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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.02 01-Mar-2010  Version 8.35 04-April-2014
5    --------------------------
6    
7    1.  A new flag is set, when property checks are present in an XCLASS.
8        When this flag is not set, PCRE can perform certain optimizations
9        such as studying these XCLASS-es.
10    
11    2.  The auto-possessification of character sets were improved: a normal
12        and an extended character set can be compared now. Furthermore
13        the JIT compiler optimizes more character set checks.
14    
15    3.  Got rid of some compiler warnings for potentially uninitialized variables
16        that show up only when compiled with -O2.
17    
18    4.  A pattern such as (?=ab\K) that uses \K in an assertion can set the start
19        of a match later then the end of the match. The pcretest program was not
20        handling the case sensibly - it was outputting from the start to the next
21        binary zero. It now reports this situation in a message, and outputs the
22        text from the end to the start.
23    
24    5.  Fast forward search is improved in JIT. Instead of the first three
25        characters, any three characters with fixed position can be searched.
26        Search order: first, last, middle.
27    
28    6.  Improve character range checks in JIT. Characters are read by an inprecise
29        function now, which returns with an unknown value if the character code is
30        above a certain treshold (e.g: 256). The only limitation is that the value
31        must be bigger than the treshold as well. This function is useful, when
32        the characters above the treshold are handled in the same way.
33    
34    7.  The macros whose names start with RAWUCHAR are placeholders for a future
35        mode in which only the bottom 21 bits of 32-bit data items are used. To
36        make this more memorable for those maintaining the code, the names have
37        been changed to start with UCHAR21, and an extensive comment has been added
38        to their definition.
39    
40    8.  Add missing (new) files sljitNativeTILEGX.c and sljitNativeTILEGX-encoder.c
41        to the export list in Makefile.am (they were accidentally omitted from the
42        8.34 tarball).
43    
44    9.  The informational output from pcretest used the phrase "starting byte set"
45        which is inappropriate for the 16-bit and 32-bit libraries. As the output
46        for "first char" and "need char" really means "non-UTF-char", I've changed
47        "byte" to "char", and slightly reworded the output. The documentation about
48        these values has also been (I hope) clarified.
49    
50    10. Another JIT related optimization: use table jumps for selecting the correct
51        backtracking path, when more than four alternatives are present inside a
52        bracket.
53    
54    11. Empty match is not possible, when the minimum length is greater than zero,
55        and there is no \K in the pattern. JIT should avoid empty match checks in
56        such cases.
57    
58    12. In a caseless character class with UCP support, when a character with more
59        than one alternative case was not the first character of a range, not all
60        the alternative cases were added to the class. For example, s and \x{17f}
61        are both alternative cases for S: the class [RST] was handled correctly,
62        but [R-T] was not.
63    
64    13. The configure.ac file always checked for pthread support when JIT was
65        enabled. This is not used in Windows, so I have put this test inside a
66        check for the presence of windows.h (which was already tested for).
67    
68    14. Improve pattern prefix search by a simplified Boyer-Moore algorithm in JIT.
69        The algorithm provides a way to skip certain starting offsets, and usually
70        faster than linear prefix searches.
71    
72    15. Change 13 for 8.20 updated RunTest to check for the 'fr' locale as well
73        as for 'fr_FR' and 'french'. For some reason, however, it then used the
74        Windows-specific input and output files, which have 'french' screwed in.
75        So this could never have worked. One of the problems with locales is that
76        they aren't always the same. I have now updated RunTest so that it checks
77        the output of the locale test (test 3) against three different output
78        files, and it allows the test to pass if any one of them matches. With luck
79        this should make the test pass on some versions of Solaris where it was
80        failing. Because of the uncertainty, the script did not used to stop if
81        test 3 failed; it now does. If further versions of a French locale ever
82        come to light, they can now easily be added.
83    
84    16. If --with-pcregrep-bufsize was given a non-integer value such as "50K",
85        there was a message during ./configure, but it did not stop. This now
86        provokes an error. The invalid example in README has been corrected.
87        If a value less than the minimum is given, the minimum value has always
88        been used, but now a warning is given.
89    
90    17. If --enable-bsr-anycrlf was set, the special 16/32-bit test failed. This
91        was a bug in the test system, which is now fixed. Also, the list of various
92        configurations that are tested for each release did not have one with both
93        16/32 bits and --enable-bar-anycrlf. It now does.
94    
95    18. pcretest was missing "-C bsr" for displaying the \R default setting.
96    
97    19. Little endian PowerPC systems are supported now by the JIT compiler.
98    
99    20. The fast forward newline mechanism could enter to an infinite loop on
100        certain invalid UTF-8 input. Although we don't support these cases
101        this issue can be fixed by a performance optimization.
102    
103    21. Change 33 of 8.34 is not sufficient to ensure stack safety because it does
104        not take account if existing stack usage. There is now a new global
105        variable called pcre_stack_guard that can be set to point to an external
106        function to check stack availability. It is called at the start of
107        processing every parenthesized group.
108    
109    22. A typo in the code meant that in ungreedy mode the max/min qualifier
110        behaved like a min-possessive qualifier, and, for example, /a{1,3}b/U did
111        not match "ab".
112    
113    23. When UTF was disabled, the JIT program reported some incorrect compile
114        errors. These messages are silenced now.
115    
116    24. Experimental support for ARM-64 and MIPS-64 has been added to the JIT
117        compiler.
118    
119    25. Change all the temporary files used in RunGrepTest to be different to those
120        used by RunTest so that the tests can be run simultaneously, for example by
121        "make -j check".
122    
123    
124    Version 8.34 15-December-2013
125    -----------------------------
126    
127    1.  Add pcre[16|32]_jit_free_unused_memory to forcibly free unused JIT
128        executable memory. Patch inspired by Carsten Klein.
129    
130    2.  ./configure --enable-coverage defined SUPPORT_GCOV in config.h, although
131        this macro is never tested and has no effect, because the work to support
132        coverage involves only compiling and linking options and special targets in
133        the Makefile. The comment in config.h implied that defining the macro would
134        enable coverage support, which is totally false. There was also support for
135        setting this macro in the CMake files (my fault, I just copied it from
136        configure). SUPPORT_GCOV has now been removed.
137    
138    3.  Make a small performance improvement in strlen16() and strlen32() in
139        pcretest.
140    
141    4.  Change 36 for 8.33 left some unreachable statements in pcre_exec.c,
142        detected by the Solaris compiler (gcc doesn't seem to be able to diagnose
143        these cases). There was also one in pcretest.c.
144    
145    5.  Cleaned up a "may be uninitialized" compiler warning in pcre_exec.c.
146    
147    6.  In UTF mode, the code for checking whether a group could match an empty
148        string (which is used for indefinitely repeated groups to allow for
149        breaking an infinite loop) was broken when the group contained a repeated
150        negated single-character class with a character that occupied more than one
151        data item and had a minimum repetition of zero (for example, [^\x{100}]* in
152        UTF-8 mode). The effect was undefined: the group might or might not be
153        deemed as matching an empty string, or the program might have crashed.
154    
155    7.  The code for checking whether a group could match an empty string was not
156        recognizing that \h, \H, \v, \V, and \R must match a character.
157    
158    8.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
159        an empty string. If it can, pcretest shows this in its information output.
160    
161    9.  Fixed two related bugs that applied to Unicode extended grapheme clusters
162        that were repeated with a maximizing qualifier (e.g. \X* or \X{2,5}) when
163        matched by pcre_exec() without using JIT:
164    
165        (a) If the rest of the pattern did not match after a maximal run of
166            grapheme clusters, the code for backing up to try with fewer of them
167            did not always back up over a full grapheme when characters that do not
168            have the modifier quality were involved, e.g. Hangul syllables.
169    
170        (b) If the match point in a subject started with modifier character, and
171            there was no match, the code could incorrectly back up beyond the match
172            point, and potentially beyond the first character in the subject,
173            leading to a segfault or an incorrect match result.
174    
175    10. A conditional group with an assertion condition could lead to PCRE
176        recording an incorrect first data item for a match if no other first data
177        item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
178        first data item, and therefore matched "ca" after "c" instead of at the
179        start.
180    
181    11. Change 40 for 8.33 (allowing pcregrep to find empty strings) showed up a
182        bug that caused the command "echo a | ./pcregrep -M '|a'" to loop.
183    
184    12. The source of pcregrep now includes z/OS-specific code so that it can be
185        compiled for z/OS as part of the special z/OS distribution.
