1986      included.      included.
1987    
1988  3.  The same bug as (2) above applied to negated POSIX classes such as  3.  The same bug as (2) above applied to negated POSIX classes such as
1989      [:^space:].      [:^space:].
1990    
1991  4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it  4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1992      defined or documented. It seems to have been a typo for PCRE_STATIC, so      defined or documented. It seems to have been a typo for PCRE_STATIC, so
1993      I have changed it.      I have changed it.
1994    
1995  5.  The construct (?&) was not diagnosed as a syntax error (it referenced the  5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
1996      first named subpattern) and a construct such as (?&a) would reference the      first named subpattern) and a construct such as (?&a) would reference the
1997      first named subpattern whose name started with "a" (in other words, the      first named subpattern whose name started with "a" (in other words, the
1998      length check was missing). Both these problems are fixed. "Subpattern name      length check was missing). Both these problems are fixed. "Subpattern name
1999      expected" is now given for (?&) (a zero-length name), and this patch also      expected" is now given for (?&) (a zero-length name), and this patch also
2000      makes it give the same error for \k'' (previously it complained that that      makes it give the same error for \k'' (previously it complained that that
2001      was a reference to a non-existent subpattern).      was a reference to a non-existent subpattern).
2002    
2003  6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;  6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
2004      this is right because (?- can be followed by option settings as well as by      this is right because (?- can be followed by option settings as well as by
2005      digits. I have, however, made the messages clearer.      digits. I have, however, made the messages clearer.
2006    
2007  7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns  7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
2008      than the number used in the conditional) now cause a compile-time error.      than the number used in the conditional) now cause a compile-time error.
2009      This is actually not compatible with Perl, which accepts such patterns, but      This is actually not compatible with Perl, which accepts such patterns, but
2010      treats the conditional as always being FALSE (as PCRE used to), but it      treats the conditional as always being FALSE (as PCRE used to), but it
2011      seems to me that giving a diagnostic is better.      seems to me that giving a diagnostic is better.
2012    
2013  8.  Change "alphameric" to the more common word "alphanumeric" in comments  8.  Change "alphameric" to the more common word "alphanumeric" in comments
2014      and messages.      and messages.
2015    
2016  9.  Fix two occurrences of "backslash" in comments that should have been  9.  Fix two occurrences of "backslash" in comments that should have been
2017      "backspace".      "backspace".
2018    
2019  10. Remove two redundant lines of code that can never be obeyed (their function  10. Remove two redundant lines of code that can never be obeyed (their function
2020      was moved elsewhere).      was moved elsewhere).
2021    
2022  11. The program that makes PCRE's Unicode character property table had a bug  11. The program that makes PCRE's Unicode character property table had a bug
2023      which caused it to generate incorrect table entries for sequences of      which caused it to generate incorrect table entries for sequences of
2024      characters that have the same character type, but are in different scripts.      characters that have the same character type, but are in different scripts.
2025      It amalgamated them into a single range, with the script of the first of      It amalgamated them into a single range, with the script of the first of
2026      them. In other words, some characters were in the wrong script. There were      them. In other words, some characters were in the wrong script. There were
2027      thirteen such cases, affecting characters in the following ranges:      thirteen such cases, affecting characters in the following ranges:
2028    
2029        U+002b0 - U+002c1        U+002b0 - U+002c1
2030        U+0060c - U+0060d        U+0060c - U+0060d
2031        U+0061e - U+00612        U+0061e - U+00612
2032        U+0064b - U+0065e        U+0064b - U+0065e
2033        U+0074d - U+0076d        U+0074d - U+0076d
2034        U+01800 - U+01805        U+01800 - U+01805
# Line 66  Version 7.5 12-Nov-07 Line 2040  Version 7.5 12-Nov-07
2040        U+0fb46 - U+0fbb1        U+0fb46 - U+0fbb1
2041        U+10450 - U+1049d        U+10450 - U+1049d
2042    
2043    12. The -o option (show only the matching part of a line) for pcregrep was not
2044        compatible with GNU grep in that, if there was more than one match in a
2045        line, it showed only the first of them. It now behaves in the same way as
2046        GNU grep.
2047    
2048    13. If the -o and -v options were combined for pcregrep, it printed a blank
2049        line for every non-matching line. GNU grep prints nothing, and pcregrep now
2050        does the same. The return code can be used to tell if there were any
2051        non-matching lines.
2052    
2053    14. Added --file-offsets and --line-offsets to pcregrep.
2054    
2055    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
2056        infinitely looping recursion. The bug was that positive lookaheads were not
2057        being skipped when checking for a possible empty match (negative lookaheads
2058        and both kinds of lookbehind were skipped).
2059    
2060    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
2061        inclusion of <windows.h> to before rather than after the definition of
2062        INVALID_FILE_ATTRIBUTES (patch from David Byron).
2063    
2064    17. Specifying a possessive quantifier with a specific limit for a Unicode
2065        character property caused pcre_compile() to compile bad code, which led at
2066        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
2067        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
2068        caused the error; without that there was no problem.
2069    
2070    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
2071    
2072    19. Added --enable-pcretest-libreadline.
2073    
2074    20. In pcrecpp.cc, the variable 'count' was incremented twice in
2075        RE::GlobalReplace(). As a result, the number of replacements returned was
2076        double what it should be. I removed one of the increments, but Craig sent a
2077        later patch that removed the other one (the right fix) and added unit tests
2078        that check the return values (which was not done before).
2079    
2080    21. Several CMake things:
2081    
2082        (1) Arranged that, when cmake is used on Unix, the libraries end up with
2083            the names libpcre and libpcreposix, not just pcre and pcreposix.
2084    
2085        (2) The above change means that pcretest and pcregrep are now correctly
2086            linked with the newly-built libraries, not previously installed ones.
2087    
2088        (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
2089    
2090    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
2091        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
2092        UTF-8 newline character). The key issue is that the pattern starts .*;
2093        this means that the match must be either at the beginning, or after a
2094        newline. The bug was in the code for advancing after a failed match and
2095        checking that the new position followed a newline. It was not taking
2096        account of UTF-8 characters correctly.
2097    
2098    23. PCRE was behaving differently from Perl in the way it recognized POSIX
2099        character classes. PCRE was not treating the sequence [:...:] as a
2100        character class unless the ... were all letters. Perl, however, seems to
2101        allow any characters between [: and :], though of course it rejects as
2102        unknown any "names" that contain non-letters, because all the known class
2103        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
2104        for example, whereas PCRE did not - it did not recognize a POSIX character
2105        class. This seemed a bit dangerous, so the code has been changed to be
2106        closer to Perl. The behaviour is not identical to Perl, because PCRE will
2107        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
2108        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
2109        Perl does, and where it didn't before.
2110    
2111    24. Rewrite so as to remove the single use of %n from pcregrep because in some
2112        Windows environments %n is disabled by default.
2113    
2114    
2115  Version 7.4 21-Sep-07  Version 7.4 21-Sep-07
2116  ---------------------  ---------------------

Legend:
Removed from v.277  
changed lines
  Added in v.1319

  ViewVC Help
Powered by ViewVC 1.1.5