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

Diff of /code/trunk/ChangeLog

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

revision 989 by zherczeg, Sat Jul 7 11:11:02 2012 UTC revision 1596 by zherczeg, Wed Aug 26 13:44:24 2015 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.32  Note that the PCRE 8.xx series (PCRE1) is now in a bugfix-only state. All
5  ------------  development is happening in the PCRE2 10.xx series.
6    
7    Version 8.38 xx-xxx-xxxx
8    ------------------------
9    
10    1.  If a group that contained a recursive back reference also contained a
11        forward reference subroutine call followed by a non-forward-reference
12        subroutine call, for example /.((?2)(?R)\1)()/, pcre2_compile() failed to
13        compile correct code, leading to undefined behaviour or an internally
14        detected error. This bug was discovered by the LLVM fuzzer.
15    
16    2.  Quantification of certain items (e.g. atomic back references) could cause
17        incorrect code to be compiled when recursive forward references were
18        involved. For example, in this pattern: /(?1)()((((((\1++))\x85)+)|))/.
19        This bug was discovered by the LLVM fuzzer.
20    
21    3.  A repeated conditional group whose condition was a reference by name caused
22        a buffer overflow if there was more than one group with the given name.
23        This bug was discovered by the LLVM fuzzer.
24    
25    4.  A recursive back reference by name within a group that had the same name as
26        another group caused a buffer overflow. For example:
27        /(?J)(?'d'(?'d'\g{d}))/. This bug was discovered by the LLVM fuzzer.
28    
29    5.  A forward reference by name to a group whose number is the same as the
30        current group, for example in this pattern: /(?|(\k'Pm')|(?'Pm'))/, caused
31        a buffer overflow at compile time. This bug was discovered by the LLVM
32        fuzzer.
33    
34    6.  A lookbehind assertion within a set of mutually recursive subpatterns could
35        provoke a buffer overflow. This bug was discovered by the LLVM fuzzer.
36    
37    7.  Another buffer overflow bug involved duplicate named groups with a
38        reference between their definition, with a group that reset capture
39        numbers, for example: /(?J:(?|(?'R')(\k'R')|((?'R'))))/. This has been
40        fixed by always allowing for more memory, even if not needed. (A proper fix
41        is implemented in PCRE2, but it involves more refactoring.)
42    
43    8.  There was no check for integer overflow in subroutine calls such as (?123).
44    
45    9.  The table entry for \l in EBCDIC environments was incorrect, leading to its
46        being treated as a literal 'l' instead of causing an error.
47    
48    10. There was a buffer overflow if pcre_exec() was called with an ovector of
49        size 1. This bug was found by american fuzzy lop.
50    
51    11. If a non-capturing group containing a conditional group that could match
52        an empty string was repeated, it was not identified as matching an empty
53        string itself. For example: /^(?:(?(1)x|)+)+$()/.
54    
55    12. In an EBCDIC environment, pcretest was mishandling the escape sequences
56        \a and \e in test subject lines.
57    
58    13. In an EBCDIC environment, \a in a pattern was converted to the ASCII
59        instead of the EBCDIC value.
60    
61    14. The handling of \c in an EBCDIC environment has been revised so that it is
62        now compatible with the specification in Perl's perlebcdic page.
63    
64    15. The EBCDIC character 0x41 is a non-breaking space, equivalent to 0xa0 in
65        ASCII/Unicode. This has now been added to the list of characters that are
66        recognized as white space in EBCDIC.
67    
68    16. When PCRE was compiled without UCP support, the use of \p and \P gave an
69        error (correctly) when used outside a class, but did not give an error
70        within a class.
71    
72    17. \h within a class was incorrectly compiled in EBCDIC environments.
73    
74    18. A pattern with an unmatched closing parenthesis that contained a backward
75        assertion which itself contained a forward reference caused buffer
76        overflow. And example pattern is: /(?=di(?<=(?1))|(?=(.))))/.
77    
78    19. JIT should return with error when the compiled pattern requires more stack
79        space than the maximum.
80    
81    20. A possessively repeated conditional group that could match an empty string,
82        for example, /(?(R))*+/, was incorrectly compiled.
83    
84    21. Fix infinite recursion in the JIT compiler when certain patterns such as
85        /(?:|a|){100}x/ are analysed.
