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

Diff of /code/trunk/ChangeLog

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

revision 195 by ph10, Mon Jul 30 13:23:28 2007 UTC revision 1396 by ph10, Sun Nov 10 19:04:34 2013 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 7.3 05-Jul-07  Version 8.34 xx-xxxx-201x
5    --------------------------
6    
7    1.  Add pcre[16|32]_jit_free_unused_memory to forcibly free unused JIT
8        executable memory. Patch inspired by Carsten Klein.
9    
10    2.  ./configure --enable-coverage defined SUPPORT_GCOV in config.h, although
11        this macro is never tested and has no effect, because the work to support
12        coverage involves only compiling and linking options and special targets in
13        the Makefile. The comment in config.h implied that defining the macro would
14        enable coverage support, which is totally false. There was also support for
15        setting this macro in the CMake files (my fault, I just copied it from
16        configure). SUPPORT_GCOV has now been removed.
17    
18    3.  Make a small performance improvement in strlen16() and strlen32() in
19        pcretest.
20    
21    4.  Change 36 for 8.33 left some unreachable statements in pcre_exec.c,
22        detected by the Solaris compiler (gcc doesn't seem to be able to diagnose
23        these cases). There was also one in pcretest.c.
24    
25    5.  Cleaned up a "may be uninitialized" compiler warning in pcre_exec.c.
26    
27    6.  In UTF mode, the code for checking whether a group could match an empty
28        string (which is used for indefinitely repeated groups to allow for
29        breaking an infinite loop) was broken when the group contained a repeated
30        negated single-character class with a character that occupied more than one
31        data item and had a minimum repetition of zero (for example, [^\x{100}]* in
32        UTF-8 mode). The effect was undefined: the group might or might not be
33        deemed as matching an empty string, or the program might have crashed.
34    
35    7.  The code for checking whether a group could match an empty string was not
36        recognizing that \h, \H, \v, \V, and \R must match a character.
37    
38    8.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
39        an empty string. If it can, pcretest shows this in its information output.
40    
41    9.  Fixed two related bugs that applied to Unicode extended grapheme clusters
42        that were repeated with a maximizing qualifier (e.g. \X* or \X{2,5}) when
43        matched by pcre_exec() without using JIT:
44    
45        (a) If the rest of the pattern did not match after a maximal run of
46            grapheme clusters, the code for backing up to try with fewer of them
47            did not always back up over a full grapheme when characters that do not
48            have the modifier quality were involved, e.g. Hangul syllables.
49    
50        (b) If the match point in a subject started with modifier character, and
51            there was no match, the code could incorrectly back up beyond the match
52            point, and potentially beyond the first character in the subject,
53            leading to a segfault or an incorrect match result.
54    
55    10. A conditional group with an assertion condition could lead to PCRE
56        recording an incorrect first data item for a match if no other first data
57        item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
58        first data item, and therefore matched "ca" after "c" instead of at the
59        start.
60    
61    11. Change 40 for 8.33 (allowing pcregrep to find empty strings) showed up a
62        bug that caused the command "echo a | ./pcregrep -M '|a'" to loop.
63    
64    12. The source of pcregrep now includes z/OS-specific code so that it can be
65        compiled for z/OS as part of the special z/OS distribution.
66    
67    13. Added the -T and -TM options to pcretest.
68    
69    14. The code in pcre_compile.c for creating the table of named capturing groups
70        has been refactored. Instead of creating the table dynamically during the
71        actual compiling pass, the information is remembered during the pre-compile
72        pass (on the stack unless there are more than 20 named groups, in which
73        case malloc() is used) and the whole table is created before the actual
74        compile happens. This has simplified the code (it is now nearly 150 lines
75        shorter) and prepared the way for better handling of references to groups
76        with duplicate names.
77    
78    15. A back reference to a named subpattern when there is more than one of the
79        same name now checks them in the order in which they appear in the pattern.
80        The first one that is set is used for the reference. Previously only the
81        first one was inspected. This change makes PCRE more compatible with Perl.
82    
83    16. Unicode character properties were updated from Unicode 6.3.0.
84    
85    17. The compile-time code for auto-possessification has been refactored, based
86        on a patch by Zoltan Herczeg. It now happens after instead of during
87        compilation. The code is cleaner, and more cases are handled. The option
88        PCRE_NO_AUTO_POSSESSIFY is added for testing purposes, and the -O and /O
89        options in pcretest are provided to set it. It can also be set by
90        (*NO_AUTO_POSSESS) at the start of a pattern.
91    
92    18. The character VT has been added to the set of characters that match \s and
93        are generally treated as white space, following this same change in Perl
94        5.18. There is now no difference between "Perl space" and "POSIX space".
95    
96    19. The code for checking named groups as conditions, either for being set or
97        for being recursed, has been refactored (this is related to 14 and 15
98        above). Processing unduplicated named groups should now be as fast at
99        numerical groups, and processing duplicated groups should be faster than
100        before.
101    
102    20. Two patches to the CMake build system, by Alexander Barkov:
103    
104          (1) Replace the "source" command by "." in CMakeLists.txt because
105              "source" is a bash-ism.
106    
107          (2) Add missing HAVE_STDINT_H and HAVE_INTTYPES_H to config-cmake.h.in;
108              without these the CMake build does not work on Solaris.
109    
110    21. Perl has changed its handling of \8 and \9. If there is no previously
111        encountered capturing group of those numbers, they are treated as the
112        literal characters 8 and 9 instead of a binary zero followed by the
113        literals. PCRE now does the same.
114    
115    22. Following Perl, added \o{} to specify codepoints in octal, making it
116        possible to specify values greater than 0777 and also making them
117        unambiguous.
118    
119    23. Perl now gives an error for missing closing braces after \x{... instead of
120        treating the string as literal. PCRE now does the same.
121    
122    24. RunTest used to grumble if an inappropriate test was selected explicitly,
123        but just skip it when running all tests. This make it awkward to run ranges
124        of tests when one of them was inappropriate. Now it just skips any
125        inappropriate tests, as it always did when running all tests.
126    
127    25. If PCRE_AUTO_CALLOUT and PCRE_UCP were set for a pattern that contained
128        character types such as \d or \w, too many callouts were inserted, and the
129        data that they returned was rubbish.
130    
131    26. In UCP mode, \s was not matching two of the characters that Perl matches,
132        namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
133        were matched by \h. The code has now been refactored so that the lists of
134        the horizontal and vertical whitespace characters used for \h and \v (which
135        are defined only in one place) are now also used for \s.
136    
137    27. Add JIT support for the 64 bit TileGX architecture.
138        Patch by Jiong Wang (Tilera Corporation).
139    
140    28. Possessive quantifiers for classes (both explicit and automatically
141        generated) now use special opcodes instead of wrapping in ONCE brackets.
142    
143    29. Whereas an item such as A{4}+ ignored the possessivenes of the quantifier
144        (because it's meaningless), this was not happening when PCRE_CASELESS was
145        set. Not wrong, but inefficient.
146    
147    30. Updated perltest.pl to add /u (force Unicode mode) when /W (use Unicode
148        properties for \w, \d, etc) is present in a test regex. Otherwise if the
149        test contains no characters greater than 255, Perl doesn't realise it
150        should be using Unicode semantics.
151    
152    31. Upgraded the handling of the POSIX classes [:graph:], [:print:], and
153        [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
154        does in Unicode mode.
155    
156    32. Added the "forbid" facility to pcretest so that putting tests into the
157        wrong test files can sometimes be quickly detected.
158    
159    33. There is now a limit (default 250) on the depth of nesting of parentheses.
160        This limit is imposed to control the amount of system stack used at compile
161        time. It can be changed at build time by --with-parens-nest-limit=xxx or
162        the equivalent in CMake.
163    
164    34. Character classes such as [A-\d] or [a-[:digit:]] now cause compile-time
165        errors. Perl warns for these when in warning mode, but PCRE has no facility
166        for giving warnings.
167    
168    35. Change 34 for 8.13 allowed quantifiers on assertions, because Perl does.
169        However, this was not working for (?!) because it is optimized to (*FAIL),
170        for which PCRE does not allow quantifiers. The optimization is now disabled
171        when a quantifier follows (?!). I can't see any use for this, but it makes
172        things uniform.
173    
174    36. Perl no longer allows group names to start with digits, so I have made this
175        change also in PCRE. It simplifies the code a bit.
176    
177    37. In extended mode, Perl ignores spaces before a + that indicates a
178        possessive quantifier. PCRE allowed a space before the quantifier, but not
179        before the possessive +. It now does.
180    
181    
182    Version 8.33 28-May-2013
183    ------------------------
184    
185    1.  Added 'U' to some constants that are compared to unsigned integers, to
186        avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
187        variables that are added to signed variables, to ensure the result is
188        signed and can be negated.
189    
190    2.  Applied patch by Daniel Richard G for quashing MSVC warnings to the
191        CMake config files.
192    
193    3.  Revise the creation of config.h.generic so that all boolean macros are
194        #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
195        overriding via -D on the command line possible.
196    
197    4.  Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
198        to unsigned int is reported to make a quite noticeable speed difference in
199        a specific Windows environment. Testing on Linux did also appear to show
200        some benefit (and it is clearly not harmful). Also fixed the definition of
201        Xop which should be unsigned.
202    
203    5.  Related to (4), changing the definition of the intermediate variable cc
204        in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
205        improvements.
206    
207    6.  Fix forward search in JIT when link size is 3 or greater. Also removed some
208        unnecessary spaces.
209    
210    7.  Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
211        and later.
212    
213    8.  Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
214    
215    9.  Optimizing fast_forward_start_bits in JIT.
216    
217    10. Adding support for callouts in JIT, and fixing some issues revealed
218        during this work. Namely:
219    
220        (a) Unoptimized capturing brackets incorrectly reset on backtrack.
221    
222        (b) Minimum length was not checked before the matching is started.
223    
224    11. The value of capture_last that is passed to callouts was incorrect in some
225        cases when there was a capture on one path that was subsequently abandoned
226        after a backtrack. Also, the capture_last value is now reset after a
227        recursion, since all captures are also reset in this case.
228    
229    12. The interpreter no longer returns the "too many substrings" error in the
230        case when an overflowing capture is in a branch that is subsequently
231        abandoned after a backtrack.
232    
233    13. In the pathological case when an offset vector of size 2 is used, pcretest
234        now prints out the matched string after a yield of 0 or 1.
235    
236    14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
237        Only supported by the JIT compiler at the moment.
238    
239    15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
240    
241    16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
242        offset of the starting point of the matching process, provided the offsets
243        vector is large enough.
244    
245    17. The \A escape now records a lookbehind value of 1, though its execution
246        does not actually inspect the previous character. This is to ensure that,
247        in partial multi-segment matching, at least one character from the old
248        segment is retained when a new segment is processed. Otherwise, if there
249        are no lookbehinds in the pattern, \A might match incorrectly at the start
250        of a new segment.
251    
252    18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
253    
254    19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
255        gives some modest performance improvement in 8-bit mode.
256    
257    20. Added the PCRE-specific property \p{Xuc} for matching characters that can
258        be expressed in certain programming languages using Universal Character
259        Names.
260    
261    21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
262        which points out that "non characters" are not "characters that may not
263        appear in Unicode strings" but rather "characters that are reserved for
264        internal use and have only local meaning".
265    
266    22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
267        there was a conditional group that depended on an assertion, if the
268        assertion was false, the callout that immediately followed the alternation
269        in the condition was skipped when pcre_exec() was used for matching.
270    
271    23. Allow an explicit callout to be inserted before an assertion that is the
272        condition for a conditional group, for compatibility with automatic
273        callouts, which always insert a callout at this point.
274    
275    24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
276        confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
277    
278    25. (*PRUNE) is now supported by the JIT compiler.
279    
280    26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
281    
282    27. Fix the case where there are two or more SKIPs with arguments that may be
283        ignored.
284    
285    28. (*SKIP) is now supported by the JIT compiler.
286    
287    29. (*THEN) is now supported by the JIT compiler.
288    
289    30. Update RunTest with additional test selector options.
290    
291    31. The way PCRE handles backtracking verbs has been changed in two ways.
292    
293        (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
294        SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
295        backtracking. In some cases this makes it more Perl-compatible, but Perl's
296        rather obscure rules do not always do the same thing.
297    
298        (2) Previously, backtracking verbs were confined within assertions. This is
299        no longer the case for positive assertions, except for (*ACCEPT). Again,
300        this sometimes improves Perl compatibility, and sometimes does not.