186    
187    13. Added the -T and -TM options to pcretest.
188    
189    14. The code in pcre_compile.c for creating the table of named capturing groups
190        has been refactored. Instead of creating the table dynamically during the
191        actual compiling pass, the information is remembered during the pre-compile
192        pass (on the stack unless there are more than 20 named groups, in which
193        case malloc() is used) and the whole table is created before the actual
194        compile happens. This has simplified the code (it is now nearly 150 lines
195        shorter) and prepared the way for better handling of references to groups
196        with duplicate names.
197    
198    15. A back reference to a named subpattern when there is more than one of the
199        same name now checks them in the order in which they appear in the pattern.
200        The first one that is set is used for the reference. Previously only the
201        first one was inspected. This change makes PCRE more compatible with Perl.
202    
203    16. Unicode character properties were updated from Unicode 6.3.0.
204    
205    17. The compile-time code for auto-possessification has been refactored, based
206        on a patch by Zoltan Herczeg. It now happens after instead of during
207        compilation. The code is cleaner, and more cases are handled. The option
208        PCRE_NO_AUTO_POSSESS is added for testing purposes, and the -O and /O
209        options in pcretest are provided to set it. It can also be set by
210        (*NO_AUTO_POSSESS) at the start of a pattern.
211    
212    18. The character VT has been added to the default ("C" locale) set of
213        characters that match \s and are generally treated as white space,
214        following this same change in Perl 5.18. There is now no difference between
215        "Perl space" and "POSIX space". Whether VT is treated as white space in
216        other locales depends on the locale.
217    
218    19. The code for checking named groups as conditions, either for being set or
219        for being recursed, has been refactored (this is related to 14 and 15
220        above). Processing unduplicated named groups should now be as fast at
221        numerical groups, and processing duplicated groups should be faster than
222        before.
223    
224    20. Two patches to the CMake build system, by Alexander Barkov:
225    
226          (1) Replace the "source" command by "." in CMakeLists.txt because
227              "source" is a bash-ism.
228    
229          (2) Add missing HAVE_STDINT_H and HAVE_INTTYPES_H to config-cmake.h.in;
230              without these the CMake build does not work on Solaris.
231    
232    21. Perl has changed its handling of \8 and \9. If there is no previously
233        encountered capturing group of those numbers, they are treated as the
234        literal characters 8 and 9 instead of a binary zero followed by the
235        literals. PCRE now does the same.
236    
237    22. Following Perl, added \o{} to specify codepoints in octal, making it
238        possible to specify values greater than 0777 and also making them
239        unambiguous.
240    
241    23. Perl now gives an error for missing closing braces after \x{... instead of
242        treating the string as literal. PCRE now does the same.
243    
244    24. RunTest used to grumble if an inappropriate test was selected explicitly,
245        but just skip it when running all tests. This make it awkward to run ranges
246        of tests when one of them was inappropriate. Now it just skips any
247        inappropriate tests, as it always did when running all tests.
248    
249    25. If PCRE_AUTO_CALLOUT and PCRE_UCP were set for a pattern that contained
250        character types such as \d or \w, too many callouts were inserted, and the
251        data that they returned was rubbish.
252    
253    26. In UCP mode, \s was not matching two of the characters that Perl matches,
254        namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
255        were matched by \h. The code has now been refactored so that the lists of
256        the horizontal and vertical whitespace characters used for \h and \v (which
257        are defined only in one place) are now also used for \s.
258    
259    27. Add JIT support for the 64 bit TileGX architecture.
260        Patch by Jiong Wang (Tilera Corporation).
261    
262    28. Possessive quantifiers for classes (both explicit and automatically
263        generated) now use special opcodes instead of wrapping in ONCE brackets.
264    
265    29. Whereas an item such as A{4}+ ignored the possessivenes of the quantifier
266        (because it's meaningless), this was not happening when PCRE_CASELESS was
267        set. Not wrong, but inefficient.
268    
269    30. Updated perltest.pl to add /u (force Unicode mode) when /W (use Unicode
270        properties for \w, \d, etc) is present in a test regex. Otherwise if the
271        test contains no characters greater than 255, Perl doesn't realise it
272        should be using Unicode semantics.
273    
274    31. Upgraded the handling of the POSIX classes [:graph:], [:print:], and
275        [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
276        does in Unicode mode.
277    
278    32. Added the "forbid" facility to pcretest so that putting tests into the
279        wrong test files can sometimes be quickly detected.
280    
281    33. There is now a limit (default 250) on the depth of nesting of parentheses.
282        This limit is imposed to control the amount of system stack used at compile
283        time. It can be changed at build time by --with-parens-nest-limit=xxx or
284        the equivalent in CMake.
285    
286    34. Character classes such as [A-\d] or [a-[:digit:]] now cause compile-time
287        errors. Perl warns for these when in warning mode, but PCRE has no facility
288        for giving warnings.
289    
290    35. Change 34 for 8.13 allowed quantifiers on assertions, because Perl does.
291        However, this was not working for (?!) because it is optimized to (*FAIL),
292        for which PCRE does not allow quantifiers. The optimization is now disabled
293        when a quantifier follows (?!). I can't see any use for this, but it makes
294        things uniform.
295    
296    36. Perl no longer allows group names to start with digits, so I have made this
297        change also in PCRE. It simplifies the code a bit.
298    
299    37. In extended mode, Perl ignores spaces before a + that indicates a
300        possessive quantifier. PCRE allowed a space before the quantifier, but not
301        before the possessive +. It now does.
302    
303    38. The use of \K (reset reported match start) within a repeated possessive
304        group such as (a\Kb)*+ was not working.
305    
306    40. Document that the same character tables must be used at compile time and
307        run time, and that the facility to pass tables to pcre_exec() and
308        pcre_dfa_exec() is for use only with saved/restored patterns.
309    
310    41. Applied Jeff Trawick's patch CMakeLists.txt, which "provides two new
311        features for Builds with MSVC:
312    
313        1. Support pcre.rc and/or pcreposix.rc (as is already done for MinGW
314           builds). The .rc files can be used to set FileDescription and many other
315           attributes.
316    
317        2. Add an option (-DINSTALL_MSVC_PDB) to enable installation of .pdb files.
318           This allows higher-level build scripts which want .pdb files to avoid
319           hard-coding the exact files needed."
320    
321    42. Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
322        mean "start of word" and "end of word", respectively, as a transition aid.
323    
324    43. A minimizing repeat of a class containing codepoints greater than 255 in
325        non-UTF 16-bit or 32-bit modes caused an internal error when PCRE was
326        compiled to use the heap for recursion.
327    
328    44. Got rid of some compiler warnings for unused variables when UTF but not UCP
329        is configured.
330    
331    
332    Version 8.33 28-May-2013
333    ------------------------
334    
335    1.  Added 'U' to some constants that are compared to unsigned integers, to
336        avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
337        variables that are added to signed variables, to ensure the result is
338        signed and can be negated.
339    
340    2.  Applied patch by Daniel Richard G for quashing MSVC warnings to the
341        CMake config files.
342    
343    3.  Revise the creation of config.h.generic so that all boolean macros are
344        #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
345        overriding via -D on the command line possible.
346    
347    4.  Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
348        to unsigned int is reported to make a quite noticeable speed difference in
349        a specific Windows environment. Testing on Linux did also appear to show
350        some benefit (and it is clearly not harmful). Also fixed the definition of
351        Xop which should be unsigned.
352    
353    5.  Related to (4), changing the definition of the intermediate variable cc
354        in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
355        improvements.
356    
357    6.  Fix forward search in JIT when link size is 3 or greater. Also removed some
358        unnecessary spaces.
359    
360    7.  Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
361        and later.
362    
363    8.  Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
364    
365    9.  Optimizing fast_forward_start_bits in JIT.
366    
367    10. Adding support for callouts in JIT, and fixing some issues revealed
368        during this work. Namely:
369    
370        (a) Unoptimized capturing brackets incorrectly reset on backtrack.
371    
372        (b) Minimum length was not checked before the matching is started.
373    
374    11. The value of capture_last that is passed to callouts was incorrect in some
375        cases when there was a capture on one path that was subsequently abandoned
376        after a backtrack. Also, the capture_last value is now reset after a
377        recursion, since all captures are also reset in this case.
378    
379    12. The interpreter no longer returns the "too many substrings" error in the
380        case when an overflowing capture is in a branch that is subsequently
381        abandoned after a backtrack.