86    
87    22. Some patterns with character classes involving [: and \\ were incorrectly
88        compiled and could cause reading from uninitialized memory or an incorrect
89        error diagnosis.
90    
91    23. Pathological patterns containing many nested occurrences of [: caused
92        pcre_compile() to run for a very long time.
93    
94    24. A conditional group with only one branch has an implicit empty alternative
95        branch and must therefore be treated as potentially matching an empty
96        string.
97    
98    25. If (?R was followed by - or + incorrect behaviour happened instead of a
99        diagnostic.
100    
101    26. Arrange to give up on finding the minimum matching length for overly
102        complex patterns.
103    
104    27. Similar to (4) above: in a pattern with duplicated named groups and an
105        occurrence of (?| it is possible for an apparently non-recursive back
106        reference to become recursive if a later named group with the relevant
107        number is encountered. This could lead to a buffer overflow. Wen Guanxing
108        from Venustech ADLAB discovered this bug.
109    
110    28. If pcregrep was given the -q option with -c or -l, or when handling a
111        binary file, it incorrectly wrote output to stdout.
112    
113    29. The JIT compiler did not restore the control verb head in case of *THEN
114        control verbs. This issue was found by Karl Skomski with a custom LLVM
115        fuzzer.
116    
117    30. Error messages for syntax errors following \g and \k were giving inaccurate
118        offsets in the pattern.
119    
120    31. Added a check for integer overflow in conditions (?(<digits>) and
121        (?(R<digits>). This omission was discovered by Karl Skomski with the LLVM
122        fuzzer.
123    
124    32. Handling recursive references such as (?2) when the reference is to a group
125        later in the pattern uses code that is very hacked about and error-prone.
126        It has been re-written for PCRE2. Here in PCRE1, a check has been added to
127        give an internal error if it is obvious that compiling has gone wrong.
128    
129    33. The JIT compiler should not check repeats after a {0,1} repeat byte code.
130        This issue was found by Karl Skomski with a custom LLVM fuzzer.
131    
132    34. The JIT compiler should restore the control chain for empty possessive
133        repeats. This issue was found by Karl Skomski with a custom LLVM fuzzer.
134    
135    35. Match limit check added to JIT recursion. This issue was found by Karl
136        Skomski with a custom LLVM fuzzer.
137    
138    36. Yet another case similar to 27 above has been circumvented by an
139        unconditional allocation of extra memory. This issue is fixed "properly" in
140        PCRE2 by refactoring the way references are handled. Wen Guanxing
141        from Venustech ADLAB discovered this bug.
142    
143    37. Fix two assertion fails in JIT. These issues were found by Karl Skomski
144        with a custom LLVM fuzzer.
145    
146    38. Fixed a corner case of range optimization in JIT.
147    
148    
149    Version 8.37 28-April-2015
150    --------------------------
151    
152    1.  When an (*ACCEPT) is triggered inside capturing parentheses, it arranges
153        for those parentheses to be closed with whatever has been captured so far.
154        However, it was failing to mark any other groups between the hightest
155        capture so far and the currrent group as "unset". Thus, the ovector for
156        those groups contained whatever was previously there. An example is the
157        pattern /(x)|((*ACCEPT))/ when matched against "abcd".
158    
159    2.  If an assertion condition was quantified with a minimum of zero (an odd
160        thing to do, but it happened), SIGSEGV or other misbehaviour could occur.
161    
162    3.  If a pattern in pcretest input had the P (POSIX) modifier followed by an
163        unrecognized modifier, a crash could occur.
164    
165    4.  An attempt to do global matching in pcretest with a zero-length ovector
166        caused a crash.
167    
168    5.  Fixed a memory leak during matching that could occur for a subpattern
169        subroutine call (recursive or otherwise) if the number of captured groups
170        that had to be saved was greater than ten.
171    
172    6.  Catch a bad opcode during auto-possessification after compiling a bad UTF
173        string with NO_UTF_CHECK. This is a tidyup, not a bug fix, as passing bad
174        UTF with NO_UTF_CHECK is documented as having an undefined outcome.
175    
176    7.  A UTF pattern containing a "not" match of a non-ASCII character and a
177        subroutine reference could loop at compile time. Example: /[^\xff]((?1))/.