301    
302    32. A number of tests that were in test 2 because Perl did things differently
303        have been moved to test 1, because either Perl or PCRE has changed, and
304        these tests are now compatible.
305    
306    32. Backtracking control verbs are now handled in the same way in JIT and
307        interpreter.
308    
309    33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
310        contained a forward subroutine reference caused a compile error.
311    
312    34. Auto-detect and optimize limited repetitions in JIT.
313    
314    35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
315        blocking (*UTF) etc.
316    
317    36. In the interpreter, maximizing pattern repetitions for characters and
318        character types now use tail recursion, which reduces stack usage.
319    
320    37. The value of the max lookbehind was not correctly preserved if a compiled
321        and saved regex was reloaded on a host of different endianness.
322    
323    38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
324        of the compiled pattern block, expand the flags field from 16 to 32 bits
325        because it was almost full.
326    
327    39. Try madvise first before posix_madvise.
328    
329    40. Change 7 for PCRE 7.9 made it impossible for pcregrep to find empty lines
330        with a pattern such as ^$. It has taken 4 years for anybody to notice! The
331        original change locked out all matches of empty strings. This has been
332        changed so that one match of an empty string per line is recognized.
333        Subsequent searches on the same line (for colouring or for --only-matching,
334        for example) do not recognize empty strings.
335    
336    41. Applied a user patch to fix a number of spelling mistakes in comments.
337    
338    42. Data lines longer than 65536 caused pcretest to crash.
339    
340    43. Clarified the data type for length and startoffset arguments for pcre_exec
341        and pcre_dfa_exec in the function-specific man pages, where they were
342        explicitly stated to be in bytes, never having been updated. I also added
343        some clarification to the pcreapi man page.
344    
345    44. A call to pcre_dfa_exec() with an output vector size less than 2 caused
346        a segmentation fault.
347    
348    
349    Version 8.32 30-November-2012
350    -----------------------------
351    
352    1.  Improved JIT compiler optimizations for first character search and single
353        character iterators.
354    
355    2.  Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
356        Patch by Daniel Richard G.
357    
358    3.  Single character iterator optimizations in the JIT compiler.
359    
360    4.  Improved JIT compiler optimizations for character ranges.
361    
362    5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
363        Reported by Giuseppe D'Angelo.
364    
365    6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
366        of a line, was being set incorrectly in cases where .* appeared inside
367        atomic brackets at the start of a pattern, or where there was a subsequent
368        *PRUNE or *SKIP.
369    
370    7.  Improved instruction cache flush for POWER/PowerPC.
371        Patch by Daniel Richard G.
372    
373    8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
374        grep:
375    
376        (a) There is now no limit to the number of patterns to be matched.
377    
378        (b) An error is given if a pattern is too long.
379    
380        (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
381            are now supported.
382    
383        (d) --exclude-from and --include-from (multiple use) have been added.
384    
385        (e) Exclusions and inclusions now apply to all files and directories, not
386            just to those obtained from scanning a directory recursively.
387    
388        (f) Multiple uses of -f and --file-list are now supported.
389    
390        (g) In a Windows environment, the default for -d has been changed from
391            "read" (the GNU grep default) to "skip", because otherwise the presence
392            of a directory in the file list provokes an error.
393    
394        (h) The documentation has been revised and clarified in places.
395    
396    9.  Improve the matching speed of capturing brackets.
397    
398    10. Changed the meaning of \X so that it now matches a Unicode extended
399        grapheme cluster.
400    
401    11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
402        out POSIX threads when JIT support is configured.
403    
404    12. Added support for PCRE_STUDY_EXTRA_NEEDED.
405    
406    13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
407        structure could go wrong in environments where size_t is not the same size
408        as int.
409    
410    14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
411        set.
412    
413    15. The EBCDIC support had decayed; later updates to the code had included
414        explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
415        general tidy up of EBCDIC-related issues, and the documentation was also
416        not quite right. There is now a test that can be run on ASCII systems to
417        check some of the EBCDIC-related things (but is it not a full test).
418    
419    16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
420        in a small tidy to the code.
421    
422    17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
423    
424    18. If the --only-matching (-o) option in pcregrep is specified multiple
425        times, each one causes appropriate output. For example, -o1 -o2 outputs the
426        substrings matched by the 1st and 2nd capturing parentheses. A separating
427        string can be specified by --om-separator (default empty).
428    
429    19. Improving the first n character searches.
430    
431    20. Turn case lists for horizontal and vertical white space into macros so that
432        they are defined only once.
433    
434    21. This set of changes together give more compatible Unicode case-folding
435        behaviour for characters that have more than one other case when UCP
436        support is available.
437    
438        (a) The Unicode property table now has offsets into a new table of sets of
439            three or more characters that are case-equivalent. The MultiStage2.py
440            script that generates these tables (the pcre_ucd.c file) now scans
441            CaseFolding.txt instead of UnicodeData.txt for character case
442            information.
443    
444        (b) The code for adding characters or ranges of characters to a character
445            class has been abstracted into a generalized function that also handles
446            case-independence. In UTF-mode with UCP support, this uses the new data
447            to handle characters with more than one other case.
448    
449        (c) A bug that is fixed as a result of (b) is that codepoints less than 256
450            whose other case is greater than 256 are now correctly matched
451            caselessly. Previously, the high codepoint matched the low one, but not
452            vice versa.
453    
454        (d) The processing of \h, \H, \v, and \ in character classes now makes use
455            of the new class addition function, using character lists defined as
456            macros alongside the case definitions of 20 above.
457    
458        (e) Caseless back references now work with characters that have more than
459            one other case.
460    
461        (f) General caseless matching of characters with more than one other case
462            is supported.
463    
464    22. Unicode character properties were updated from Unicode 6.2.0
465    
466    23. Improved CMake support under Windows. Patch by Daniel Richard G.
467    
468    24. Add support for 32-bit character strings, and UTF-32
469    
470    25. Major JIT compiler update (code refactoring and bugfixing).
471        Experimental Sparc 32 support is added.
472    
473    26. Applied a modified version of Daniel Richard G's patch to create
474        pcre.h.generic and config.h.generic by "make" instead of in the
475        PrepareRelease script.
476    
477    27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
478        pcre_compile.c when checking for a zero character.
479    
480    28. Introducing a native interface for JIT. Through this interface, the compiled
481        machine code can be directly executed. The purpose of this interface is to
482        provide fast pattern matching, so several sanity checks are not performed.
483        However, feature tests are still performed. The new interface provides
484        1.4x speedup compared to the old one.
485    
486    29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
487        the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
488        was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
489    
490    30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
491        greater than 0x7fffffff (which cannot be represented in UTF-8, even under
492        the "old" RFC 2279). Instead, it ended up passing a negative length to
493        pcre_exec().
494    
495    31. Add support for GCC's visibility feature to hide internal functions.
496    
497    32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
498        "unknown -C option" after outputting 0 or 1.
499    
500    33. There is now support for generating a code coverage report for the test
501        suite in environments where gcc is the compiler and lcov is installed. This
502        is mainly for the benefit of the developers.
503    
504    34. If PCRE is built with --enable-valgrind, certain memory regions are marked
505        unaddressable using valgrind annotations, allowing valgrind to detect
506        invalid memory accesses. This is mainly for the benefit of the developers.
507    
508    25. (*UTF) can now be used to start a pattern in any of the three libraries.
509    
510    26. Give configure error if --enable-cpp but no C++ compiler found.
511    
512    
513    Version 8.31 06-July-2012
514    -------------------------
515    
516    1.  Fixing a wrong JIT test case and some compiler warnings.
517    
518    2.  Removed a bashism from the RunTest script.
519    
520    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
521        to unsigned type, result still unsigned" that was given by an MS compiler
522        on encountering the code "-sizeof(xxx)".
523    
524    4.  Partial matching support is added to the JIT compiler.
525    
526    5.  Fixed several bugs concerned with partial matching of items that consist
527        of more than one character:
528    
529        (a) /^(..)\1/ did not partially match "aba" because checking references was
530            done on an "all or nothing" basis. This also applied to repeated
531            references.
532    
533        (b) \R did not give a hard partial match if \r was found at the end of the
534            subject.
535    
536        (c) \X did not give a hard partial match after matching one or more
537            characters at the end of the subject.
538    
539        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
540            a partial match for the string "\r".
541    
542        (e) When newline was set to CRLF, the metacharacter "." did not recognize
543            a partial match for a CR character at the end of the subject string.
544    
545    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
546        running pcretest, the text "(JIT)" added to the output whenever JIT is
547        actually used to run the match.
548    
549    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
550        or /S+[+] with a digit between 1 and 7.
551    
552    8.  OP_NOT now supports any UTF character not just single-byte ones.
553    
554    9.  (*MARK) control verb is now supported by the JIT compiler.
555    
556    10. The command "./RunTest list" lists the available tests without actually
557        running any of them. (Because I keep forgetting what they all are.)
558    
559    11. Add PCRE_INFO_MAXLOOKBEHIND.
560    
561    12. Applied a (slightly modified) user-supplied patch that improves performance
562        when the heap is used for recursion (compiled with --disable-stack-for-
563        recursion). Instead of malloc and free for each heap frame each time a
564        logical recursion happens, frames are retained on a chain and re-used where
565        possible. This sometimes gives as much as 30% improvement.
566    
567    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
568        call.
569    
570    14. As documented, (*COMMIT) is now confined to within a positive assertion.
571    
572    15. It is now possible to link pcretest with libedit as an alternative to
573        libreadline.
574    
575    16. (*COMMIT) control verb is now supported by the JIT compiler.
576    
577    17. The Unicode data tables have been updated to Unicode 6.1.0.
578    
579    18. Added --file-list option to pcregrep.
580    
581    19. Added binary file support to pcregrep, including the -a, --binary-files,
582        -I, and --text options.
583    
584    20. The madvise function is renamed for posix_madvise for QNX compatibility
585        reasons. Fixed by Giuseppe D'Angelo.
586    
587    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
588    
589    22. Changed the option for creating symbolic links for 16-bit man pages from
590        -s to -sf so that re-installing does not cause issues.
591    
592    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
593    
594    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
595        matches in certain environments (the workspace was not being correctly
596        retained). Also added to pcre_dfa_exec() a simple plausibility check on
597        some of the workspace data at the beginning of a restart.
598    
599    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
600        was not doing so when it should - probably a typo introduced by SVN 528
601        (change 8.10/14).
602    
603    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
604        \w+ when the character tables indicated that \x{c4} was a word character.
605        There were several related cases, all because the tests for doing a table
606        lookup were testing for characters less than 127 instead of 255.
607    
608    27. If a pattern contains capturing parentheses that are not used in a match,
609        their slots in the ovector are set to -1. For those that are higher than
610        any matched groups, this happens at the end of processing. In the case when
611        there were back references that the ovector was too small to contain
612        (causing temporary malloc'd memory to be used during matching), and the
613        highest capturing number was not used, memory off the end of the ovector
614        was incorrectly being set to -1. (It was using the size of the temporary
615        memory instead of the true size.)
616    
617    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
618        ovector size, it uses memory at the end of the block that it has got.
619    
620    29. Check for an overlong MARK name and give an error at compile time. The
621        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
622    
623    30. JIT compiler update.
624    
625    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
626        Rill for the patch.
627    
628    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
629    
630    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
631    
632    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
633        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
634        was enabled.
635    
636    35. Improve JIT code generation for greedy plus quantifier.
637    
638    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
639        1 to "aa" instead of to an empty string. The bug affected repeated groups
640        that could potentially match an empty string.
641    
642    37. Optimizing single character iterators in JIT.
643    
644    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
645        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
646        codepoints that are too big for the mode are faulted, and in a UTF mode,
647        disallowed codepoints are also faulted.
648    
649    39. If PCRE was compiled with UTF support, in three places in the DFA
650        matcher there was code that should only have been obeyed in UTF mode, but
651        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
652        processing when bytes with values greater than 127 were present. In 16-bit
653        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
654        both cases the values are those that cannot be the first data item in a UTF
655        character. The three items that might have provoked this were recursions,
656        possessively repeated groups, and atomic groups.
657    
658    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
659        and pcregrep, because some OS require shared objects to be explicitly
660        passed to ld, causing the link step to fail if they are not.
661    
662    41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
663        mode, patterns that started with \h* or \R* might be incorrectly matched.
664    
665    
666    Version 8.30 04-February-2012
667    -----------------------------
668    
669    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
670        name is defined in ctype.h.
671    
672    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
673        only in quite long subpatterns.