382    
383    13. In the pathological case when an offset vector of size 2 is used, pcretest
384        now prints out the matched string after a yield of 0 or 1.
385    
386    14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
387        Only supported by the JIT compiler at the moment.
388    
389    15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
390    
391    16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
392        offset of the starting point of the matching process, provided the offsets
393        vector is large enough.
394    
395    17. The \A escape now records a lookbehind value of 1, though its execution
396        does not actually inspect the previous character. This is to ensure that,
397        in partial multi-segment matching, at least one character from the old
398        segment is retained when a new segment is processed. Otherwise, if there
399        are no lookbehinds in the pattern, \A might match incorrectly at the start
400        of a new segment.
401    
402    18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
403    
404    19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
405        gives some modest performance improvement in 8-bit mode.
406    
407    20. Added the PCRE-specific property \p{Xuc} for matching characters that can
408        be expressed in certain programming languages using Universal Character
409        Names.
410    
411    21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
412        which points out that "non characters" are not "characters that may not
413        appear in Unicode strings" but rather "characters that are reserved for
414        internal use and have only local meaning".
415    
416    22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
417        there was a conditional group that depended on an assertion, if the
418        assertion was false, the callout that immediately followed the alternation
419        in the condition was skipped when pcre_exec() was used for matching.
420    
421    23. Allow an explicit callout to be inserted before an assertion that is the
422        condition for a conditional group, for compatibility with automatic
423        callouts, which always insert a callout at this point.
424    
425    24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
426        confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
427    
428    25. (*PRUNE) is now supported by the JIT compiler.
429    
430    26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
431    
432    27. Fix the case where there are two or more SKIPs with arguments that may be
433        ignored.
434    
435    28. (*SKIP) is now supported by the JIT compiler.
436    
437    29. (*THEN) is now supported by the JIT compiler.
438    
439    30. Update RunTest with additional test selector options.
440    
441    31. The way PCRE handles backtracking verbs has been changed in two ways.
442    
443        (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
444        SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
445        backtracking. In some cases this makes it more Perl-compatible, but Perl's
446        rather obscure rules do not always do the same thing.
447    
448        (2) Previously, backtracking verbs were confined within assertions. This is
449        no longer the case for positive assertions, except for (*ACCEPT). Again,
450        this sometimes improves Perl compatibility, and sometimes does not.
451    
452    32. A number of tests that were in test 2 because Perl did things differently
453        have been moved to test 1, because either Perl or PCRE has changed, and
454        these tests are now compatible.
455    
456    32. Backtracking control verbs are now handled in the same way in JIT and
457        interpreter.
458    
459    33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
460        contained a forward subroutine reference caused a compile error.
461    
462    34. Auto-detect and optimize limited repetitions in JIT.
463    
464    35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
465        blocking (*UTF) etc.
466    
467    36. In the interpreter, maximizing pattern repetitions for characters and
468        character types now use tail recursion, which reduces stack usage.
469    
470    37. The value of the max lookbehind was not correctly preserved if a compiled
471        and saved regex was reloaded on a host of different endianness.
472    
473    38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
474        of the compiled pattern block, expand the flags field from 16 to 32 bits
475        because it was almost full.
476    
477    39. Try madvise first before posix_madvise.
478    
479    40. Change 7 for PCRE 7.9 made it impossible for pcregrep to find empty lines
480        with a pattern such as ^$. It has taken 4 years for anybody to notice! The
481        original change locked out all matches of empty strings. This has been
482        changed so that one match of an empty string per line is recognized.
483        Subsequent searches on the same line (for colouring or for --only-matching,
484        for example) do not recognize empty strings.
485    
486    41. Applied a user patch to fix a number of spelling mistakes in comments.
487    
488    42. Data lines longer than 65536 caused pcretest to crash.
489    
490    43. Clarified the data type for length and startoffset arguments for pcre_exec
491        and pcre_dfa_exec in the function-specific man pages, where they were
492        explicitly stated to be in bytes, never having been updated. I also added
493        some clarification to the pcreapi man page.
494    
495    44. A call to pcre_dfa_exec() with an output vector size less than 2 caused
496        a segmentation fault.
497    
498    
499    Version 8.32 30-November-2012
500    -----------------------------
501    
502    1.  Improved JIT compiler optimizations for first character search and single
503        character iterators.
504    
505    2.  Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
506        Patch by Daniel Richard G.
507    
508    3.  Single character iterator optimizations in the JIT compiler.
509    
510    4.  Improved JIT compiler optimizations for character ranges.
511    
512    5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
513        Reported by Giuseppe D'Angelo.
514    
515    6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
516        of a line, was being set incorrectly in cases where .* appeared inside
517        atomic brackets at the start of a pattern, or where there was a subsequent
518        *PRUNE or *SKIP.
519    
520    7.  Improved instruction cache flush for POWER/PowerPC.
521        Patch by Daniel Richard G.
522    
523    8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
524        grep:
525    
526        (a) There is now no limit to the number of patterns to be matched.
527    
528        (b) An error is given if a pattern is too long.
529    
530        (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
531            are now supported.
532    
533        (d) --exclude-from and --include-from (multiple use) have been added.
534    
535        (e) Exclusions and inclusions now apply to all files and directories, not
536            just to those obtained from scanning a directory recursively.
537    
538        (f) Multiple uses of -f and --file-list are now supported.
539    
540        (g) In a Windows environment, the default for -d has been changed from
541            "read" (the GNU grep default) to "skip", because otherwise the presence
542            of a directory in the file list provokes an error.
543    
544        (h) The documentation has been revised and clarified in places.
545    
546    9.  Improve the matching speed of capturing brackets.
547    
548    10. Changed the meaning of \X so that it now matches a Unicode extended
549        grapheme cluster.
550    
551    11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
552        out POSIX threads when JIT support is configured.
553    
554    12. Added support for PCRE_STUDY_EXTRA_NEEDED.
555    
556    13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
557        structure could go wrong in environments where size_t is not the same size
558        as int.
559    
560    14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
561        set.
562    
563    15. The EBCDIC support had decayed; later updates to the code had included
564        explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
565        general tidy up of EBCDIC-related issues, and the documentation was also
566        not quite right. There is now a test that can be run on ASCII systems to
567        check some of the EBCDIC-related things (but is it not a full test).
568    
569    16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
570        in a small tidy to the code.
571    
572    17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
573    
574    18. If the --only-matching (-o) option in pcregrep is specified multiple
575        times, each one causes appropriate output. For example, -o1 -o2 outputs the
576        substrings matched by the 1st and 2nd capturing parentheses. A separating
577        string can be specified by --om-separator (default empty).
578    
579    19. Improving the first n character searches.
580    
581    20. Turn case lists for horizontal and vertical white space into macros so that
582        they are defined only once.
583    
584    21. This set of changes together give more compatible Unicode case-folding
585        behaviour for characters that have more than one other case when UCP
586        support is available.
587    
588        (a) The Unicode property table now has offsets into a new table of sets of
589            three or more characters that are case-equivalent. The MultiStage2.py
590            script that generates these tables (the pcre_ucd.c file) now scans
591            CaseFolding.txt instead of UnicodeData.txt for character case
592            information.
593    
594        (b) The code for adding characters or ranges of characters to a character
595            class has been abstracted into a generalized function that also handles
596            case-independence. In UTF-mode with UCP support, this uses the new data
597            to handle characters with more than one other case.
598    
599        (c) A bug that is fixed as a result of (b) is that codepoints less than 256
600            whose other case is greater than 256 are now correctly matched
601            caselessly. Previously, the high codepoint matched the low one, but not
602            vice versa.
603    
604        (d) The processing of \h, \H, \v, and \ in character classes now makes use
605            of the new class addition function, using character lists defined as
606            macros alongside the case definitions of 20 above.
607    
608        (e) Caseless back references now work with characters that have more than
609            one other case.
610    
611        (f) General caseless matching of characters with more than one other case
612            is supported.
613    
614    22. Unicode character properties were updated from Unicode 6.2.0
615    
616    23. Improved CMake support under Windows. Patch by Daniel Richard G.
617    
618    24. Add support for 32-bit character strings, and UTF-32
619    
620    25. Major JIT compiler update (code refactoring and bugfixing).
621        Experimental Sparc 32 support is added.
622    
623    26. Applied a modified version of Daniel Richard G's patch to create
624        pcre.h.generic and config.h.generic by "make" instead of in the
625        PrepareRelease script.
626    
627    27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
628        pcre_compile.c when checking for a zero character.