178    
179    8. When a pattern is compiled, it remembers the highest back reference so that
180       when matching, if the ovector is too small, extra memory can be obtained to
181       use instead. A conditional subpattern whose condition is a check on a
182       capture having happened, such as, for example in the pattern
183       /^(?:(a)|b)(?(1)A|B)/, is another kind of back reference, but it was not
184       setting the highest backreference number. This mattered only if pcre_exec()
185       was called with an ovector that was too small to hold the capture, and there
186       was no other kind of back reference (a situation which is probably quite
187       rare). The effect of the bug was that the condition was always treated as
188       FALSE when the capture could not be consulted, leading to a incorrect
189       behaviour by pcre_exec(). This bug has been fixed.
190    
191    9. A reference to a duplicated named group (either a back reference or a test
192       for being set in a conditional) that occurred in a part of the pattern where
193       PCRE_DUPNAMES was not set caused the amount of memory needed for the pattern
194       to be incorrectly calculated, leading to overwriting.
195    
196    10. A mutually recursive set of back references such as (\2)(\1) caused a
197        segfault at study time (while trying to find the minimum matching length).
198        The infinite loop is now broken (with the minimum length unset, that is,
199        zero).
200    
201    11. If an assertion that was used as a condition was quantified with a minimum
202        of zero, matching went wrong. In particular, if the whole group had
203        unlimited repetition and could match an empty string, a segfault was
204        likely. The pattern (?(?=0)?)+ is an example that caused this. Perl allows
205        assertions to be quantified, but not if they are being used as conditions,
206        so the above pattern is faulted by Perl. PCRE has now been changed so that
207        it also rejects such patterns.
208    
209    12. A possessive capturing group such as (a)*+ with a minimum repeat of zero
210        failed to allow the zero-repeat case if pcre2_exec() was called with an
211        ovector too small to capture the group.
212    
213    13. Fixed two bugs in pcretest that were discovered by fuzzing and reported by
214        Red Hat Product Security:
215    
216        (a) A crash if /K and /F were both set with the option to save the compiled
217        pattern.
218    
219        (b) Another crash if the option to print captured substrings in a callout
220        was combined with setting a null ovector, for example \O\C+ as a subject
221        string.
222    
223    14. A pattern such as "((?2){0,1999}())?", which has a group containing a
224        forward reference repeated a large (but limited) number of times within a
225        repeated outer group that has a zero minimum quantifier, caused incorrect
226        code to be compiled, leading to the error "internal error:
227        previously-checked referenced subpattern not found" when an incorrect
228        memory address was read. This bug was reported as "heap overflow",
229        discovered by Kai Lu of Fortinet's FortiGuard Labs and given the CVE number
230        CVE-2015-2325.
231    
232    23. A pattern such as "((?+1)(\1))/" containing a forward reference subroutine
233        call within a group that also contained a recursive back reference caused
234        incorrect code to be compiled. This bug was reported as "heap overflow",
235        discovered by Kai Lu of Fortinet's FortiGuard Labs, and given the CVE
236        number CVE-2015-2326.
237    
238    24. Computing the size of the JIT read-only data in advance has been a source
239        of various issues, and new ones are still appear unfortunately. To fix
240        existing and future issues, size computation is eliminated from the code,
241        and replaced by on-demand memory allocation.
242    
243    25. A pattern such as /(?i)[A-`]/, where characters in the other case are
244        adjacent to the end of the range, and the range contained characters with
245        more than one other case, caused incorrect behaviour when compiled in UTF
246        mode. In that example, the range a-j was left out of the class.
247    
248    26. Fix JIT compilation of conditional blocks, which assertion
249        is converted to (*FAIL). E.g: /(?(?!))/.
250    
251    27. The pattern /(?(?!)^)/ caused references to random memory. This bug was
252        discovered by the LLVM fuzzer.
253    
254    28. The assertion (?!) is optimized to (*FAIL). This was not handled correctly
255        when this assertion was used as a condition, for example (?(?!)a|b). In
256        pcre2_match() it worked by luck; in pcre2_dfa_match() it gave an incorrect
257        error about an unsupported item.