674    
675    3.  Removed the function pcre_info(), which has been obsolete and deprecated
676        since it was replaced by pcre_fullinfo() in February 2000.
677    
678    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
679        match a (*MARK), and the match failed at the start of the subject, a
680        reference to memory before the start of the subject could occur. This bug
681        was introduced by fix 17 of release 8.21.
682    
683    5.  A reference to an unset group with zero minimum repetition was giving
684        totally wrong answers (in non-JavaScript-compatibility mode). For example,
685        /(another)?(\1?)test/ matched against "hello world test". This bug was
686        introduced in release 8.13.
687    
688    6.  Add support for 16-bit character strings (a large amount of work involving
689        many changes and refactorings).
690    
691    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
692        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
693        from a file.
694    
695    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
696        rounding is not applied in this particular case).
697    
698    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
699        if they appear, or are escaped, in patterns.
700    
701    10. Get rid of a number of -Wunused-but-set-variable warnings.
702    
703    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
704        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
705        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
706        also returns the mark "x". This bug applied to capturing parentheses,
707        non-capturing parentheses, and atomic parentheses. It also applied to some
708        assertions.
709    
710    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
711        information out of configure.ac instead of relying on pcre.h.generic, which
712        is not stored in the repository.
713    
714    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
715        -lreadline.
716    
717    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
718    
719    15. Applied Graycode's patch to put the top-level frame on the stack rather
720        than the heap when not using the stack for recursion. This gives a
721        performance improvement in many cases when recursion is not deep.
722    
723    16. Experimental code added to "pcretest -C" to output the stack frame size.
724    
725    
726    Version 8.21 12-Dec-2011
727    ------------------------
728    
729    1.  Updating the JIT compiler.
730    
731    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
732        are added as well.
733    
734    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
735        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
736        calling _pcre_jit_exec. Some extra comments are added.
737    
738    4.  (*MARK) settings inside atomic groups that do not contain any capturing
739        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
740        was introduced by change 18 for 8.20.
741    
742    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
743        ECMA-262 standard.
744    
745    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
746        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
747        This bug was probably introduced by change 9 of 8.13.
748    
749    7.  While fixing 6 above, I noticed that a number of other items were being
750        incorrectly rejected as "not fixed length". This arose partly because newer
751        opcodes had not been added to the fixed-length checking code. I have (a)
752        corrected the bug and added tests for these items, and (b) arranged for an
753        error to occur if an unknown opcode is encountered while checking for fixed
754        length instead of just assuming "not fixed length". The items that were
755        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
756        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
757        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
758    
759    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
760        being incorrectly compiled and would have given unpredicatble results.
761    
762    9.  A possessively repeated subpattern with minimum repeat count greater than
763        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
764        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
765        the first (A) could occur when it should not.
766    
767    10. Add a cast and remove a redundant test from the code.
768    
769    11. JIT should use pcre_malloc/pcre_free for allocation.
770    
771    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
772        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
773        is anything other than /usr, -L is still shown).
774    
775    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
776    
777    14. Perl does not support \N without a following name in a [] class; PCRE now
778        also gives an error.
779    
780    15. If a forward reference was repeated with an upper limit of around 2000,
781        it caused the error "internal error: overran compiling workspace". The
782        maximum number of forward references (including repeats) was limited by the
783        internal workspace, and dependent on the LINK_SIZE. The code has been
784        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
785        the default depends on LINK_SIZE. There is a new upper limit (for safety)
786        of around 200,000 forward references. While doing this, I also speeded up
787        the filling in of repeated forward references.
788    
789    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
790        incorrectly expecting the subject to contain another "a" after the start.
791    
792    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
793        in the match, the SKIP should be ignored. This was not happening; instead
794        the SKIP was being treated as NOMATCH. For patterns such as
795        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
796        tested.
797    
798    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
799        now much more compatible with Perl, in particular in cases where the result
800        is a non-match for a non-anchored pattern. For example, if
801        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
802        "m", where previously it did not return a name. A side effect of this
803        change is that for partial matches, the last encountered mark name is
804        returned, as for non matches. A number of tests that were previously not
805        Perl-compatible have been moved into the Perl-compatible test files. The
806        refactoring has had the pleasing side effect of removing one argument from
807        the match() function, thus reducing its stack requirements.
808    
809    19. If the /S+ option was used in pcretest to study a pattern using JIT,
810        subsequent uses of /S (without +) incorrectly behaved like /S+.
811    
812    21. Retrieve executable code size support for the JIT compiler and fixing
813        some warnings.
814    
815    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
816        not work when the shorter character appeared right at the end of the
817        subject string.
818    
819    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
820        systems.
821    
822    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
823        output it when the /M option is used in pcretest.
824    
825    25. The CheckMan script was not being included in the distribution. Also, added
826        an explicit "perl" to run Perl scripts from the PrepareRelease script
827        because this is reportedly needed in Windows.
828    
829    26. If study data was being save in a file and studying had not found a set of
830        "starts with" bytes for the pattern, the data written to the file (though
831        never used) was taken from uninitialized memory and so caused valgrind to
832        complain.
833    
834    27. Updated RunTest.bat as provided by Sheri Pierce.
835    
836    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
837    
838    29. Computation of memory usage for the table of capturing group names was
839        giving an unnecessarily large value.
840    
841    
842    Version 8.20 21-Oct-2011
843    ------------------------
844    
845    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
846        a POSIX class. After further experiments with Perl, which convinced me that
847        Perl has bugs and confusions, a closing square bracket is no longer allowed
848        in a POSIX name. This bug also affected patterns with classes that started
849        with full stops.
850    
851    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
852        captured substring, but while checking the failing first alternative,
853        substring 1 is temporarily captured. If the output vector supplied to
854        pcre_exec() was not big enough for this capture, the yield of the function
855        was still zero ("insufficient space for captured substrings"). This cannot
856        be totally fixed without adding another stack variable, which seems a lot
857        of expense for a edge case. However, I have improved the situation in cases
858        such as /(a)(b)x|abc/ matched against "abc", where the return code
859        indicates that fewer than the maximum number of slots in the ovector have
860        been set.
861    
862    3.  Related to (2) above: when there are more back references in a pattern than
863        slots in the output vector, pcre_exec() uses temporary memory during
864        matching, and copies in the captures as far as possible afterwards. It was
865        using the entire output vector, but this conflicts with the specification
866        that only 2/3 is used for passing back captured substrings. Now it uses
867        only the first 2/3, for compatibility. This is, of course, another edge
868        case.
869    
870    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
871        main code base, and can be used by building with --enable-jit. When this is
872        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
873        runtime --no-jit option is given.
874    
875    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
876        ovector, the return from the function was zero, implying that there were
877        other matches that did not fit. The correct "exactly full" value is now
878        returned.
879    
880    6.  If a subpattern that was called recursively or as a subroutine contained
881        (*PRUNE) or any other control that caused it to give a non-standard return,
882        invalid errors such as "Error -26 (nested recursion at the same subject
883        position)" or even infinite loops could occur.
884    
885    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
886        computing the minimum length on reaching *ACCEPT, and so ended up with the
887        wrong value of 1 rather than 0. Further investigation indicates that
888        computing a minimum subject length in the presence of *ACCEPT is difficult
889        (think back references, subroutine calls), and so I have changed the code
890        so that no minimum is registered for a pattern that contains *ACCEPT.
891    
892    8.  If (*THEN) was present in the first (true) branch of a conditional group,
893        it was not handled as intended. [But see 16 below.]
894    
895    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
896        Sheri Pierce.
897    
898    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
899        the first byte in a match must be "a".
900    
901    11. Change 17 for 8.13 increased the recursion depth for patterns like
902        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
903        pattern contains any instances of (*THEN). If it does not, the old
904        optimizations are restored. It would be nice to do this on a per-group
905        basis, but at the moment that is not feasible.
906    
907    12. In some environments, the output of pcretest -C is CRLF terminated. This
908        broke RunTest's code that checks for the link size. A single white space
909        character after the value is now allowed for.
910    
911    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
912        For "fr", it uses the Windows-specific input and output files.
913    
914    14. If (*THEN) appeared in a group that was called recursively or as a
915        subroutine, it did not work as intended. [But see next item.]
916    
917    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
918        pattern fragments (but not containing any | characters). If A and B are
919        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
920        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
921        D. In other words, Perl considers parentheses that do not contain any |
922        characters to be part of a surrounding alternative, whereas PCRE was
923        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
924        differently. PCRE now behaves in the same way as Perl, except in the case
925        of subroutine/recursion calls such as (?1) which have in any case always
926        been different (but PCRE had them first :-).
927    
928    16. Related to 15 above: Perl does not treat the | in a conditional group as
929        creating alternatives. Such a group is treated in the same way as an
930        ordinary group without any | characters when processing (*THEN). PCRE has
931        been changed to match Perl's behaviour.
932    
933    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
934        RunGrepTest script failed.
935    
936    18. Change 22 for version 13 caused atomic groups to use more stack. This is
937        inevitable for groups that contain captures, but it can lead to a lot of
938        stack use in large patterns. The old behaviour has been restored for atomic
939        groups that do not contain any capturing parentheses.
940    
941    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
942        suppress the check for a minimum subject length at run time. (If it was
943        given to pcre_exec() or pcre_dfa_exec() it did work.)
944    
945    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
946        fail to work when decoding hex characters in data strings in EBCDIC
947        environments.
948    
949    21. It appears that in at least one Mac OS environment, the isxdigit() function
950        is implemented as a macro that evaluates to its argument more than once,
951        contravening the C 90 Standard (I haven't checked a later standard). There
952        was an instance in pcretest which caused it to go wrong when processing
953        \x{...} escapes in subject strings. The has been rewritten to avoid using
954        things like p++ in the argument of isxdigit().
955    
956    
957    Version 8.13 16-Aug-2011
958    ------------------------
959    
960    1.  The Unicode data tables have been updated to Unicode 6.0.0.
961    
962    2.  Two minor typos in pcre_internal.h have been fixed.
963    
964    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
965        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
966        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
967    
968    4.  There were a number of related bugs in the code for matching backrefences
969        caselessly in UTF-8 mode when codes for the characters concerned were
970        different numbers of bytes. For example, U+023A and U+2C65 are an upper
971        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
972        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
973        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
974        2-byte code at the end of the subject (it thought there wasn't enough data
975        left).
976    
977    5.  Comprehensive information about what went wrong is now returned by
978        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
979        as the output vector has at least 2 elements. The offset of the start of
980        the failing character and a reason code are placed in the vector.
981    
982    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
983        now returned is for the first byte of the failing character, instead of the
984        last byte inspected. This is an incompatible change, but I hope it is small
985        enough not to be a problem. It makes the returned offset consistent with
986        pcre_exec() and pcre_dfa_exec().
987    
988    7.  pcretest now gives a text phrase as well as the error number when
989        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
990        failure, the offset and reason code are output.
991    
992    8.  When \R was used with a maximizing quantifier it failed to skip backwards
993        over a \r\n pair if the subsequent match failed. Instead, it just skipped
994        back over a single character (\n). This seems wrong (because it treated the
995        two characters as a single entity when going forwards), conflicts with the
996        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
997        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
998        has been changed.
999    
1000    9.  Some internal refactoring has changed the processing so that the handling
1001        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
1002        time (the PCRE_DOTALL option was changed this way some time ago: version
1003        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
1004        which was always a bit of a fudge. It also means that there is one less
1005        argument for the match() function, which reduces its stack requirements
1006        slightly. This change also fixes an incompatibility with Perl: the pattern
1007        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
1008    
1009    10. More internal refactoring has drastically reduced the number of recursive
1010        calls to match() for possessively repeated groups such as (abc)++ when
1011        using pcre_exec().
1012    
1013    11. While implementing 10, a number of bugs in the handling of groups were
1014        discovered and fixed:
1015    
1016        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
1017        (a|)*(?1) gave a compile-time internal error.
1018        ((a|)+)+  did not notice that the outer group could match an empty string.
1019        (^a|^)+   was not marked as anchored.
1020        (.*a|.*)+ was not marked as matching at start or after a newline.
1021    
1022    12. Yet more internal refactoring has removed another argument from the match()
1023        function. Special calls to this function are now indicated by setting a
1024        value in a variable in the "match data" data block.
1025    
1026    13. Be more explicit in pcre_study() instead of relying on "default" for
1027        opcodes that mean there is no starting character; this means that when new
1028        ones are added and accidentally left out of pcre_study(), testing should
1029        pick them up.