629    
630    28. Introducing a native interface for JIT. Through this interface, the compiled
631        machine code can be directly executed. The purpose of this interface is to
632        provide fast pattern matching, so several sanity checks are not performed.
633        However, feature tests are still performed. The new interface provides
634        1.4x speedup compared to the old one.
635    
636    29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
637        the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
638        was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
639    
640    30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
641        greater than 0x7fffffff (which cannot be represented in UTF-8, even under
642        the "old" RFC 2279). Instead, it ended up passing a negative length to
643        pcre_exec().
644    
645    31. Add support for GCC's visibility feature to hide internal functions.
646    
647    32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
648        "unknown -C option" after outputting 0 or 1.
649    
650    33. There is now support for generating a code coverage report for the test
651        suite in environments where gcc is the compiler and lcov is installed. This
652        is mainly for the benefit of the developers.
653    
654    34. If PCRE is built with --enable-valgrind, certain memory regions are marked
655        unaddressable using valgrind annotations, allowing valgrind to detect
656        invalid memory accesses. This is mainly for the benefit of the developers.
657    
658    25. (*UTF) can now be used to start a pattern in any of the three libraries.
659    
660    26. Give configure error if --enable-cpp but no C++ compiler found.
661    
662    
663    Version 8.31 06-July-2012
664    -------------------------
665    
666    1.  Fixing a wrong JIT test case and some compiler warnings.
667    
668    2.  Removed a bashism from the RunTest script.
669    
670    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
671        to unsigned type, result still unsigned" that was given by an MS compiler
672        on encountering the code "-sizeof(xxx)".
673    
674    4.  Partial matching support is added to the JIT compiler.
675    
676    5.  Fixed several bugs concerned with partial matching of items that consist
677        of more than one character:
678    
679        (a) /^(..)\1/ did not partially match "aba" because checking references was
680            done on an "all or nothing" basis. This also applied to repeated
681            references.
682    
683        (b) \R did not give a hard partial match if \r was found at the end of the
684            subject.
685    
686        (c) \X did not give a hard partial match after matching one or more
687            characters at the end of the subject.
688    
689        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
690            a partial match for the string "\r".
691    
692        (e) When newline was set to CRLF, the metacharacter "." did not recognize
693            a partial match for a CR character at the end of the subject string.
694    
695    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
696        running pcretest, the text "(JIT)" added to the output whenever JIT is
697        actually used to run the match.
698    
699    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
700        or /S+[+] with a digit between 1 and 7.
701    
702    8.  OP_NOT now supports any UTF character not just single-byte ones.
703    
704    9.  (*MARK) control verb is now supported by the JIT compiler.
705    
706    10. The command "./RunTest list" lists the available tests without actually
707        running any of them. (Because I keep forgetting what they all are.)
708    
709    11. Add PCRE_INFO_MAXLOOKBEHIND.
710    
711    12. Applied a (slightly modified) user-supplied patch that improves performance
712        when the heap is used for recursion (compiled with --disable-stack-for-
713        recursion). Instead of malloc and free for each heap frame each time a
714        logical recursion happens, frames are retained on a chain and re-used where
715        possible. This sometimes gives as much as 30% improvement.
716    
717    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
718        call.
719    
720    14. As documented, (*COMMIT) is now confined to within a positive assertion.
721    
722    15. It is now possible to link pcretest with libedit as an alternative to
723        libreadline.
724    
725    16. (*COMMIT) control verb is now supported by the JIT compiler.
726    
727    17. The Unicode data tables have been updated to Unicode 6.1.0.
728    
729    18. Added --file-list option to pcregrep.
730    
731    19. Added binary file support to pcregrep, including the -a, --binary-files,
732        -I, and --text options.
733    
734    20. The madvise function is renamed for posix_madvise for QNX compatibility
735        reasons. Fixed by Giuseppe D'Angelo.
736    
737    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
738    
739    22. Changed the option for creating symbolic links for 16-bit man pages from
740        -s to -sf so that re-installing does not cause issues.
741    
742    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
743    
744    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
745        matches in certain environments (the workspace was not being correctly
746        retained). Also added to pcre_dfa_exec() a simple plausibility check on
747        some of the workspace data at the beginning of a restart.
748    
749    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
750        was not doing so when it should - probably a typo introduced by SVN 528
751        (change 8.10/14).
752    
753    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
754        \w+ when the character tables indicated that \x{c4} was a word character.
755        There were several related cases, all because the tests for doing a table
756        lookup were testing for characters less than 127 instead of 255.
757    
758    27. If a pattern contains capturing parentheses that are not used in a match,
759        their slots in the ovector are set to -1. For those that are higher than
760        any matched groups, this happens at the end of processing. In the case when
761        there were back references that the ovector was too small to contain
762        (causing temporary malloc'd memory to be used during matching), and the
763        highest capturing number was not used, memory off the end of the ovector
764        was incorrectly being set to -1. (It was using the size of the temporary
765        memory instead of the true size.)
766    
767    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
768        ovector size, it uses memory at the end of the block that it has got.
769    
770    29. Check for an overlong MARK name and give an error at compile time. The
771        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
772    
773    30. JIT compiler update.
774    
775    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
776        Rill for the patch.
777    
778    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
779    
780    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
781    
782    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
783        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
784        was enabled.
785    
786    35. Improve JIT code generation for greedy plus quantifier.
787    
788    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
789        1 to "aa" instead of to an empty string. The bug affected repeated groups
790        that could potentially match an empty string.
791    
792    37. Optimizing single character iterators in JIT.
793    
794    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
795        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
796        codepoints that are too big for the mode are faulted, and in a UTF mode,
797        disallowed codepoints are also faulted.
798    
799    39. If PCRE was compiled with UTF support, in three places in the DFA
800        matcher there was code that should only have been obeyed in UTF mode, but
801        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
802        processing when bytes with values greater than 127 were present. In 16-bit
803        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
804        both cases the values are those that cannot be the first data item in a UTF
805        character. The three items that might have provoked this were recursions,
806        possessively repeated groups, and atomic groups.
807    
808    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
809        and pcregrep, because some OS require shared objects to be explicitly
810        passed to ld, causing the link step to fail if they are not.
811    
812    41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
813        mode, patterns that started with \h* or \R* might be incorrectly matched.
814    
815    
816    Version 8.30 04-February-2012
817    -----------------------------
818    
819    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
820        name is defined in ctype.h.
821    
822    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
823        only in quite long subpatterns.
824    
825    3.  Removed the function pcre_info(), which has been obsolete and deprecated
826        since it was replaced by pcre_fullinfo() in February 2000.
827    
828    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
829        match a (*MARK), and the match failed at the start of the subject, a
830        reference to memory before the start of the subject could occur. This bug
831        was introduced by fix 17 of release 8.21.
832    
833    5.  A reference to an unset group with zero minimum repetition was giving
834        totally wrong answers (in non-JavaScript-compatibility mode). For example,
835        /(another)?(\1?)test/ matched against "hello world test". This bug was
836        introduced in release 8.13.
837    
838    6.  Add support for 16-bit character strings (a large amount of work involving
839        many changes and refactorings).
840    
841    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
842        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
843        from a file.
844    
845    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
846        rounding is not applied in this particular case).
847    
848    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
849        if they appear, or are escaped, in patterns.
850    
851    10. Get rid of a number of -Wunused-but-set-variable warnings.
852    
853    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
854        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
855        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
856        also returns the mark "x". This bug applied to capturing parentheses,
857        non-capturing parentheses, and atomic parentheses. It also applied to some
858        assertions.
859    
860    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
861        information out of configure.ac instead of relying on pcre.h.generic, which
862        is not stored in the repository.
863    
864    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
865        -lreadline.
866    
867    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
868    
869    15. Applied Graycode's patch to put the top-level frame on the stack rather
870        than the heap when not using the stack for recursion. This gives a
871        performance improvement in many cases when recursion is not deep.
872    
873    16. Experimental code added to "pcretest -C" to output the stack frame size.
874    
875    
876    Version 8.21 12-Dec-2011
877    ------------------------
878    
879    1.  Updating the JIT compiler.
880    
881    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
882        are added as well.
883    
884    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
885        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
886        calling _pcre_jit_exec. Some extra comments are added.
887    
888    4.  (*MARK) settings inside atomic groups that do not contain any capturing
889        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
890        was introduced by change 18 for 8.20.