258    
259    29. For some types of pattern, for example /Z*(|d*){216}/, the auto-
260        possessification code could take exponential time to complete. A recursion
261        depth limit of 1000 has been imposed to limit the resources used by this
262        optimization.
263    
264    30. A pattern such as /(*UTF)[\S\V\H]/, which contains a negated special class
265        such as \S in non-UCP mode, explicit wide characters (> 255) can be ignored
266        because \S ensures they are all in the class. The code for doing this was
267        interacting badly with the code for computing the amount of space needed to
268        compile the pattern, leading to a buffer overflow. This bug was discovered
269        by the LLVM fuzzer.
270    
271    31. A pattern such as /((?2)+)((?1))/ which has mutual recursion nested inside
272        other kinds of group caused stack overflow at compile time. This bug was
273        discovered by the LLVM fuzzer.
274    
275    32. A pattern such as /(?1)(?#?'){8}(a)/ which had a parenthesized comment
276        between a subroutine call and its quantifier was incorrectly compiled,
277        leading to buffer overflow or other errors. This bug was discovered by the
278        LLVM fuzzer.
279    
280    33. The illegal pattern /(?(?<E>.*!.*)?)/ was not being diagnosed as missing an
281        assertion after (?(. The code was failing to check the character after
282        (?(?< for the ! or = that would indicate a lookbehind assertion. This bug
283        was discovered by the LLVM fuzzer.
284    
285    34. A pattern such as /X((?2)()*+){2}+/ which has a possessive quantifier with
286        a fixed maximum following a group that contains a subroutine reference was
287        incorrectly compiled and could trigger buffer overflow. This bug was
288        discovered by the LLVM fuzzer.
289    
290    35. A mutual recursion within a lookbehind assertion such as (?<=((?2))((?1)))
291        caused a stack overflow instead of the diagnosis of a non-fixed length
292        lookbehind assertion. This bug was discovered by the LLVM fuzzer.
293    
294    36. The use of \K in a positive lookbehind assertion in a non-anchored pattern
295        (e.g. /(?<=\Ka)/) could make pcregrep loop.
296    
297    37. There was a similar problem to 36 in pcretest for global matches.
298    
299    38. If a greedy quantified \X was preceded by \C in UTF mode (e.g. \C\X*),
300        and a subsequent item in the pattern caused a non-match, backtracking over
301        the repeated \X did not stop, but carried on past the start of the subject,
302        causing reference to random memory and/or a segfault. There were also some
303        other cases where backtracking after \C could crash. This set of bugs was
304        discovered by the LLVM fuzzer.
305    
306    39. The function for finding the minimum length of a matching string could take
307        a very long time if mutual recursion was present many times in a pattern,
308        for example, /((?2){73}(?2))((?1))/. A better mutual recursion detection
309        method has been implemented. This infelicity was discovered by the LLVM
310        fuzzer.
311    
312    40. Static linking against the PCRE library using the pkg-config module was
313        failing on missing pthread symbols.
314    
315    
316    Version 8.36 26-September-2014
317    ------------------------------
318    
319    1.  Got rid of some compiler warnings in the C++ modules that were shown up by
320        -Wmissing-field-initializers and -Wunused-parameter.
321    
322    2.  The tests for quantifiers being too big (greater than 65535) were being
323        applied after reading the number, and stupidly assuming that integer
324        overflow would give a negative number. The tests are now applied as the
325        numbers are read.
326    
327    3.  Tidy code in pcre_exec.c where two branches that used to be different are
328        now the same.
329    
330    4.  The JIT compiler did not generate match limit checks for certain
331        bracketed expressions with quantifiers. This may lead to exponential
332        backtracking, instead of returning with PCRE_ERROR_MATCHLIMIT. This
333        issue should be resolved now.
334    
335    5.  Fixed an issue, which occures when nested alternatives are optimized
336        with table jumps.
337    
338    6.  Inserted two casts and changed some ints to size_t in the light of some
339        reported 64-bit compiler warnings (Bugzilla 1477).