1030    
1031    14. The -s option of pcretest has been documented for ages as being an old
1032        synonym of -m (show memory usage). I have changed it to mean "force study
1033        for every regex", that is, assume /S for every regex. This is similar to -i
1034        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
1035        using it. It makes it easier to run collections of tests with and without
1036        study enabled, and thereby test pcre_study() more easily. All the standard
1037        tests are now run with and without -s (but some patterns can be marked as
1038        "never study" - see 20 below).
1039    
1040    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
1041        restoration of the capturing data to the outer values was not happening
1042        correctly.
1043    
1044    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
1045        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
1046        pattern had matched an empty string, and so incorrectly returned a no
1047        match.
1048    
1049    17. There was optimizing code for the last branch of non-capturing parentheses,
1050        and also for the obeyed branch of a conditional subexpression, which used
1051        tail recursion to cut down on stack usage. Unfortunately, now that there is
1052        the possibility of (*THEN) occurring in these branches, tail recursion is
1053        no longer possible because the return has to be checked for (*THEN). These
1054        two optimizations have therefore been removed. [But see 8.20/11 above.]
1055    
1056    18. If a pattern containing \R was studied, it was assumed that \R always
1057        matched two bytes, thus causing the minimum subject length to be
1058        incorrectly computed because \R can also match just one byte.
1059    
1060    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
1061        was incorrectly computed.
1062    
1063    20. If /S is present twice on a test pattern in pcretest input, it now
1064        *disables* studying, thereby overriding the use of -s on the command line
1065        (see 14 above). This is necessary for one or two tests to keep the output
1066        identical in both cases.
1067    
1068    21. When (*ACCEPT) was used in an assertion that matched an empty string and
1069        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
1070    
1071    22. When an atomic group that contained a capturing parenthesis was
1072        successfully matched, but the branch in which it appeared failed, the
1073        capturing was not being forgotten if a higher numbered group was later
1074        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
1075        group 1 to "a", when in fact it should be unset. This applied to multi-
1076        branched capturing and non-capturing groups, repeated or not, and also to
1077        positive assertions (capturing in negative assertions does not happen
1078        in PCRE) and also to nested atomic groups.
1079    
1080    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
1081        subject after a captured substring, to make it easier to tell which of a
1082        number of identical substrings has been captured.
1083    
1084    24. The way atomic groups are processed by pcre_exec() has been changed so that
1085        if they are repeated, backtracking one repetition now resets captured
1086        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
1087        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
1088        "aaa". Previously, it would have been "a". As part of this code
1089        refactoring, the way recursive calls are handled has also been changed.
1090    
1091    25. If an assertion condition captured any substrings, they were not passed
1092        back unless some other capturing happened later. For example, if
1093        (?(?=(a))a) was matched against "a", no capturing was returned.
1094    
1095    26. When studying a pattern that contained subroutine calls or assertions,
1096        the code for finding the minimum length of a possible match was handling
1097        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
1098        group 1 called group 2 while simultaneously a separate group 2 called group
1099        1). A stack overflow occurred in this case. I have fixed this by limiting
1100        the recursion depth to 10.
1101    
1102    27. Updated RunTest.bat in the distribution to the version supplied by Tom
1103        Fortmann. This supports explicit test numbers on the command line, and has
1104        argument validation and error reporting.
1105    
1106    28. An instance of \X with an unlimited repeat could fail if at any point the
1107        first character it looked at was a mark character.
1108    
1109    29. Some minor code refactoring concerning Unicode properties and scripts
1110        should reduce the stack requirement of match() slightly.
1111    
1112    30. Added the '=' option to pcretest to check the setting of unused capturing
1113        slots at the end of the pattern, which are documented as being -1, but are
1114        not included in the return count.
1115    
1116    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
1117        compiled something random. Now it gives a compile-time error (as does
1118        Perl).
1119    
1120    32. A *MARK encountered during the processing of a positive assertion is now
1121        recorded and passed back (compatible with Perl).
1122    
1123    33. If --only-matching or --colour was set on a pcregrep call whose pattern
1124        had alternative anchored branches, the search for a second match in a line
1125        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
1126        matched the line "0102" twice. The same bug affected patterns that started
1127        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
1128        twice.
1129    
1130    34. Previously, PCRE did not allow quantification of assertions. However, Perl
1131        does, and because of capturing effects, quantifying parenthesized
1132        assertions may at times be useful. Quantifiers are now allowed for
1133        parenthesized assertions.
1134    
1135    35. A minor code tidy in pcre_compile() when checking options for \R usage.
1136    
1137    36. \g was being checked for fancy things in a character class, when it should
1138        just be a literal "g".
1139    
1140    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
1141        appearance of a nested POSIX class supersedes an apparent external class.
1142        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
1143        unescaped square brackets may also appear as part of class names. For
1144        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
1145        more like Perl. (But see 8.20/1 above.)
1146    
1147    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
1148        was because it thought it was \N{name}, which is not supported).
1149    
1150    39. Add minix to OS list not supporting the -S option in pcretest.
1151    
1152    40. PCRE tries to detect cases of infinite recursion at compile time, but it
1153        cannot analyze patterns in sufficient detail to catch mutual recursions
1154        such as ((?1))((?2)). There is now a runtime test that gives an error if a
1155        subgroup is called recursively as a subpattern for a second time at the
1156        same position in the subject string. In previous releases this might have
1157        been caught by the recursion limit, or it might have run out of stack.
1158    
1159    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
1160        happen only once. PCRE was, however incorrectly giving a compile time error
1161        "recursive call could loop indefinitely" because it cannot analyze the
1162        pattern in sufficient detail. The compile time test no longer happens when
1163        PCRE is compiling a conditional subpattern, but actual runaway loops are
1164        now caught at runtime (see 40 above).
1165    
1166    42. It seems that Perl allows any characters other than a closing parenthesis
1167        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
1168        has been changed to be the same.
1169    
1170    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
1171        as not to get warnings when autogen.sh is called. Also changed
1172        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
1173    
1174    44. To help people who use pcregrep to scan files containing exceedingly long
1175        lines, the following changes have been made:
1176    
1177        (a) The default value of the buffer size parameter has been increased from
1178            8K to 20K. (The actual buffer used is three times this size.)
1179    
1180        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
1181            PCRE is built.
1182    
1183        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
1184            to be set at run time.
1185    
1186        (d) Numerical values in pcregrep options can be followed by K or M, for
1187            example --buffer-size=50K.
1188    
1189        (e) If a line being scanned overflows pcregrep's buffer, an error is now
1190            given and the return code is set to 2.
1191    
1192    45. Add a pointer to the latest mark to the callout data block.
1193    
1194    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
1195        partial match of an empty string instead of no match. This was specific to
1196        the use of ".".
1197    
1198    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
1199        complete match instead of a partial match. This bug was dependent on both
1200        the PCRE_UTF8 and PCRE_DOTALL options being set.
1201    
1202    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
1203        starting byte set, because \b was not being ignored.
1204    
1205    
1206    Version 8.12 15-Jan-2011
1207    ------------------------
1208    
1209    1.  Fixed some typos in the markup of the man pages, and wrote a script that
1210        checks for such things as part of the documentation building process.
1211    
1212    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
1213        --match-limit and --recursion-limit options (added for 8.11). In
1214        particular, this made one of the standard tests fail. (The integer value
1215        went into the wrong half of a long int.)
1216    
1217    3.  If the --colour option was given to pcregrep with -v (invert match), it
1218        did strange things, either producing crazy output, or crashing. It should,
1219        of course, ignore a request for colour when reporting lines that do not
1220        match.
1221    
1222    4.  Another pcregrep bug caused similar problems if --colour was specified with
1223        -M (multiline) and the pattern match finished with a line ending.
1224    
1225    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
1226        matched in multiline mode, the following line was shown as part of the
1227        match. This seems wrong, so I have changed it.
1228    
1229    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
1230        the check for further matches in the same line (so they could be coloured)
1231        to overrun the end of the current line. If another match was found, it was
1232        incorrectly shown (and then shown again when found in the next line).
1233    
1234    7.  If pcregrep was compiled under Windows, there was a reference to the
1235        function pcregrep_exit() before it was defined. I am assuming this was
1236        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
1237        reported by a user. I've moved the definition above the reference.
1238    
1239    
1240    Version 8.11 10-Dec-2010
1241    ------------------------
1242    
1243    1.  (*THEN) was not working properly if there were untried alternatives prior
1244        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
1245        backtracked to try for "b" instead of moving to the next alternative branch
1246        at the same level (in this case, to look for "c"). The Perl documentation
1247        is clear that when (*THEN) is backtracked onto, it goes to the "next
1248        alternative in the innermost enclosing group".
1249    
1250    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
1251        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
1252        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
1253        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
1254        (*THEN).
1255    
1256    3.  If \s appeared in a character class, it removed the VT character from
1257        the class, even if it had been included by some previous item, for example
1258        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
1259        of \s, but is part of the POSIX "space" class.)
1260    
1261    4.  A partial match never returns an empty string (because you can always
1262        match an empty string at the end of the subject); however the checking for
1263        an empty string was starting at the "start of match" point. This has been
1264        changed to the "earliest inspected character" point, because the returned
1265        data for a partial match starts at this character. This means that, for
1266        example, /(?<=abc)def/ gives a partial match for the subject "abc"
1267        (previously it gave "no match").
1268    
1269    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
1270        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
1271        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
1272        has an implication that the given string is incomplete (because a partial
1273        match is preferred over a full match). For this reason, these items now
1274        give a partial match in this situation. [Aside: previously, the one case
1275        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
1276        match rather than a full match, which was wrong by the old rules, but is
1277        now correct.]
1278    
1279    6.  There was a bug in the handling of #-introduced comments, recognized when
1280        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
1281        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
1282        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
1283        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
1284        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
1285        places in pcre_compile().
1286    
1287    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
1288        comments when looking ahead for named forward references to subpatterns,
1289        the only newline sequence it recognized was NL. It now handles newlines
1290        according to the set newline convention.
1291    
1292    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
1293        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
1294        cater for a lack of strerror(). These oversights have been fixed.
1295    
1296    9.  Added --match-limit and --recursion-limit to pcregrep.
1297    
1298    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
1299    
1300    11. When the -o option was used, pcregrep was setting a return code of 1, even
1301        when matches were found, and --line-buffered was not being honoured.
1302    
1303    12. Added an optional parentheses number to the -o and --only-matching options
1304        of pcregrep.
1305    
1306    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
1307        can match an empty string. The code to do it in pcretest and pcredemo
1308        needed fixing:
1309    
1310        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
1311            only one byte after an empty string match just before CRLF (this case
1312            just got forgotten; "any" and "anycrlf" were OK).
1313    
1314        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
1315            mode when an empty string match preceded an ASCII character followed by
1316            a non-ASCII character. (The code for advancing by one character rather
1317            than one byte was nonsense.)
1318    
1319        (c) The pcredemo.c sample program did not have any code at all to handle
1320            the cases when CRLF is a valid newline sequence.
1321    
1322    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
1323        as a starting offset was within the subject string. There is now a new
1324        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
1325        negative or greater than the length of the string. In order to test this,
1326        pcretest is extended to allow the setting of negative starting offsets.
1327    
1328    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
1329        starting offset points to the beginning of a UTF-8 character was
1330        unnecessarily clumsy. I tidied it up.
1331    
1332    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
1333        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
1334    
1335    17. Nobody had reported that the --include_dir option, which was added in
1336        release 7.7 should have been called --include-dir (hyphen, not underscore)
1337        for compatibility with GNU grep. I have changed it to --include-dir, but
1338        left --include_dir as an undocumented synonym, and the same for
1339        --exclude-dir, though that is not available in GNU grep, at least as of
1340        release 2.5.4.
1341    
1342    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
1343        characters from a string of bytes) have been redefined so as not to use
1344        loops, in order to improve performance in some environments. At the same
1345        time, I abstracted some of the common code into auxiliary macros to save
1346        repetition (this should not affect the compiled code).
1347    
1348    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
1349        compile-time error is now given if \c is not followed by an ASCII
1350        character, that is, a byte less than 128. (In EBCDIC mode, the code is
1351        different, and any byte value is allowed.)
1352    
1353    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
1354        START_OPTIMIZE option, which is now allowed at compile time - but just
1355        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
1356        to pcregrep and other applications that have no direct access to PCRE
1357        options. The new /Y option in pcretest sets this option when calling
1358        pcre_compile().