891    
892    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
893        ECMA-262 standard.
894    
895    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
896        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
897        This bug was probably introduced by change 9 of 8.13.
898    
899    7.  While fixing 6 above, I noticed that a number of other items were being
900        incorrectly rejected as "not fixed length". This arose partly because newer
901        opcodes had not been added to the fixed-length checking code. I have (a)
902        corrected the bug and added tests for these items, and (b) arranged for an
903        error to occur if an unknown opcode is encountered while checking for fixed
904        length instead of just assuming "not fixed length". The items that were
905        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
906        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
907        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
908    
909    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
910        being incorrectly compiled and would have given unpredicatble results.
911    
912    9.  A possessively repeated subpattern with minimum repeat count greater than
913        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
914        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
915        the first (A) could occur when it should not.
916    
917    10. Add a cast and remove a redundant test from the code.
918    
919    11. JIT should use pcre_malloc/pcre_free for allocation.
920    
921    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
922        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
923        is anything other than /usr, -L is still shown).
924    
925    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
926    
927    14. Perl does not support \N without a following name in a [] class; PCRE now
928        also gives an error.
929    
930    15. If a forward reference was repeated with an upper limit of around 2000,
931        it caused the error "internal error: overran compiling workspace". The
932        maximum number of forward references (including repeats) was limited by the
933        internal workspace, and dependent on the LINK_SIZE. The code has been
934        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
935        the default depends on LINK_SIZE. There is a new upper limit (for safety)
936        of around 200,000 forward references. While doing this, I also speeded up
937        the filling in of repeated forward references.
938    
939    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
940        incorrectly expecting the subject to contain another "a" after the start.
941    
942    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
943        in the match, the SKIP should be ignored. This was not happening; instead
944        the SKIP was being treated as NOMATCH. For patterns such as
945        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
946        tested.
947    
948    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
949        now much more compatible with Perl, in particular in cases where the result
950        is a non-match for a non-anchored pattern. For example, if
951        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
952        "m", where previously it did not return a name. A side effect of this
953        change is that for partial matches, the last encountered mark name is
954        returned, as for non matches. A number of tests that were previously not
955        Perl-compatible have been moved into the Perl-compatible test files. The
956        refactoring has had the pleasing side effect of removing one argument from
957        the match() function, thus reducing its stack requirements.
958    
959    19. If the /S+ option was used in pcretest to study a pattern using JIT,
960        subsequent uses of /S (without +) incorrectly behaved like /S+.
961    
962    21. Retrieve executable code size support for the JIT compiler and fixing
963        some warnings.
964    
965    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
966        not work when the shorter character appeared right at the end of the
967        subject string.
968    
969    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
970        systems.
971    
972    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
973        output it when the /M option is used in pcretest.
974    
975    25. The CheckMan script was not being included in the distribution. Also, added
976        an explicit "perl" to run Perl scripts from the PrepareRelease script
977        because this is reportedly needed in Windows.
978    
979    26. If study data was being save in a file and studying had not found a set of
980        "starts with" bytes for the pattern, the data written to the file (though
981        never used) was taken from uninitialized memory and so caused valgrind to
982        complain.
983    
984    27. Updated RunTest.bat as provided by Sheri Pierce.
985    
986    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
987    
988    29. Computation of memory usage for the table of capturing group names was
989        giving an unnecessarily large value.
990    
991    
992    Version 8.20 21-Oct-2011
993    ------------------------
994    
995    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
996        a POSIX class. After further experiments with Perl, which convinced me that
997        Perl has bugs and confusions, a closing square bracket is no longer allowed
998        in a POSIX name. This bug also affected patterns with classes that started
999        with full stops.
1000    
1001    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
1002        captured substring, but while checking the failing first alternative,
1003        substring 1 is temporarily captured. If the output vector supplied to
1004        pcre_exec() was not big enough for this capture, the yield of the function
1005        was still zero ("insufficient space for captured substrings"). This cannot
1006        be totally fixed without adding another stack variable, which seems a lot
1007        of expense for a edge case. However, I have improved the situation in cases
1008        such as /(a)(b)x|abc/ matched against "abc", where the return code
1009        indicates that fewer than the maximum number of slots in the ovector have
1010        been set.
1011    
1012    3.  Related to (2) above: when there are more back references in a pattern than
1013        slots in the output vector, pcre_exec() uses temporary memory during
1014        matching, and copies in the captures as far as possible afterwards. It was
1015        using the entire output vector, but this conflicts with the specification
1016        that only 2/3 is used for passing back captured substrings. Now it uses
1017        only the first 2/3, for compatibility. This is, of course, another edge
1018        case.
1019    
1020    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
1021        main code base, and can be used by building with --enable-jit. When this is
1022        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
1023        runtime --no-jit option is given.
1024    
1025    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
1026        ovector, the return from the function was zero, implying that there were
1027        other matches that did not fit. The correct "exactly full" value is now
1028        returned.
1029    
1030    6.  If a subpattern that was called recursively or as a subroutine contained
1031        (*PRUNE) or any other control that caused it to give a non-standard return,
1032        invalid errors such as "Error -26 (nested recursion at the same subject
1033        position)" or even infinite loops could occur.
1034    
1035    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
1036        computing the minimum length on reaching *ACCEPT, and so ended up with the
1037        wrong value of 1 rather than 0. Further investigation indicates that
1038        computing a minimum subject length in the presence of *ACCEPT is difficult
1039        (think back references, subroutine calls), and so I have changed the code
1040        so that no minimum is registered for a pattern that contains *ACCEPT.
1041    
1042    8.  If (*THEN) was present in the first (true) branch of a conditional group,
1043        it was not handled as intended. [But see 16 below.]
1044    
1045    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
1046        Sheri Pierce.
1047    
1048    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
1049        the first byte in a match must be "a".
1050    
1051    11. Change 17 for 8.13 increased the recursion depth for patterns like
1052        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
1053        pattern contains any instances of (*THEN). If it does not, the old
1054        optimizations are restored. It would be nice to do this on a per-group
1055        basis, but at the moment that is not feasible.
1056    
1057    12. In some environments, the output of pcretest -C is CRLF terminated. This
1058        broke RunTest's code that checks for the link size. A single white space
1059        character after the value is now allowed for.
1060    
1061    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
1062        For "fr", it uses the Windows-specific input and output files.
1063    
1064    14. If (*THEN) appeared in a group that was called recursively or as a
1065        subroutine, it did not work as intended. [But see next item.]
1066    
1067    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
1068        pattern fragments (but not containing any | characters). If A and B are
1069        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
1070        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
1071        D. In other words, Perl considers parentheses that do not contain any |
1072        characters to be part of a surrounding alternative, whereas PCRE was
1073        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
1074        differently. PCRE now behaves in the same way as Perl, except in the case
1075        of subroutine/recursion calls such as (?1) which have in any case always
1076        been different (but PCRE had them first :-).
1077    
1078    16. Related to 15 above: Perl does not treat the | in a conditional group as
1079        creating alternatives. Such a group is treated in the same way as an
1080        ordinary group without any | characters when processing (*THEN). PCRE has
1081        been changed to match Perl's behaviour.
1082    
1083    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
1084        RunGrepTest script failed.
1085    
1086    18. Change 22 for version 13 caused atomic groups to use more stack. This is
1087        inevitable for groups that contain captures, but it can lead to a lot of
1088        stack use in large patterns. The old behaviour has been restored for atomic
1089        groups that do not contain any capturing parentheses.
1090    
1091    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
1092        suppress the check for a minimum subject length at run time. (If it was
1093        given to pcre_exec() or pcre_dfa_exec() it did work.)
1094    
1095    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
1096        fail to work when decoding hex characters in data strings in EBCDIC
1097        environments.
1098    
1099    21. It appears that in at least one Mac OS environment, the isxdigit() function
1100        is implemented as a macro that evaluates to its argument more than once,
1101        contravening the C 90 Standard (I haven't checked a later standard). There
1102        was an instance in pcretest which caused it to go wrong when processing
1103        \x{...} escapes in subject strings. The has been rewritten to avoid using
1104        things like p++ in the argument of isxdigit().
1105    
1106    
1107    Version 8.13 16-Aug-2011
1108    ------------------------
1109    
1110    1.  The Unicode data tables have been updated to Unicode 6.0.0.
1111    
1112    2.  Two minor typos in pcre_internal.h have been fixed.