340    
341    7.  Fixed a bug concerned with zero-minimum possessive groups that could match
342        an empty string, which sometimes were behaving incorrectly in the
343        interpreter (though correctly in the JIT matcher). This pcretest input is
344        an example:
345    
346          '\A(?:[^"]++|"(?:[^"]*+|"")*+")++'
347          NON QUOTED "QUOT""ED" AFTER "NOT MATCHED
348    
349        the interpreter was reporting a match of 'NON QUOTED ' only, whereas the
350        JIT matcher and Perl both matched 'NON QUOTED "QUOT""ED" AFTER '. The test
351        for an empty string was breaking the inner loop and carrying on at a lower
352        level, when possessive repeated groups should always return to a higher
353        level as they have no backtrack points in them. The empty string test now
354        occurs at the outer level.
355    
356    8.  Fixed a bug that was incorrectly auto-possessifying \w+ in the pattern
357        ^\w+(?>\s*)(?<=\w) which caused it not to match "test test".
358    
359    9.  Give a compile-time error for \o{} (as Perl does) and for \x{} (which Perl
360        doesn't).
361    
362    10. Change 8.34/15 introduced a bug that caused the amount of memory needed
363        to hold a pattern to be incorrectly computed (too small) when there were
364        named back references to duplicated names. This could cause "internal
365        error: code overflow" or "double free or corruption" or other memory
366        handling errors.
367    
368    11. When named subpatterns had the same prefixes, back references could be
369        confused. For example, in this pattern:
370    
371          /(?P<Name>a)?(?P<Name2>b)?(?(<Name>)c|d)*l/
372    
373        the reference to 'Name' was incorrectly treated as a reference to a
374        duplicate name.
375    
376    12. A pattern such as /^s?c/mi8 where the optional character has more than
377        one "other case" was incorrectly compiled such that it would only try to
378        match starting at "c".
379    
380    13. When a pattern starting with \s was studied, VT was not included in the
381        list of possible starting characters; this should have been part of the
382        8.34/18 patch.
383    
384    14. If a character class started [\Qx]... where x is any character, the class
385        was incorrectly terminated at the ].
386    
387    15. If a pattern that started with a caseless match for a character with more
388        than one "other case" was studied, PCRE did not set up the starting code
389        unit bit map for the list of possible characters. Now it does. This is an
390        optimization improvement, not a bug fix.
391    
392    16. The Unicode data tables have been updated to Unicode 7.0.0.
393    
394    17. Fixed a number of memory leaks in pcregrep.
395    
396    18. Avoid a compiler warning (from some compilers) for a function call with
397        a cast that removes "const" from an lvalue by using an intermediate
398        variable (to which the compiler does not object).
399    
400    19. Incorrect code was compiled if a group that contained an internal recursive
401        back reference was optional (had quantifier with a minimum of zero). This
402        example compiled incorrect code: /(((a\2)|(a*)\g<-1>))*/ and other examples
403        caused segmentation faults because of stack overflows at compile time.
404    
405    20. A pattern such as /((?(R)a|(?1)))+/, which contains a recursion within a
406        group that is quantified with an indefinite repeat, caused a compile-time
407        loop which used up all the system stack and provoked a segmentation fault.
408        This was not the same bug as 19 above.
409    
410    21. Add PCRECPP_EXP_DECL declaration to operator<< in pcre_stringpiece.h.
411        Patch by Mike Frysinger.
412    
413    
414    Version 8.35 04-April-2014
415    --------------------------
416    
417    1.  A new flag is set, when property checks are present in an XCLASS.
418        When this flag is not set, PCRE can perform certain optimizations
419        such as studying these XCLASS-es.
420    
421    2.  The auto-possessification of character sets were improved: a normal
422        and an extended character set can be compared now. Furthermore
423        the JIT compiler optimizes more character set checks.
424    
425    3.  Got rid of some compiler warnings for potentially uninitialized variables
426        that show up only when compiled with -O2.
427    
428    4.  A pattern such as (?=ab\K) that uses \K in an assertion can set the start
429        of a match later then the end of the match. The pcretest program was not
430        handling the case sensibly - it was outputting from the start to the next
431        binary zero. It now reports this situation in a message, and outputs the
432        text from the end to the start.
433    
434    5.  Fast forward search is improved in JIT. Instead of the first three
435        characters, any three characters with fixed position can be searched.
436        Search order: first, last, middle.
437    
438    6.  Improve character range checks in JIT. Characters are read by an inprecise
439        function now, which returns with an unknown value if the character code is
440        above a certain threshold (e.g: 256). The only limitation is that the value
441        must be bigger than the threshold as well. This function is useful when
442        the characters above the threshold are handled in the same way.