1359    
1360    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
1361        back references. Groups containing recursive back references were forced to
1362        be atomic by that change, but in the case of named groups, the amount of
1363        memory required was incorrectly computed, leading to "Failed: internal
1364        error: code overflow". This has been fixed.
1365    
1366    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
1367        pcretest.c, to avoid build problems in some Borland environments.
1368    
1369    
1370    Version 8.10 25-Jun-2010
1371    ------------------------
1372    
1373    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
1374        THEN.
1375    
1376    2.  (*ACCEPT) was not working when inside an atomic group.
1377    
1378    3.  Inside a character class, \B is treated as a literal by default, but
1379        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
1380        causes the error). The code is unchanged, but I tidied the documentation.
1381    
1382    4.  Inside a character class, PCRE always treated \R and \X as literals,
1383        whereas Perl faults them if its -w option is set. I have changed PCRE so
1384        that it faults them when PCRE_EXTRA is set.
1385    
1386    5.  Added support for \N, which always matches any character other than
1387        newline. (It is the same as "." when PCRE_DOTALL is not set.)
1388    
1389    6.  When compiling pcregrep with newer versions of gcc which may have
1390        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
1391        declared with attribute warn_unused_result" were given. Just casting the
1392        result to (void) does not stop the warnings; a more elaborate fudge is
1393        needed. I've used a macro to implement this.
1394    
1395    7.  Minor change to pcretest.c to avoid a compiler warning.
1396    
1397    8.  Added four artifical Unicode properties to help with an option to make
1398        \s etc use properties (see next item). The new properties are: Xan
1399        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
1400    
1401    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
1402        use Unicode properties. (*UCP) at the start of a pattern can be used to set
1403        this option. Modified pcretest to add /W to test this facility. Added
1404        REG_UCP to make it available via the POSIX interface.
1405    
1406    10. Added --line-buffered to pcregrep.
1407    
1408    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
1409        studied, and the match started with a letter with a code point greater than
1410        127 whose first byte was different to the first byte of the other case of
1411        the letter, the other case of this starting letter was not recognized
1412        (#976).
1413    
1414    12. If a pattern that was studied started with a repeated Unicode property
1415        test, for example, \p{Nd}+, there was the theoretical possibility of
1416        setting up an incorrect bitmap of starting bytes, but fortunately it could
1417        not have actually happened in practice until change 8 above was made (it
1418        added property types that matched character-matching opcodes).
1419    
1420    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
1421        possible starting bytes for non-anchored patterns.
1422    
1423    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
1424        \R, and also a number of cases that involve Unicode properties, both
1425        explicit and implicit when PCRE_UCP is set.
1426    
1427    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
1428        input, it could crash or give wrong results if characters with values
1429        greater than 0xc0 were present in the subject string. (Detail: it assumed
1430        UTF-8 input when processing these items.)
1431    
1432    16. Added a lot of (int) casts to avoid compiler warnings in systems where
1433        size_t is 64-bit (#991).
1434    
1435    17. Added a check for running out of memory when PCRE is compiled with
1436        --disable-stack-for-recursion (#990).
1437    
1438    18. If the last data line in a file for pcretest does not have a newline on
1439        the end, a newline was missing in the output.
1440    
1441    19. The default pcre_chartables.c file recognizes only ASCII characters (values
1442        less than 128) in its various bitmaps. However, there is a facility for
1443        generating tables according to the current locale when PCRE is compiled. It
1444        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
1445        characters, are recognized by isspace() and therefore were getting set in
1446        these tables, and indeed these tables seem to approximate to ISO 8859. This
1447        caused a problem in UTF-8 mode when pcre_study() was used to create a list
1448        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
1449        which of course cannot start UTF-8 characters. I have changed the code so
1450        that only real ASCII characters (less than 128) and the correct starting
1451        bytes for UTF-8 encodings are set for characters greater than 127 when in
1452        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
1453        altogether.)
1454    
1455    20. Added the /T option to pcretest so as to be able to run tests with non-
1456        standard character tables, thus making it possible to include the tests
1457        used for 19 above in the standard set of tests.
1458    
1459    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
1460        reference to a subpattern the other side of a comment that contains an
1461        opening parenthesis caused either an internal compiling error, or a
1462        reference to the wrong subpattern.
1463    
1464    
1465    Version 8.02 19-Mar-2010
1466    ------------------------
1467    
1468    1.  The Unicode data tables have been updated to Unicode 5.2.0.
1469    
1470    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
1471        configured.
1472    
1473    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
1474        original author of that file, following a query about its status.
1475    
1476    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
1477        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
1478    
1479    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
1480        quantifier applied to a forward-referencing subroutine call, could compile
1481        incorrect code or give the error "internal error: previously-checked
1482        referenced subpattern not found".
1483    
1484    6.  Both MS Visual Studio and Symbian OS have problems with initializing
1485        variables to point to external functions. For these systems, therefore,
1486        pcre_malloc etc. are now initialized to local functions that call the
1487        relevant global functions.
1488    
1489    7.  There were two entries missing in the vectors called coptable and poptable
1490        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
1491        I've fixed the data, and added a kludgy way of testing at compile time that
1492        the lengths are correct (equal to the number of opcodes).
1493    
1494    8.  Following on from 7, I added a similar kludge to check the length of the
1495        eint vector in pcreposix.c.
1496    
1497    9.  Error texts for pcre_compile() are held as one long string to avoid too
1498        much relocation at load time. To find a text, the string is searched,
1499        counting zeros. There was no check for running off the end of the string,
1500        which could happen if a new error number was added without updating the
1501        string.
1502    
1503    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
1504    
1505    11. \K was not working if it appeared in an atomic group or in a group that
1506        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
1507        \K is "not well defined" if used in an assertion. PCRE now accepts it if
1508        the assertion is positive, but not if it is negative.
1509    
1510    12. Change 11 fortuitously reduced the size of the stack frame used in the
1511        "match()" function of pcre_exec.c by one pointer. Forthcoming
1512        implementation of support for (*MARK) will need an extra pointer on the
1513        stack; I have reserved it now, so that the stack frame size does not
1514        decrease.
1515    
1516    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
1517        item in branch that calls a recursion is a subroutine call - as in the
1518        second branch in the above example - was incorrectly given the compile-
1519        time error "recursive call could loop indefinitely" because pcre_compile()
1520        was not correctly checking the subroutine for matching a non-empty string.
1521    
1522    14. The checks for overrunning compiling workspace could trigger after an
1523        overrun had occurred. This is a "should never occur" error, but it can be
1524        triggered by pathological patterns such as hundreds of nested parentheses.
1525        The checks now trigger 100 bytes before the end of the workspace.
1526    
1527    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
1528    
1529    
1530    Version 8.01 19-Jan-2010
1531    ------------------------
1532    
1533    1.  If a pattern contained a conditional subpattern with only one branch (in
1534        particular, this includes all (*DEFINE) patterns), a call to pcre_study()
1535        computed the wrong minimum data length (which is of course zero for such
1536        subpatterns). This could cause incorrect "no match" results.
1537    
1538    2.  For patterns such as (?i)a(?-i)b|c where an option setting at the start of
1539        the pattern is reset in the first branch, pcre_compile() failed with
1540        "internal error: code overflow at offset...". This happened only when
1541        the reset was to the original external option setting. (An optimization
1542        abstracts leading options settings into an external setting, which was the
1543        cause of this.)
1544    
1545    3.  A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
1546        of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
1547        assertion pattern did not match (meaning that the assertion was true), it
1548        was incorrectly treated as false if the SKIP had been reached during the
1549        matching. This also applied to assertions used as conditions.
1550    
1551    4.  If an item that is not supported by pcre_dfa_exec() was encountered in an
1552        assertion subpattern, including such a pattern used as a condition,
1553        unpredictable results occurred, instead of the error return
1554        PCRE_ERROR_DFA_UITEM.
1555    
1556    5.  The C++ GlobalReplace function was not working like Perl for the special
1557        situation when an empty string is matched. It now does the fancy magic
1558        stuff that is necessary.
1559    
1560    6.  In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
1561        removed. (These were left over from very, very early versions of PCRE.)
1562    
1563    7.  Some cosmetic changes to the code to make life easier when compiling it
1564        as part of something else:
1565    
1566        (a) Change DEBUG to PCRE_DEBUG.
1567    
1568        (b) In pcre_compile(), rename the member of the "branch_chain" structure
1569            called "current" as "current_branch", to prevent a collision with the
1570            Linux macro when compiled as a kernel module.
1571    
1572        (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
1573            prevent a collision with the Linux macro when compiled as a kernel
1574            module.
1575    
1576    8.  In pcre_compile() there are some checks for integer overflows that used to
1577        cast potentially large values to (double). This has been changed to that
1578        when building, a check for int64_t is made, and if it is found, it is used
1579        instead, thus avoiding the use of floating point arithmetic. (There is no
1580        other use of FP in PCRE.) If int64_t is not found, the fallback is to
1581        double.
1582    
1583    9.  Added two casts to avoid signed/unsigned warnings from VS Studio Express
1584        2005 (difference between two addresses compared to an unsigned value).
1585    
1586    10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
1587        custom one, because of the following reported problem in Windows:
1588    
1589          - libbz2 uses the Pascal calling convention (WINAPI) for the functions
1590              under Win32.
1591          - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
1592              therefore missing the function definition.
1593          - The compiler thus generates a "C" signature for the test function.
1594          - The linker fails to find the "C" function.
1595          - PCRE fails to configure if asked to do so against libbz2.
1596    
1597    11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
1598        messages were output:
1599    
1600          Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
1601          rerunning libtoolize, to keep the correct libtool macros in-tree.
1602          Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
1603    
1604        I have done both of these things.
1605    
1606    12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
1607        most of the time, it *can* run out if it is given a pattern that contains a
1608        runaway infinite recursion. I updated the discussion in the pcrestack man
1609        page.
1610    
1611    13. Now that we have gone to the x.xx style of version numbers, the minor
1612        version may start with zero. Using 08 or 09 is a bad idea because users
1613        might check the value of PCRE_MINOR in their code, and 08 or 09 may be
1614        interpreted as invalid octal numbers. I've updated the previous comment in
1615        configure.ac, and also added a check that gives an error if 08 or 09 are
1616        used.
1617    
1618    14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
1619        causing partial matching to fail when the end of the subject matched \W
1620        in a UTF-8 pattern where \W was quantified with a minimum of 3.
1621    
1622    15. There were some discrepancies between the declarations in pcre_internal.h
1623        of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
1624        their definitions. The declarations used "const uschar *" and the
1625        definitions used USPTR. Even though USPTR is normally defined as "const
1626        unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
1627        reported that: "This difference in casting confuses some C++ compilers, for
1628        example, SunCC recognizes above declarations as different functions and
1629        generates broken code for hbpcre." I have changed the declarations to use
1630        USPTR.
1631    
1632    16. GNU libtool is named differently on some systems. The autogen.sh script now
1633        tries several variants such as glibtoolize (MacOSX) and libtoolize1x
1634        (FreeBSD).
1635    
1636    17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
1637        (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
1638        comment: "Figure out how to create a longlong from a string: strtoll and
1639        equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
1640        instance, but it only takes 2 args instead of 3!"
1641    
1642    18. A subtle bug concerned with back references has been fixed by a change of
1643        specification, with a corresponding code fix. A pattern such as
1644        ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
1645        refers, was giving matches when it shouldn't. For example, xa=xaaa would
1646        match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
1647        same bug. Such groups have to be quantified to be useful, or contained
1648        inside another quantified group. (If there's no repetition, the reference
1649        can never match.) The problem arises because, having left the group and
1650        moved on to the rest of the pattern, a later failure that backtracks into
1651        the group uses the captured value from the final iteration of the group
1652        rather than the correct earlier one. I have fixed this in PCRE by forcing
1653        any group that contains a reference to itself to be an atomic group; that
1654        is, there cannot be any backtracking into it once it has completed. This is
1655        similar to recursive and subroutine calls.
1656    
1657    
1658    Version 8.00 19-Oct-09
1659    ----------------------
1660    
1661    1.  The table for translating pcre_compile() error codes into POSIX error codes
1662        was out-of-date, and there was no check on the pcre_compile() error code
1663        being within the table. This could lead to an OK return being given in
1664        error.
1665    
1666    2.  Changed the call to open a subject file in pcregrep from fopen(pathname,
1667        "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
1668        in a Windows environment.