1113    
1114    3.  Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
1115        pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
1116        in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
1117    
1118    4.  There were a number of related bugs in the code for matching backrefences
1119        caselessly in UTF-8 mode when codes for the characters concerned were
1120        different numbers of bytes. For example, U+023A and U+2C65 are an upper
1121        and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
1122        (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
1123        code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
1124        2-byte code at the end of the subject (it thought there wasn't enough data
1125        left).
1126    
1127    5.  Comprehensive information about what went wrong is now returned by
1128        pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
1129        as the output vector has at least 2 elements. The offset of the start of
1130        the failing character and a reason code are placed in the vector.
1131    
1132    6.  When the UTF-8 string check fails for pcre_compile(), the offset that is
1133        now returned is for the first byte of the failing character, instead of the
1134        last byte inspected. This is an incompatible change, but I hope it is small
1135        enough not to be a problem. It makes the returned offset consistent with
1136        pcre_exec() and pcre_dfa_exec().
1137    
1138    7.  pcretest now gives a text phrase as well as the error number when
1139        pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
1140        failure, the offset and reason code are output.
1141    
1142    8.  When \R was used with a maximizing quantifier it failed to skip backwards
1143        over a \r\n pair if the subsequent match failed. Instead, it just skipped
1144        back over a single character (\n). This seems wrong (because it treated the
1145        two characters as a single entity when going forwards), conflicts with the
1146        documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
1147        behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
1148        has been changed.
1149    
1150    9.  Some internal refactoring has changed the processing so that the handling
1151        of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
1152        time (the PCRE_DOTALL option was changed this way some time ago: version
1153        7.7 change 16). This has made it possible to abolish the OP_OPT op code,
1154        which was always a bit of a fudge. It also means that there is one less
1155        argument for the match() function, which reduces its stack requirements
1156        slightly. This change also fixes an incompatibility with Perl: the pattern
1157        (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
1158    
1159    10. More internal refactoring has drastically reduced the number of recursive
1160        calls to match() for possessively repeated groups such as (abc)++ when
1161        using pcre_exec().
1162    
1163    11. While implementing 10, a number of bugs in the handling of groups were
1164        discovered and fixed:
1165    
1166        (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
1167        (a|)*(?1) gave a compile-time internal error.
1168        ((a|)+)+  did not notice that the outer group could match an empty string.
1169        (^a|^)+   was not marked as anchored.
1170        (.*a|.*)+ was not marked as matching at start or after a newline.
1171    
1172    12. Yet more internal refactoring has removed another argument from the match()
1173        function. Special calls to this function are now indicated by setting a
1174        value in a variable in the "match data" data block.
1175    
1176    13. Be more explicit in pcre_study() instead of relying on "default" for
1177        opcodes that mean there is no starting character; this means that when new
1178        ones are added and accidentally left out of pcre_study(), testing should
1179        pick them up.
1180    
1181    14. The -s option of pcretest has been documented for ages as being an old
1182        synonym of -m (show memory usage). I have changed it to mean "force study
1183        for every regex", that is, assume /S for every regex. This is similar to -i
1184        and -d etc. It's slightly incompatible, but I'm hoping nobody is still
1185        using it. It makes it easier to run collections of tests with and without
1186        study enabled, and thereby test pcre_study() more easily. All the standard
1187        tests are now run with and without -s (but some patterns can be marked as
1188        "never study" - see 20 below).
1189    
1190    15. When (*ACCEPT) was used in a subpattern that was called recursively, the
1191        restoration of the capturing data to the outer values was not happening
1192        correctly.
1193    
1194    16. If a recursively called subpattern ended with (*ACCEPT) and matched an
1195        empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
1196        pattern had matched an empty string, and so incorrectly returned a no
1197        match.
1198    
1199    17. There was optimizing code for the last branch of non-capturing parentheses,
1200        and also for the obeyed branch of a conditional subexpression, which used
1201        tail recursion to cut down on stack usage. Unfortunately, now that there is
1202        the possibility of (*THEN) occurring in these branches, tail recursion is
1203        no longer possible because the return has to be checked for (*THEN). These
1204        two optimizations have therefore been removed. [But see 8.20/11 above.]
1205    
1206    18. If a pattern containing \R was studied, it was assumed that \R always
1207        matched two bytes, thus causing the minimum subject length to be
1208        incorrectly computed because \R can also match just one byte.
1209    
1210    19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
1211        was incorrectly computed.
1212    
1213    20. If /S is present twice on a test pattern in pcretest input, it now
1214        *disables* studying, thereby overriding the use of -s on the command line
1215        (see 14 above). This is necessary for one or two tests to keep the output
1216        identical in both cases.
1217    
1218    21. When (*ACCEPT) was used in an assertion that matched an empty string and
1219        PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
1220    
1221    22. When an atomic group that contained a capturing parenthesis was
1222        successfully matched, but the branch in which it appeared failed, the
1223        capturing was not being forgotten if a higher numbered group was later
1224        captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
1225        group 1 to "a", when in fact it should be unset. This applied to multi-
1226        branched capturing and non-capturing groups, repeated or not, and also to
1227        positive assertions (capturing in negative assertions does not happen
1228        in PCRE) and also to nested atomic groups.
1229    
1230    23. Add the ++ qualifier feature to pcretest, to show the remainder of the
1231        subject after a captured substring, to make it easier to tell which of a
1232        number of identical substrings has been captured.
1233    
1234    24. The way atomic groups are processed by pcre_exec() has been changed so that
1235        if they are repeated, backtracking one repetition now resets captured
1236        values correctly. For example, if ((?>(a+)b)+aabab) is matched against
1237        "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
1238        "aaa". Previously, it would have been "a". As part of this code
1239        refactoring, the way recursive calls are handled has also been changed.
1240    
1241    25. If an assertion condition captured any substrings, they were not passed
1242        back unless some other capturing happened later. For example, if
1243        (?(?=(a))a) was matched against "a", no capturing was returned.
1244    
1245    26. When studying a pattern that contained subroutine calls or assertions,
1246        the code for finding the minimum length of a possible match was handling
1247        direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
1248        group 1 called group 2 while simultaneously a separate group 2 called group
1249        1). A stack overflow occurred in this case. I have fixed this by limiting
1250        the recursion depth to 10.
1251    
1252    27. Updated RunTest.bat in the distribution to the version supplied by Tom
1253        Fortmann. This supports explicit test numbers on the command line, and has
1254        argument validation and error reporting.
1255    
1256    28. An instance of \X with an unlimited repeat could fail if at any point the
1257        first character it looked at was a mark character.
1258    
1259    29. Some minor code refactoring concerning Unicode properties and scripts
1260        should reduce the stack requirement of match() slightly.
1261    
1262    30. Added the '=' option to pcretest to check the setting of unused capturing
1263        slots at the end of the pattern, which are documented as being -1, but are
1264        not included in the return count.
1265    
1266    31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
1267        compiled something random. Now it gives a compile-time error (as does
1268        Perl).
1269    
1270    32. A *MARK encountered during the processing of a positive assertion is now
1271        recorded and passed back (compatible with Perl).
1272    
1273    33. If --only-matching or --colour was set on a pcregrep call whose pattern
1274        had alternative anchored branches, the search for a second match in a line
1275        was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
1276        matched the line "0102" twice. The same bug affected patterns that started
1277        with a backwards assertion. For example /\b01|\b02/ also matched "0102"
1278        twice.
1279    
1280    34. Previously, PCRE did not allow quantification of assertions. However, Perl
1281        does, and because of capturing effects, quantifying parenthesized
1282        assertions may at times be useful. Quantifiers are now allowed for
1283        parenthesized assertions.
1284    
1285    35. A minor code tidy in pcre_compile() when checking options for \R usage.
1286    
1287    36. \g was being checked for fancy things in a character class, when it should
1288        just be a literal "g".
1289    
1290    37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
1291        appearance of a nested POSIX class supersedes an apparent external class.
1292        For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
1293        unescaped square brackets may also appear as part of class names. For
1294        example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
1295        more like Perl. (But see 8.20/1 above.)
1296    
1297    38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
1298        was because it thought it was \N{name}, which is not supported).
1299    
1300    39. Add minix to OS list not supporting the -S option in pcretest.
1301    
1302    40. PCRE tries to detect cases of infinite recursion at compile time, but it
1303        cannot analyze patterns in sufficient detail to catch mutual recursions
1304        such as ((?1))((?2)). There is now a runtime test that gives an error if a
1305        subgroup is called recursively as a subpattern for a second time at the
1306        same position in the subject string. In previous releases this might have
1307        been caught by the recursion limit, or it might have run out of stack.