1669    
1670    3.  The pcregrep --count option prints the count for each file even when it is
1671        zero, as does GNU grep. However, pcregrep was also printing all files when
1672        --files-with-matches was added. Now, when both options are given, it prints
1673        counts only for those files that have at least one match. (GNU grep just
1674        prints the file name in this circumstance, but including the count seems
1675        more useful - otherwise, why use --count?) Also ensured that the
1676        combination -clh just lists non-zero counts, with no names.
1677    
1678    4.  The long form of the pcregrep -F option was incorrectly implemented as
1679        --fixed_strings instead of --fixed-strings. This is an incompatible change,
1680        but it seems right to fix it, and I didn't think it was worth preserving
1681        the old behaviour.
1682    
1683    5.  The command line items --regex=pattern and --regexp=pattern were not
1684        recognized by pcregrep, which required --regex pattern or --regexp pattern
1685        (with a space rather than an '='). The man page documented the '=' forms,
1686        which are compatible with GNU grep; these now work.
1687    
1688    6.  No libpcreposix.pc file was created for pkg-config; there was just
1689        libpcre.pc and libpcrecpp.pc. The omission has been rectified.
1690    
1691    7.  Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
1692        when UCP support is not needed, by modifying the Python script that
1693        generates it from Unicode data files. This should not matter if the module
1694        is correctly used as a library, but I received one complaint about 50K of
1695        unwanted data. My guess is that the person linked everything into his
1696        program rather than using a library. Anyway, it does no harm.
1697    
1698    8.  A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
1699        was a minimum greater than 1 for a wide character in a possessive
1700        repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
1701        which had an unlimited repeat of a nested, fixed maximum repeat of a wide
1702        character. Chaos in the form of incorrect output or a compiling loop could
1703        result.
1704    
1705    9.  The restrictions on what a pattern can contain when partial matching is
1706        requested for pcre_exec() have been removed. All patterns can now be
1707        partially matched by this function. In addition, if there are at least two
1708        slots in the offset vector, the offset of the earliest inspected character
1709        for the match and the offset of the end of the subject are set in them when
1710        PCRE_ERROR_PARTIAL is returned.
1711    
1712    10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
1713        synonymous with PCRE_PARTIAL, for backwards compatibility, and
1714        PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
1715        and may be more useful for multi-segment matching.
1716    
1717    11. Partial matching with pcre_exec() is now more intuitive. A partial match
1718        used to be given if ever the end of the subject was reached; now it is
1719        given only if matching could not proceed because another character was
1720        needed. This makes a difference in some odd cases such as Z(*FAIL) with the
1721        string "Z", which now yields "no match" instead of "partial match". In the
1722        case of pcre_dfa_exec(), "no match" is given if every matching path for the
1723        final character ended with (*FAIL).
1724    
1725    12. Restarting a match using pcre_dfa_exec() after a partial match did not work
1726        if the pattern had a "must contain" character that was already found in the
1727        earlier partial match, unless partial matching was again requested. For
1728        example, with the pattern /dog.(body)?/, the "must contain" character is
1729        "g". If the first part-match was for the string "dog", restarting with
1730        "sbody" failed. This bug has been fixed.
1731    
1732    13. The string returned by pcre_dfa_exec() after a partial match has been
1733        changed so that it starts at the first inspected character rather than the
1734        first character of the match. This makes a difference only if the pattern
1735        starts with a lookbehind assertion or \b or \B (\K is not supported by
1736        pcre_dfa_exec()). It's an incompatible change, but it makes the two
1737        matching functions compatible, and I think it's the right thing to do.
1738    
1739    14. Added a pcredemo man page, created automatically from the pcredemo.c file,
1740        so that the demonstration program is easily available in environments where
1741        PCRE has not been installed from source.
1742    
1743    15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
1744        libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
1745        library.
1746    
1747    16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
1748        It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
1749        is not the first non-POSIX option to be added. Clearly some people find
1750        these options useful.
1751    
1752    17. If a caller to the POSIX matching function regexec() passes a non-zero
1753        value for nmatch with a NULL value for pmatch, the value of
1754        nmatch is forced to zero.
1755    
1756    18. RunGrepTest did not have a test for the availability of the -u option of
1757        the diff command, as RunTest does. It now checks in the same way as
1758        RunTest, and also checks for the -b option.
1759    
1760    19. If an odd number of negated classes containing just a single character
1761        interposed, within parentheses, between a forward reference to a named
1762        subpattern and the definition of the subpattern, compilation crashed with
1763        an internal error, complaining that it could not find the referenced
1764        subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
1765        [The bug was that it was starting one character too far in when skipping
1766        over the character class, thus treating the ] as data rather than
1767        terminating the class. This meant it could skip too much.]
1768    
1769    20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
1770        /g option in pcretest when the pattern contains \K, which makes it possible
1771        to have an empty string match not at the start, even when the pattern is
1772        anchored. Updated pcretest and pcredemo to use this option.
1773    
1774    21. If the maximum number of capturing subpatterns in a recursion was greater
1775        than the maximum at the outer level, the higher number was returned, but
1776        with unset values at the outer level. The correct (outer level) value is
1777        now given.
1778    
1779    22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
1780        PCRE did not set those parentheses (unlike Perl). I have now found a way to
1781        make it do so. The string so far is captured, making this feature
1782        compatible with Perl.
1783    
1784    23. The tests have been re-organized, adding tests 11 and 12, to make it
1785        possible to check the Perl 5.10 features against Perl 5.10.
1786    
1787    24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
1788        pattern matches a fixed length string. PCRE did not allow this; now it
1789        does. Neither allows recursion.
1790    
1791    25. I finally figured out how to implement a request to provide the minimum
1792        length of subject string that was needed in order to match a given pattern.
1793        (It was back references and recursion that I had previously got hung up
1794        on.) This code has now been added to pcre_study(); it finds a lower bound
1795        to the length of subject needed. It is not necessarily the greatest lower
1796        bound, but using it to avoid searching strings that are too short does give
1797        some useful speed-ups. The value is available to calling programs via
1798        pcre_fullinfo().
1799    
1800    26. While implementing 25, I discovered to my embarrassment that pcretest had
1801        not been passing the result of pcre_study() to pcre_dfa_exec(), so the
1802        study optimizations had never been tested with that matching function.
1803        Oops. What is worse, even when it was passed study data, there was a bug in
1804        pcre_dfa_exec() that meant it never actually used it. Double oops. There
1805        were also very few tests of studied patterns with pcre_dfa_exec().
1806    
1807    27. If (?| is used to create subpatterns with duplicate numbers, they are now
1808        allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
1809        on the other side of the coin, they are no longer allowed to have different
1810        names, because these cannot be distinguished in PCRE, and this has caused
1811        confusion. (This is a difference from Perl.)
1812    
1813    28. When duplicate subpattern names are present (necessarily with different
1814        numbers, as required by 27 above), and a test is made by name in a
1815        conditional pattern, either for a subpattern having been matched, or for
1816        recursion in such a pattern, all the associated numbered subpatterns are
1817        tested, and the overall condition is true if the condition is true for any
1818        one of them. This is the way Perl works, and is also more like the way
1819        testing by number works.
1820    
1821    
1822    Version 7.9 11-Apr-09
1823    ---------------------
1824    
1825    1.  When building with support for bzlib/zlib (pcregrep) and/or readline
1826        (pcretest), all targets were linked against these libraries. This included
1827        libpcre, libpcreposix, and libpcrecpp, even though they do not use these
1828        libraries. This caused unwanted dependencies to be created. This problem
1829        has been fixed, and now only pcregrep is linked with bzlib/zlib and only
1830        pcretest is linked with readline.
1831    
1832    2.  The "typedef int BOOL" in pcre_internal.h that was included inside the
1833        "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
1834        moved outside it again, because FALSE and TRUE are already defined in AIX,
1835        but BOOL is not.
1836    
1837    3.  The pcre_config() function was treating the PCRE_MATCH_LIMIT and
1838        PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
1839    
1840    4.  The pcregrep documentation said spaces were inserted as well as colons (or
1841        hyphens) following file names and line numbers when outputting matching
1842        lines. This is not true; no spaces are inserted. I have also clarified the
1843        wording for the --colour (or --color) option.
1844    
1845    5.  In pcregrep, when --colour was used with -o, the list of matching strings
1846        was not coloured; this is different to GNU grep, so I have changed it to be
1847        the same.
1848    
1849    6.  When --colo(u)r was used in pcregrep, only the first matching substring in
1850        each matching line was coloured. Now it goes on to look for further matches
1851        of any of the test patterns, which is the same behaviour as GNU grep.
1852    
1853    7.  A pattern that could match an empty string could cause pcregrep to loop; it
1854        doesn't make sense to accept an empty string match in pcregrep, so I have
1855        locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
1856        seems to be how GNU grep behaves. [But see later change 40 for release
1857        8.33.]
1858    
1859    8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
1860        start or after a newline", because the conditional assertion was not being
1861        correctly handled. The rule now is that both the assertion and what follows
1862        in the first alternative must satisfy the test.
1863    
1864    9.  If auto-callout was enabled in a pattern with a conditional group whose
1865        condition was an assertion, PCRE could crash during matching, both with
1866        pcre_exec() and pcre_dfa_exec().
1867    
1868    10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
1869        used for matching.
1870    
1871    11. Unicode property support in character classes was not working for
1872        characters (bytes) greater than 127 when not in UTF-8 mode.
1873    
1874    12. Added the -M command line option to pcretest.
1875    
1876    14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
1877    
1878    15. Added the PCRE_NO_START_OPTIMIZE match-time option.
1879    
1880    16. Added comments and documentation about mis-use of no_arg in the C++
1881        wrapper.
1882    
1883    17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
1884        from Martin Jerabek that uses macro names for all relevant character and
1885        string constants.
1886    
1887    18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
1888        SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
1889        SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
1890        these, but not everybody uses configure.
1891    
1892    19. A conditional group that had only one branch was not being correctly
1893        recognized as an item that could match an empty string. This meant that an
1894        enclosing group might also not be so recognized, causing infinite looping
1895        (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
1896        with the subject "ab", where knowledge that the repeated group can match
1897        nothing is needed in order to break the loop.
1898    
1899    20. If a pattern that was compiled with callouts was matched using pcre_dfa_
1900        exec(), but without supplying a callout function, matching went wrong.
1901    
1902    21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
1903        leak if the size of the offset vector was greater than 30. When the vector
1904        is smaller, the saved offsets during recursion go onto a local stack
1905        vector, but for larger vectors malloc() is used. It was failing to free
1906        when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
1907        error, in fact).
1908    
1909    22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
1910        heapframe that is used only when UTF-8 support is enabled. This caused no
1911        problem, but was untidy.
1912    
1913    23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
1914        CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
1915        included within another project.
1916    
1917    24. Steven Van Ingelgem's patches to add more options to the CMake support,
1918        slightly modified by me:
1919    
1920          (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
1921              not building pcregrep.
1922    
1923          (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
1924              if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
1925    
1926    25. Forward references, both numeric and by name, in patterns that made use of
1927        duplicate group numbers, could behave incorrectly or give incorrect errors,
1928        because when scanning forward to find the reference group, PCRE was not
1929        taking into account the duplicate group numbers. A pattern such as
1930        ^X(?3)(a)(?|(b)|(q))(Y) is an example.
1931    
1932    26. Changed a few more instances of "const unsigned char *" to USPTR, making
1933        the feature of a custom pointer more persuasive (as requested by a user).
1934    
1935    27. Wrapped the definitions of fileno and isatty for Windows, which appear in
1936        pcretest.c, inside #ifndefs, because it seems they are sometimes already
1937        pre-defined.
1938    
1939    28. Added support for (*UTF8) at the start of a pattern.
1940    
1941    29. Arrange for flags added by the "release type" setting in CMake to be shown
1942        in the configuration summary.
1943    
1944    
1945    Version 7.8 05-Sep-08
1946    ---------------------
1947    
1948    1.  Replaced UCP searching code with optimized version as implemented for Ad
1949        Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
1950        stage table and inline lookup instead of a function, giving speed ups of 2
1951        to 5 times on some simple patterns that I tested. Permission was given to
1952        distribute the MultiStage2.py script that generates the tables (it's not in
1953        the tarball, but is in the Subversion repository).
1954    
1955    2.  Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
1956        scripts.
1957    
1958    3.  Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
1959        a group with a zero qualifier. The result of the study could be incorrect,
1960        or the function might crash, depending on the pattern.
1961    
1962    4.  Caseless matching was not working for non-ASCII characters in back
1963        references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
1964        It now works when Unicode Property Support is available.
1965    
1966    5.  In pcretest, an escape such as \x{de} in the data was always generating
1967        a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
1968        non-UTF-8 mode. If the value is greater than 255, it gives a warning about
1969        truncation.
1970    
1971    6.  Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
1972    
1973    7.  Added two (int) casts to pcregrep when printing the difference of two
1974        pointers, in case they are 64-bit values.
1975    
1976    8.  Added comments about Mac OS X stack usage to the pcrestack man page and to
1977        test 2 if it fails.
1978    
1979    9.  Added PCRE_CALL_CONVENTION just before the names of all exported functions,
1980        and a #define of that name to empty if it is not externally set. This is to
1981        allow users of MSVC to set it if necessary.
1982    
1983    10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
1984        the convenience functions in the pcre_get.c source file.
1985    
1986    11. An option change at the start of a pattern that had top-level alternatives
1987        could cause overwriting and/or a crash. This command provoked a crash in
1988        some environments:
1989    
1990          printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
1991    
1992        This potential security problem was recorded as CVE-2008-2371.
1993    
1994    12. For a pattern where the match had to start at the beginning or immediately
1995        after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
1996        pcre_dfa_exec() could read past the end of the passed subject if there was
1997        no match. To help with detecting such bugs (e.g. with valgrind), I modified
1998        pcretest so that it places the subject at the end of its malloc-ed buffer.
1999    
2000    13. The change to pcretest in 12 above threw up a couple more cases when pcre_
2001        exec() might read past the end of the data buffer in UTF-8 mode.
2002    
2003    14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
2004        the data contained the byte 0x85 as part of a UTF-8 character within its
2005        first line. This applied both to normal and DFA matching.
2006    
2007    15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
2008        /^[^d]*?$/8 failed to match "abc".
2009    
2010    16. Added a missing copyright notice to pcrecpp_internal.h.
2011    
2012    17. Make it more clear in the documentation that values returned from
2013        pcre_exec() in ovector are byte offsets, not character counts.
2014    
2015    18. Tidied a few places to stop certain compilers from issuing warnings.
2016    
2017    19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
2018        supplied by Stefan Weber. I made a further small update for 7.8 because
2019        there is a change of source arrangements: the pcre_searchfuncs.c module is
2020        replaced by pcre_ucd.c.
2021    
2022    
2023    Version 7.7 07-May-08
2024    ---------------------
2025    
2026    1.  Applied Craig's patch to sort out a long long problem: "If we can't convert
2027        a string to a long long, pretend we don't even have a long long." This is
2028        done by checking for the strtoq, strtoll, and _strtoi64 functions.
2029    
2030    2.  Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
2031        pre-7.6 versions, which defined a global no_arg variable instead of putting
2032        it in the RE class. (See also #8 below.)
2033    
2034    3.  Remove a line of dead code, identified by coverity and reported by Nuno
2035        Lopes.
2036    
2037    4.  Fixed two related pcregrep bugs involving -r with --include or --exclude:
2038    
2039        (1) The include/exclude patterns were being applied to the whole pathnames
2040            of files, instead of just to the final components.
2041    
2042        (2) If there was more than one level of directory, the subdirectories were
2043            skipped unless they satisfied the include/exclude conditions. This is
2044            inconsistent with GNU grep (and could even be seen as contrary to the
2045            pcregrep specification - which I improved to make it absolutely clear).
2046            The action now is always to scan all levels of directory, and just
2047            apply the include/exclude patterns to regular files.
2048    
2049    5.  Added the --include_dir and --exclude_dir patterns to pcregrep, and used
2050        --exclude_dir in the tests to avoid scanning .svn directories.
2051    
2052    6.  Applied Craig's patch to the QuoteMeta function so that it escapes the
2053        NUL character as backslash + 0 rather than backslash + NUL, because PCRE
2054        doesn't support NULs in patterns.
2055    
2056    7.  Added some missing "const"s to declarations of static tables in
2057        pcre_compile.c and pcre_dfa_exec.c.
2058    
2059    8.  Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
2060        caused by fix #2  above. (Subsequently also a second patch to fix the
2061        first patch. And a third patch - this was a messy problem.)
2062    
2063    9.  Applied Craig's patch to remove the use of push_back().
2064    
2065    10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
2066        matching function regexec().
2067    
2068    11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
2069        which, however, unlike Perl's \g{...}, are subroutine calls, not back
2070        references. PCRE supports relative numbers with this syntax (I don't think
2071        Oniguruma does).
2072    
2073    12. Previously, a group with a zero repeat such as (...){0} was completely
2074        omitted from the compiled regex. However, this means that if the group
2075        was called as a subroutine from elsewhere in the pattern, things went wrong
2076        (an internal error was given). Such groups are now left in the compiled
2077        pattern, with a new opcode that causes them to be skipped at execution
2078        time.
2079    
2080    13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
2081        to the way PCRE behaves:
2082    
2083        (a) A lone ] character is dis-allowed (Perl treats it as data).
2084    
2085        (b) A back reference to an unmatched subpattern matches an empty string
2086            (Perl fails the current match path).
2087    
2088        (c) A data ] in a character class must be notated as \] because if the
2089            first data character in a class is ], it defines an empty class. (In
2090            Perl it is not possible to have an empty class.) The empty class []
2091            never matches; it forces failure and is equivalent to (*FAIL) or (?!).
2092            The negative empty class [^] matches any one character, independently
2093            of the DOTALL setting.
2094    
2095    14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
2096        non-existent subpattern following a character class starting with ']' and
2097        containing () gave an internal compiling error instead of "reference to
2098        non-existent subpattern". Fortunately, when the pattern did exist, the
2099        compiled code was correct. (When scanning forwards to check for the
2100        existence of the subpattern, it was treating the data ']' as terminating
2101        the class, so got the count wrong. When actually compiling, the reference
2102        was subsequently set up correctly.)
2103    
2104    15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
2105        it was being rejected as not supported by pcre_dfa_exec(), even though
2106        other assertions are supported. I have made pcre_dfa_exec() support
2107        (*FAIL).
2108    
2109    16. The implementation of 13c above involved the invention of a new opcode,
2110        OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
2111        cannot be changed at match time, I realized I could make a small
2112        improvement to matching performance by compiling OP_ALLANY instead of
2113        OP_ANY for "." when DOTALL was set, and then removing the runtime tests
2114        on the OP_ANY path.
2115    
2116    17. Compiling pcretest on Windows with readline support failed without the
2117        following two fixes: (1) Make the unistd.h include conditional on
2118        HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
2119    
2120    18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
2121        ncurses library to be included for pcretest when ReadLine support is
2122        requested, but also to allow for it to be overridden. This patch came from
2123        Daniel Bergström.
2124    
2125    19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
2126        as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
2127        any errors with the current Unicode tables. Thanks to Peter Kankowski for
2128        spotting this.
2129    
2130    
2131    Version 7.6 28-Jan-08
2132    ---------------------
2133    
2134    1.  A character class containing a very large number of characters with
2135        codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
2136        overflow.
2137    
2138    2.  Patch to cut out the "long long" test in pcrecpp_unittest when
2139        HAVE_LONG_LONG is not defined.
2140    
2141    3.  Applied Christian Ehrlicher's patch to update the CMake build files to
2142        bring them up to date and include new features. This patch includes:
2143    
2144        - Fixed PH's badly added libz and libbz2 support.
2145        - Fixed a problem with static linking.
2146        - Added pcredemo. [But later removed - see 7 below.]
2147        - Fixed dftables problem and added an option.
2148        - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
2149            HAVE_LONG_LONG.
2150        - Added readline support for pcretest.
2151        - Added an listing of the option settings after cmake has run.
2152    
2153    4.  A user submitted a patch to Makefile that makes it easy to create
2154        "pcre.dll" under mingw when using Configure/Make. I added stuff to
2155        Makefile.am that cause it to include this special target, without
2156        affecting anything else. Note that the same mingw target plus all
2157        the other distribution libraries and programs are now supported
2158        when configuring with CMake (see 6 below) instead of with
2159        Configure/Make.
2160    
2161    5.  Applied Craig's patch that moves no_arg into the RE class in the C++ code.
2162        This is an attempt to solve the reported problem "pcrecpp::no_arg is not
2163        exported in the Windows port". It has not yet been confirmed that the patch
2164        solves the problem, but it does no harm.
2165    
2166    6.  Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
2167        NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
2168        with CMake, and also correct the comment about stack recursion.
2169    
2170    7.  Remove the automatic building of pcredemo from the ./configure system and
2171        from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
2172        of a program that users should build themselves after PCRE is installed, so
2173        building it automatically is not really right. What is more, it gave
2174        trouble in some build environments.
2175    
2176    8.  Further tidies to CMakeLists.txt from Sheri and Christian.
2177    
2178    
2179    Version 7.5 10-Jan-08
2180    ---------------------
2181    
2182    1.  Applied a patch from Craig: "This patch makes it possible to 'ignore'
2183        values in parens when parsing an RE using the C++ wrapper."
2184    
2185    2.  Negative specials like \S did not work in character classes in UTF-8 mode.
2186        Characters greater than 255 were excluded from the class instead of being
2187        included.
2188    
2189    3.  The same bug as (2) above applied to negated POSIX classes such as
2190        [:^space:].
2191    
2192    4.  PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
2193        defined or documented. It seems to have been a typo for PCRE_STATIC, so
2194        I have changed it.
2195    
2196    5.  The construct (?&) was not diagnosed as a syntax error (it referenced the
2197        first named subpattern) and a construct such as (?&a) would reference the
2198        first named subpattern whose name started with "a" (in other words, the
2199        length check was missing). Both these problems are fixed. "Subpattern name
2200        expected" is now given for (?&) (a zero-length name), and this patch also
2201        makes it give the same error for \k'' (previously it complained that that
2202        was a reference to a non-existent subpattern).
2203    
2204    6.  The erroneous patterns (?+-a) and (?-+a) give different error messages;
2205        this is right because (?- can be followed by option settings as well as by
2206        digits. I have, however, made the messages clearer.
2207    
2208    7.  Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
2209        than the number used in the conditional) now cause a compile-time error.
2210        This is actually not compatible with Perl, which accepts such patterns, but
2211        treats the conditional as always being FALSE (as PCRE used to), but it
2212        seems to me that giving a diagnostic is better.
2213    
2214    8.  Change "alphameric" to the more common word "alphanumeric" in comments
2215        and messages.
2216    
2217    9.  Fix two occurrences of "backslash" in comments that should have been
2218        "backspace".
2219    
2220    10. Remove two redundant lines of code that can never be obeyed (their function
2221        was moved elsewhere).
2222    
2223    11. The program that makes PCRE's Unicode character property table had a bug
2224        which caused it to generate incorrect table entries for sequences of
2225        characters that have the same character type, but are in different scripts.
2226        It amalgamated them into a single range, with the script of the first of
2227        them. In other words, some characters were in the wrong script. There were
2228        thirteen such cases, affecting characters in the following ranges:
2229    
2230          U+002b0 - U+002c1
2231          U+0060c - U+0060d
2232          U+0061e - U+00612
2233          U+0064b - U+0065e
2234          U+0074d - U+0076d
2235          U+01800 - U+01805
2236          U+01d00 - U+01d77
2237          U+01d9b - U+01dbf
2238          U+0200b - U+0200f
2239          U+030fc - U+030fe
2240          U+03260 - U+0327f
2241          U+0fb46 - U+0fbb1
2242          U+10450 - U+1049d
2243    
2244    12. The -o option (show only the matching part of a line) for pcregrep was not
2245        compatible with GNU grep in that, if there was more than one match in a
2246        line, it showed only the first of them. It now behaves in the same way as
2247        GNU grep.
2248    
2249    13. If the -o and -v options were combined for pcregrep, it printed a blank
2250        line for every non-matching line. GNU grep prints nothing, and pcregrep now
2251        does the same. The return code can be used to tell if there were any
2252        non-matching lines.
2253    
2254    14. Added --file-offsets and --line-offsets to pcregrep.
2255    
2256    15. The pattern (?=something)(?R) was not being diagnosed as a potentially
2257        infinitely looping recursion. The bug was that positive lookaheads were not
2258        being skipped when checking for a possible empty match (negative lookaheads
2259        and both kinds of lookbehind were skipped).
2260    
2261    16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
2262        inclusion of <windows.h> to before rather than after the definition of
2263        INVALID_FILE_ATTRIBUTES (patch from David Byron).
2264    
2265    17. Specifying a possessive quantifier with a specific limit for a Unicode
2266        character property caused pcre_compile() to compile bad code, which led at
2267        runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
2268        are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
2269        caused the error; without that there was no problem.