1308    
1309    41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
1310        happen only once. PCRE was, however incorrectly giving a compile time error
1311        "recursive call could loop indefinitely" because it cannot analyze the
1312        pattern in sufficient detail. The compile time test no longer happens when
1313        PCRE is compiling a conditional subpattern, but actual runaway loops are
1314        now caught at runtime (see 40 above).
1315    
1316    42. It seems that Perl allows any characters other than a closing parenthesis
1317        to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
1318        has been changed to be the same.
1319    
1320    43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
1321        as not to get warnings when autogen.sh is called. Also changed
1322        AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
1323    
1324    44. To help people who use pcregrep to scan files containing exceedingly long
1325        lines, the following changes have been made:
1326    
1327        (a) The default value of the buffer size parameter has been increased from
1328            8K to 20K. (The actual buffer used is three times this size.)
1329    
1330        (b) The default can be changed by ./configure --with-pcregrep-bufsize when
1331            PCRE is built.
1332    
1333        (c) A --buffer-size=n option has been added to pcregrep, to allow the size
1334            to be set at run time.
1335    
1336        (d) Numerical values in pcregrep options can be followed by K or M, for
1337            example --buffer-size=50K.
1338    
1339        (e) If a line being scanned overflows pcregrep's buffer, an error is now
1340            given and the return code is set to 2.
1341    
1342    45. Add a pointer to the latest mark to the callout data block.
1343    
1344    46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
1345        partial match of an empty string instead of no match. This was specific to
1346        the use of ".".
1347    
1348    47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
1349        complete match instead of a partial match. This bug was dependent on both
1350        the PCRE_UTF8 and PCRE_DOTALL options being set.
1351    
1352    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
1353        starting byte set, because \b was not being ignored.
1354    
1355    
1356    Version 8.12 15-Jan-2011
1357    ------------------------
1358    
1359    1.  Fixed some typos in the markup of the man pages, and wrote a script that
1360        checks for such things as part of the documentation building process.
1361    
1362    2.  On a big-endian 64-bit system, pcregrep did not correctly process the
1363        --match-limit and --recursion-limit options (added for 8.11). In
1364        particular, this made one of the standard tests fail. (The integer value
1365        went into the wrong half of a long int.)
1366    
1367    3.  If the --colour option was given to pcregrep with -v (invert match), it
1368        did strange things, either producing crazy output, or crashing. It should,
1369        of course, ignore a request for colour when reporting lines that do not
1370        match.
1371    
1372    4.  Another pcregrep bug caused similar problems if --colour was specified with
1373        -M (multiline) and the pattern match finished with a line ending.
1374    
1375    5.  In pcregrep, when a pattern that ended with a literal newline sequence was
1376        matched in multiline mode, the following line was shown as part of the
1377        match. This seems wrong, so I have changed it.
1378    
1379    6.  Another pcregrep bug in multiline mode, when --colour was specified, caused
1380        the check for further matches in the same line (so they could be coloured)
1381        to overrun the end of the current line. If another match was found, it was
1382        incorrectly shown (and then shown again when found in the next line).
1383    
1384    7.  If pcregrep was compiled under Windows, there was a reference to the
1385        function pcregrep_exit() before it was defined. I am assuming this was
1386        the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
1387        reported by a user. I've moved the definition above the reference.
1388    
1389    
1390    Version 8.11 10-Dec-2010
1391    ------------------------
1392    
1393    1.  (*THEN) was not working properly if there were untried alternatives prior
1394        to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
1395        backtracked to try for "b" instead of moving to the next alternative branch
1396        at the same level (in this case, to look for "c"). The Perl documentation
1397        is clear that when (*THEN) is backtracked onto, it goes to the "next
1398        alternative in the innermost enclosing group".
1399    
1400    2.  (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
1401        such as   (A(*COMMIT)B(*THEN)C|D)  any failure after matching A should
1402        result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
1403        (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
1404        (*THEN).
1405    
1406    3.  If \s appeared in a character class, it removed the VT character from
1407        the class, even if it had been included by some previous item, for example
1408        in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
1409        of \s, but is part of the POSIX "space" class.)
1410    
1411    4.  A partial match never returns an empty string (because you can always
1412        match an empty string at the end of the subject); however the checking for
1413        an empty string was starting at the "start of match" point. This has been
1414        changed to the "earliest inspected character" point, because the returned
1415        data for a partial match starts at this character. This means that, for
1416        example, /(?<=abc)def/ gives a partial match for the subject "abc"
1417        (previously it gave "no match").
1418    
1419    5.  Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
1420        of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
1421        previously a full match would be given. However, setting PCRE_PARTIAL_HARD
1422        has an implication that the given string is incomplete (because a partial
1423        match is preferred over a full match). For this reason, these items now
1424        give a partial match in this situation. [Aside: previously, the one case
1425        /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
1426        match rather than a full match, which was wrong by the old rules, but is
1427        now correct.]
1428    
1429    6.  There was a bug in the handling of #-introduced comments, recognized when
1430        PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
1431        If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
1432        UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
1433        scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
1434        but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
1435        places in pcre_compile().
1436    
1437    7.  Related to (6) above, when pcre_compile() was skipping #-introduced
1438        comments when looking ahead for named forward references to subpatterns,
1439        the only newline sequence it recognized was NL. It now handles newlines
1440        according to the set newline convention.
1441    
1442    8.  SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
1443        former, but used strtoul(), whereas pcretest avoided strtoul() but did not
1444        cater for a lack of strerror(). These oversights have been fixed.
1445    
1446    9.  Added --match-limit and --recursion-limit to pcregrep.
1447    
1448    10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
1449    
1450    11. When the -o option was used, pcregrep was setting a return code of 1, even
1451        when matches were found, and --line-buffered was not being honoured.
1452    
1453    12. Added an optional parentheses number to the -o and --only-matching options
1454        of pcregrep.
1455    
1456    13. Imitating Perl's /g action for multiple matches is tricky when the pattern
1457        can match an empty string. The code to do it in pcretest and pcredemo
1458        needed fixing:
1459    
1460        (a) When the newline convention was "crlf", pcretest got it wrong, skipping
1461            only one byte after an empty string match just before CRLF (this case
1462            just got forgotten; "any" and "anycrlf" were OK).
1463    
1464        (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
1465            mode when an empty string match preceded an ASCII character followed by
1466            a non-ASCII character. (The code for advancing by one character rather
1467            than one byte was nonsense.)
1468    
1469        (c) The pcredemo.c sample program did not have any code at all to handle
1470            the cases when CRLF is a valid newline sequence.
1471    
1472    14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
1473        as a starting offset was within the subject string. There is now a new
1474        error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
1475        negative or greater than the length of the string. In order to test this,
1476        pcretest is extended to allow the setting of negative starting offsets.
1477    
1478    15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
1479        starting offset points to the beginning of a UTF-8 character was
1480        unnecessarily clumsy. I tidied it up.
1481    
1482    16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
1483        bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
1484    
1485    17. Nobody had reported that the --include_dir option, which was added in
1486        release 7.7 should have been called --include-dir (hyphen, not underscore)
1487        for compatibility with GNU grep. I have changed it to --include-dir, but
1488        left --include_dir as an undocumented synonym, and the same for
1489        --exclude-dir, though that is not available in GNU grep, at least as of
1490        release 2.5.4.
1491    
1492    18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
1493        characters from a string of bytes) have been redefined so as not to use
1494        loops, in order to improve performance in some environments. At the same
1495        time, I abstracted some of the common code into auxiliary macros to save
1496        repetition (this should not affect the compiled code).
1497    
1498    19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
1499        compile-time error is now given if \c is not followed by an ASCII
1500        character, that is, a byte less than 128. (In EBCDIC mode, the code is
1501        different, and any byte value is allowed.)
1502    
1503    20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
1504        START_OPTIMIZE option, which is now allowed at compile time - but just
1505        passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
1506        to pcregrep and other applications that have no direct access to PCRE
1507        options. The new /Y option in pcretest sets this option when calling
1508        pcre_compile().
1509    
1510    21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
1511        back references. Groups containing recursive back references were forced to
1512        be atomic by that change, but in the case of named groups, the amount of
1513        memory required was incorrectly computed, leading to "Failed: internal
1514        error: code overflow". This has been fixed.
1515    
1516    22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
1517        pcretest.c, to avoid build problems in some Borland environments.