2270    
2271    18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
2272    
2273    19. Added --enable-pcretest-libreadline.
2274    
2275    20. In pcrecpp.cc, the variable 'count' was incremented twice in
2276        RE::GlobalReplace(). As a result, the number of replacements returned was
2277        double what it should be. I removed one of the increments, but Craig sent a
2278        later patch that removed the other one (the right fix) and added unit tests
2279        that check the return values (which was not done before).
2280    
2281    21. Several CMake things:
2282    
2283        (1) Arranged that, when cmake is used on Unix, the libraries end up with
2284            the names libpcre and libpcreposix, not just pcre and pcreposix.
2285    
2286        (2) The above change means that pcretest and pcregrep are now correctly
2287            linked with the newly-built libraries, not previously installed ones.
2288    
2289        (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
2290    
2291    22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
2292        crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
2293        UTF-8 newline character). The key issue is that the pattern starts .*;
2294        this means that the match must be either at the beginning, or after a
2295        newline. The bug was in the code for advancing after a failed match and
2296        checking that the new position followed a newline. It was not taking
2297        account of UTF-8 characters correctly.
2298    
2299    23. PCRE was behaving differently from Perl in the way it recognized POSIX
2300        character classes. PCRE was not treating the sequence [:...:] as a
2301        character class unless the ... were all letters. Perl, however, seems to
2302        allow any characters between [: and :], though of course it rejects as
2303        unknown any "names" that contain non-letters, because all the known class
2304        names consist only of letters. Thus, Perl gives an error for [[:1234:]],
2305        for example, whereas PCRE did not - it did not recognize a POSIX character
2306        class. This seemed a bit dangerous, so the code has been changed to be
2307        closer to Perl. The behaviour is not identical to Perl, because PCRE will
2308        diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
2309        treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
2310        Perl does, and where it didn't before.
2311    
2312    24. Rewrite so as to remove the single use of %n from pcregrep because in some
2313        Windows environments %n is disabled by default.
2314    
2315    
2316    Version 7.4 21-Sep-07
2317    ---------------------
2318    
2319    1.  Change 7.3/28 was implemented for classes by looking at the bitmap. This
2320        means that a class such as [\s] counted as "explicit reference to CR or
2321        LF". That isn't really right - the whole point of the change was to try to
2322        help when there was an actual mention of one of the two characters. So now
2323        the change happens only if \r or \n (or a literal CR or LF) character is
2324        encountered.
2325    
2326    2.  The 32-bit options word was also used for 6 internal flags, but the numbers
2327        of both had grown to the point where there were only 3 bits left.
2328        Fortunately, there was spare space in the data structure, and so I have
2329        moved the internal flags into a new 16-bit field to free up more option
2330        bits.
2331    
2332    3.  The appearance of (?J) at the start of a pattern set the DUPNAMES option,
2333        but did not set the internal JCHANGED flag - either of these is enough to
2334        control the way the "get" function works - but the PCRE_INFO_JCHANGED
2335        facility is supposed to tell if (?J) was ever used, so now (?J) at the
2336        start sets both bits.
2337    
2338    4.  Added options (at build time, compile time, exec time) to change \R from
2339        matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
2340    
2341    5.  doc/pcresyntax.html was missing from the distribution.
2342    
2343    6.  Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
2344        compatibility, even though it is no longer used.
2345    
2346    7.  Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
2347        strtoull to pcrecpp.cc to select the available functions in WIN32 when the
2348        windows.h file is present (where different names are used). [This was
2349        reversed later after testing - see 16 below.]
2350    
2351    8.  Changed all #include <config.h> to #include "config.h". There were also
2352        some further <pcre.h> cases that I changed to "pcre.h".
2353    
2354    9.  When pcregrep was used with the --colour option, it missed the line ending
2355        sequence off the lines that it output.
2356    
2357    10. It was pointed out to me that arrays of string pointers cause lots of
2358        relocations when a shared library is dynamically loaded. A technique of
2359        using a single long string with a table of offsets can drastically reduce
2360        these. I have refactored PCRE in four places to do this. The result is
2361        dramatic:
2362    
2363          Originally:                          290
2364          After changing UCP table:            187
2365          After changing error message table:   43
2366          After changing table of "verbs"       36
2367          After changing table of Posix names   22
2368    
2369        Thanks to the folks working on Gregex for glib for this insight.
2370    
2371    11. --disable-stack-for-recursion caused compiling to fail unless -enable-
2372        unicode-properties was also set.
2373    
2374    12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
2375    
2376    13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
2377        checked only for CRLF.
2378    
2379    14. Added casts to pcretest.c to avoid compiler warnings.
2380    
2381    15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
2382    
2383    16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
2384        and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
2385        entirely. This removes changes made in 7 above.
2386    
2387    17. The CMake files have been updated, and there is now more information about
2388        building with CMake in the NON-UNIX-USE document.
2389    
2390    
2391    Version 7.3 28-Aug-07
2392  ---------------------  ---------------------
2393    
2394   1. In the rejigging of the build system that eventually resulted in 7.1, the   1. In the rejigging of the build system that eventually resulted in 7.1, the
# Line 9  Version 7.3 05-Jul-07 Line 2396  Version 7.3 05-Jul-07
2396      brackets there is not right, since it causes compilers to look for an      brackets there is not right, since it causes compilers to look for an
2397      installed pcre.h, not the version that is in the source that is being      installed pcre.h, not the version that is in the source that is being
2398      compiled (which of course may be different). I have changed it back to:      compiled (which of course may be different). I have changed it back to:
2399    
2400        #include "pcre.h"        #include "pcre.h"
2401    
2402      I have a vague recollection that the change was concerned with compiling in      I have a vague recollection that the change was concerned with compiling in
2403      different directories, but in the new build system, that is taken care of      different directories, but in the new build system, that is taken care of
2404      by the VPATH setting the Makefile.      by the VPATH setting the Makefile.
2405    
2406   2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed   2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
2407      when the subject happened to end in the byte 0x85 (e.g. if the last      when the subject happened to end in the byte 0x85 (e.g. if the last
2408      character was \x{1ec5}). *Character* 0x85 is one of the "any" newline      character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
# Line 23  Version 7.3 05-Jul-07 Line 2410  Version 7.3 05-Jul-07
2410      of another character. The bug was that, for an unlimited repeat of . in      of another character. The bug was that, for an unlimited repeat of . in
2411      not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by      not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
2412      characters when looking for a newline.      characters when looking for a newline.
   
  3. A small performance improvement in the DOTALL UTF-8 mode .* case.  
   
  4. Debugging: adjusted the names of opcodes for different kinds of parentheses  
     in debug output.  
   
  5. Arrange to use "%I64d" instead of "%lld" for long printing in the pcrecpp  
     unittest when running under MinGW.  
   
  6. ESC_K was left out of the EBCDIC table.  
2413    
2414     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
2415    
2416     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
2417        in debug output.
2418    
2419     5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
2420        long printing in the pcrecpp unittest when running under MinGW.
2421    
2422     6. ESC_K was left out of the EBCDIC table.
2423    
2424     7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
2425        parentheses; I made it 1000, which seemed large enough. Unfortunately, the
2426        limit also applies to "virtual nesting" when a pattern is recursive, and in
2427        this case 1000 isn't so big. I have been able to remove this limit at the
2428        expense of backing off one optimization in certain circumstances. Normally,
2429        when pcre_exec() would call its internal match() function recursively and
2430        immediately return the result unconditionally, it uses a "tail recursion"
2431        feature to save stack. However, when a subpattern that can match an empty
2432        string has an unlimited repetition quantifier, it no longer makes this
2433        optimization. That gives it a stack frame in which to save the data for
2434        checking that an empty string has been matched. Previously this was taken
2435        from the 1000-entry workspace that had been reserved. So now there is no
2436        explicit limit, but more stack is used.
2437    
2438     8. Applied Daniel's patches to solve problems with the import/export magic
2439        syntax that is required for Windows, and which was going wrong for the
2440        pcreposix and pcrecpp parts of the library. These were overlooked when this
2441        problem was solved for the main library.
2442    
2443     9. There were some crude static tests to avoid integer overflow when computing
2444        the size of patterns that contain repeated groups with explicit upper
2445        limits. As the maximum quantifier is 65535, the maximum group length was
2446        set at 30,000 so that the product of these two numbers did not overflow a
2447        32-bit integer. However, it turns out that people want to use groups that
2448        are longer than 30,000 bytes (though not repeat them that many times).
2449        Change 7.0/17 (the refactoring of the way the pattern size is computed) has
2450        made it possible to implement the integer overflow checks in a much more
2451        dynamic way, which I have now done. The artificial limitation on group
2452        length has been removed - we now have only the limit on the total length of
2453        the compiled pattern, which depends on the LINK_SIZE setting.
2454    
2455    10. Fixed a bug in the documentation for get/copy named substring when
2456        duplicate names are permitted. If none of the named substrings are set, the
2457        functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
2458        empty string.
2459    
2460    11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
2461        instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
2462        because the ] is interpreted as the first data character and the
2463        terminating ] is not found. PCRE has been made compatible with Perl in this
2464        regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
2465        cause memory overwriting.
2466    
2467    10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
2468        string has been matched (to stop an infinite loop). It was not recognizing
2469        a conditional subpattern that could match an empty string if that
2470        subpattern was within another subpattern. For example, it looped when
2471        trying to match  (((?(1)X|))*)  but it was OK with  ((?(1)X|)*)  where the
2472        condition was not nested. This bug has been fixed.
2473    
2474    12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
2475        past the start of the subject in the presence of bytes with the top bit
2476        set, for example "\x8aBCD".
2477    
2478    13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
2479        (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
2480    
2481    14. Optimized (?!) to (*FAIL).
2482    
2483    15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
2484        This restricts code points to be within the range 0 to 0x10FFFF, excluding
2485        the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
2486        full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
2487        does: it's just the validity check that is more restrictive.
2488    
2489    16. Inserted checks for integer overflows during escape sequence (backslash)
2490        processing, and also fixed erroneous offset values for syntax errors during
2491        backslash processing.
2492    
2493    17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
2494        for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
2495    
2496    18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
2497        caused an overrun.
2498    
2499    19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
2500        something other than just ASCII characters) inside a group that had an
2501        unlimited repeat caused a loop at compile time (while checking to see
2502        whether the group could match an empty string).
2503    
2504    20. Debugging a pattern containing \p or \P could cause a crash. For example,
2505        [\P{Any}] did so. (Error in the code for printing property names.)
2506    
2507    21. An orphan \E inside a character class could cause a crash.
2508    
2509    22. A repeated capturing bracket such as (A)? could cause a wild memory
2510        reference during compilation.
2511    
2512    23. There are several functions in pcre_compile() that scan along a compiled
2513        expression for various reasons (e.g. to see if it's fixed length for look
2514        behind). There were bugs in these functions when a repeated \p or \P was
2515        present in the pattern. These operators have additional parameters compared
2516        with \d, etc, and these were not being taken into account when moving along
2517        the compiled data. Specifically:
2518    
2519        (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
2520            length.
2521    
2522        (b) An item such as \pL+ within a repeated group could cause crashes or
2523            loops.
2524    
2525        (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
2526            "reference to non-existent subpattern" error.
2527    
2528        (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
2529    
2530    24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
2531        characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
2532    
2533    25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
2534    
2535    26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
2536        character were causing crashes (broken optimization).
2537    
2538    27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
2539        \p or \P) caused a compile-time loop.
2540    
2541    28. More problems have arisen in unanchored patterns when CRLF is a valid line
2542        break. For example, the unstudied pattern [\r\n]A does not match the string
2543        "\r\nA" because change 7.0/46 below moves the current point on by two
2544        characters after failing to match at the start. However, the pattern \nA
2545        *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
2546        the same is true. There doesn't seem any very clean way out of this, but
2547        what I have chosen to do makes the common cases work: PCRE now takes note
2548        of whether there can be an explicit match for \r or \n anywhere in the
2549        pattern, and if so, 7.0/46 no longer applies. As part of this change,
2550        there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
2551        pattern has explicit CR or LF references.
2552    
2553    29. Added (*CR) etc for changing newline setting at start of pattern.
2554    
2555    
2556  Version 7.2 19-Jun-07  Version 7.2 19-Jun-07

Legend:
Removed from v.195  
changed lines
  Added in v.1396

  ViewVC Help
Powered by ViewVC 1.1.5