1518    
1519    
1520    Version 8.10 25-Jun-2010
1521    ------------------------
1522    
1523    1.  Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
1524        THEN.
1525    
1526    2.  (*ACCEPT) was not working when inside an atomic group.
1527    
1528    3.  Inside a character class, \B is treated as a literal by default, but
1529        faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
1530        causes the error). The code is unchanged, but I tidied the documentation.
1531    
1532    4.  Inside a character class, PCRE always treated \R and \X as literals,
1533        whereas Perl faults them if its -w option is set. I have changed PCRE so
1534        that it faults them when PCRE_EXTRA is set.
1535    
1536    5.  Added support for \N, which always matches any character other than
1537        newline. (It is the same as "." when PCRE_DOTALL is not set.)
1538    
1539    6.  When compiling pcregrep with newer versions of gcc which may have
1540        FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
1541        declared with attribute warn_unused_result" were given. Just casting the
1542        result to (void) does not stop the warnings; a more elaborate fudge is
1543        needed. I've used a macro to implement this.
1544    
1545    7.  Minor change to pcretest.c to avoid a compiler warning.
1546    
1547    8.  Added four artifical Unicode properties to help with an option to make
1548        \s etc use properties (see next item). The new properties are: Xan
1549        (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
1550    
1551    9.  Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
1552        use Unicode properties. (*UCP) at the start of a pattern can be used to set
1553        this option. Modified pcretest to add /W to test this facility. Added
1554        REG_UCP to make it available via the POSIX interface.
1555    
1556    10. Added --line-buffered to pcregrep.
1557    
1558    11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
1559        studied, and the match started with a letter with a code point greater than
1560        127 whose first byte was different to the first byte of the other case of
1561        the letter, the other case of this starting letter was not recognized
1562        (#976).
1563    
1564    12. If a pattern that was studied started with a repeated Unicode property
1565        test, for example, \p{Nd}+, there was the theoretical possibility of
1566        setting up an incorrect bitmap of starting bytes, but fortunately it could
1567        not have actually happened in practice until change 8 above was made (it
1568        added property types that matched character-matching opcodes).
1569    
1570    13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
1571        possible starting bytes for non-anchored patterns.
1572    
1573    14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
1574        \R, and also a number of cases that involve Unicode properties, both
1575        explicit and implicit when PCRE_UCP is set.
1576    
1577    15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
1578        input, it could crash or give wrong results if characters with values
1579        greater than 0xc0 were present in the subject string. (Detail: it assumed
1580        UTF-8 input when processing these items.)
1581    
1582    16. Added a lot of (int) casts to avoid compiler warnings in systems where
1583        size_t is 64-bit (#991).
1584    
1585    17. Added a check for running out of memory when PCRE is compiled with
1586        --disable-stack-for-recursion (#990).
1587    
1588    18. If the last data line in a file for pcretest does not have a newline on
1589        the end, a newline was missing in the output.
1590    
1591    19. The default pcre_chartables.c file recognizes only ASCII characters (values
1592        less than 128) in its various bitmaps. However, there is a facility for
1593        generating tables according to the current locale when PCRE is compiled. It
1594        turns out that in some environments, 0x85 and 0xa0, which are Unicode space
1595        characters, are recognized by isspace() and therefore were getting set in
1596        these tables, and indeed these tables seem to approximate to ISO 8859. This
1597        caused a problem in UTF-8 mode when pcre_study() was used to create a list
1598        of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
1599        which of course cannot start UTF-8 characters. I have changed the code so
1600        that only real ASCII characters (less than 128) and the correct starting
1601        bytes for UTF-8 encodings are set for characters greater than 127 when in
1602        UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
1603        altogether.)
1604    
1605    20. Added the /T option to pcretest so as to be able to run tests with non-
1606        standard character tables, thus making it possible to include the tests
1607        used for 19 above in the standard set of tests.
1608    
1609    21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
1610        reference to a subpattern the other side of a comment that contains an
1611        opening parenthesis caused either an internal compiling error, or a
1612        reference to the wrong subpattern.
1613    
1614    
1615    Version 8.02 19-Mar-2010
1616  ------------------------  ------------------------
1617    
1618  1.  The Unicode data tables have been updated to Unicode 5.2.0.  1.  The Unicode data tables have been updated to Unicode 5.2.0.
1619    
1620    2.  Added the option --libs-cpp to pcre-config, but only when C++ support is
1621        configured.
1622    
1623    3.  Updated the licensing terms in the pcregexp.pas file, as agreed with the
1624        original author of that file, following a query about its status.
1625    
1626    4.  On systems that do not have stdint.h (e.g. Solaris), check for and include
1627        inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
1628    
1629    5.  A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
1630        quantifier applied to a forward-referencing subroutine call, could compile
1631        incorrect code or give the error "internal error: previously-checked
1632        referenced subpattern not found".
1633    
1634    6.  Both MS Visual Studio and Symbian OS have problems with initializing
1635        variables to point to external functions. For these systems, therefore,
1636        pcre_malloc etc. are now initialized to local functions that call the
1637        relevant global functions.
1638    
1639    7.  There were two entries missing in the vectors called coptable and poptable
1640        in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
1641        I've fixed the data, and added a kludgy way of testing at compile time that
1642        the lengths are correct (equal to the number of opcodes).
1643    
1644    8.  Following on from 7, I added a similar kludge to check the length of the
1645        eint vector in pcreposix.c.
1646    
1647    9.  Error texts for pcre_compile() are held as one long string to avoid too
1648        much relocation at load time. To find a text, the string is searched,
1649        counting zeros. There was no check for running off the end of the string,
1650        which could happen if a new error number was added without updating the
1651        string.
1652    
1653    10. \K gave a compile-time error if it appeared in a lookbehind assersion.
1654    
1655    11. \K was not working if it appeared in an atomic group or in a group that
1656        was called as a "subroutine", or in an assertion. Perl 5.11 documents that
1657        \K is "not well defined" if used in an assertion. PCRE now accepts it if
1658        the assertion is positive, but not if it is negative.
1659    
1660    12. Change 11 fortuitously reduced the size of the stack frame used in the
1661        "match()" function of pcre_exec.c by one pointer. Forthcoming
1662        implementation of support for (*MARK) will need an extra pointer on the
1663        stack; I have reserved it now, so that the stack frame size does not
1664        decrease.
1665    
1666    13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
1667        item in branch that calls a recursion is a subroutine call - as in the
1668        second branch in the above example - was incorrectly given the compile-
1669        time error "recursive call could loop indefinitely" because pcre_compile()
1670        was not correctly checking the subroutine for matching a non-empty string.
1671    
1672    14. The checks for overrunning compiling workspace could trigger after an
1673        overrun had occurred. This is a "should never occur" error, but it can be
1674        triggered by pathological patterns such as hundreds of nested parentheses.
1675        The checks now trigger 100 bytes before the end of the workspace.
1676    
1677    15. Fix typo in configure.ac: "srtoq" should be "strtoq".
1678    
1679    
1680  Version 8.01 19-Jan-2010  Version 8.01 19-Jan-2010
1681  ------------------------  ------------------------
# Line 333  Version 7.9 11-Apr-09 Line 2003  Version 7.9 11-Apr-09
2003  7.  A pattern that could match an empty string could cause pcregrep to loop; it  7.  A pattern that could match an empty string could cause pcregrep to loop; it
2004      doesn't make sense to accept an empty string match in pcregrep, so I have      doesn't make sense to accept an empty string match in pcregrep, so I have
2005      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
2006      seems to be how GNU grep behaves.      seems to be how GNU grep behaves. [But see later change 40 for release
2007        8.33.]
2008    
2009  8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at  8.  The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
2010      start or after a newline", because the conditional assertion was not being      start or after a newline", because the conditional assertion was not being
# Line 576  Version 7.7 07-May-08 Line 2247  Version 7.7 07-May-08
2247      containing () gave an internal compiling error instead of "reference to      containing () gave an internal compiling error instead of "reference to
2248      non-existent subpattern". Fortunately, when the pattern did exist, the      non-existent subpattern". Fortunately, when the pattern did exist, the
2249      compiled code was correct. (When scanning forwards to check for the      compiled code was correct. (When scanning forwards to check for the
2250      existencd of the subpattern, it was treating the data ']' as terminating      existence of the subpattern, it was treating the data ']' as terminating
2251      the class, so got the count wrong. When actually compiling, the reference      the class, so got the count wrong. When actually compiling, the reference
2252      was subsequently set up correctly.)      was subsequently set up correctly.)
2253    

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