443    
444    7.  The macros whose names start with RAWUCHAR are placeholders for a future
445        mode in which only the bottom 21 bits of 32-bit data items are used. To
446        make this more memorable for those maintaining the code, the names have
447        been changed to start with UCHAR21, and an extensive comment has been added
448        to their definition.
449    
450    8.  Add missing (new) files sljitNativeTILEGX.c and sljitNativeTILEGX-encoder.c
451        to the export list in Makefile.am (they were accidentally omitted from the
452        8.34 tarball).
453    
454    9.  The informational output from pcretest used the phrase "starting byte set"
455        which is inappropriate for the 16-bit and 32-bit libraries. As the output
456        for "first char" and "need char" really means "non-UTF-char", I've changed
457        "byte" to "char", and slightly reworded the output. The documentation about
458        these values has also been (I hope) clarified.
459    
460    10. Another JIT related optimization: use table jumps for selecting the correct
461        backtracking path, when more than four alternatives are present inside a
462        bracket.
463    
464    11. Empty match is not possible, when the minimum length is greater than zero,
465        and there is no \K in the pattern. JIT should avoid empty match checks in
466        such cases.
467    
468    12. In a caseless character class with UCP support, when a character with more
469        than one alternative case was not the first character of a range, not all
470        the alternative cases were added to the class. For example, s and \x{17f}
471        are both alternative cases for S: the class [RST] was handled correctly,
472        but [R-T] was not.
473    
474    13. The configure.ac file always checked for pthread support when JIT was
475        enabled. This is not used in Windows, so I have put this test inside a
476        check for the presence of windows.h (which was already tested for).
477    
478    14. Improve pattern prefix search by a simplified Boyer-Moore algorithm in JIT.
479        The algorithm provides a way to skip certain starting offsets, and usually
480        faster than linear prefix searches.
481    
482    15. Change 13 for 8.20 updated RunTest to check for the 'fr' locale as well
483        as for 'fr_FR' and 'french'. For some reason, however, it then used the
484        Windows-specific input and output files, which have 'french' screwed in.
485        So this could never have worked. One of the problems with locales is that
486        they aren't always the same. I have now updated RunTest so that it checks
487        the output of the locale test (test 3) against three different output
488        files, and it allows the test to pass if any one of them matches. With luck
489        this should make the test pass on some versions of Solaris where it was
490        failing. Because of the uncertainty, the script did not used to stop if
491        test 3 failed; it now does. If further versions of a French locale ever
492        come to light, they can now easily be added.
493    
494    16. If --with-pcregrep-bufsize was given a non-integer value such as "50K",
495        there was a message during ./configure, but it did not stop. This now
496        provokes an error. The invalid example in README has been corrected.
497        If a value less than the minimum is given, the minimum value has always
498        been used, but now a warning is given.
499    
500    17. If --enable-bsr-anycrlf was set, the special 16/32-bit test failed. This
501        was a bug in the test system, which is now fixed. Also, the list of various
502        configurations that are tested for each release did not have one with both
503        16/32 bits and --enable-bar-anycrlf. It now does.
504    
505    18. pcretest was missing "-C bsr" for displaying the \R default setting.
506    
507    19. Little endian PowerPC systems are supported now by the JIT compiler.
508    
509    20. The fast forward newline mechanism could enter to an infinite loop on
510        certain invalid UTF-8 input. Although we don't support these cases
511        this issue can be fixed by a performance optimization.
512    
513    21. Change 33 of 8.34 is not sufficient to ensure stack safety because it does
514        not take account if existing stack usage. There is now a new global
515        variable called pcre_stack_guard that can be set to point to an external
516        function to check stack availability. It is called at the start of
517        processing every parenthesized group.
518    
519    22. A typo in the code meant that in ungreedy mode the max/min qualifier
520        behaved like a min-possessive qualifier, and, for example, /a{1,3}b/U did
521        not match "ab".
522    
523    23. When UTF was disabled, the JIT program reported some incorrect compile
524        errors. These messages are silenced now.
525    
526    24. Experimental support for ARM-64 and MIPS-64 has been added to the JIT
527        compiler.
528    
529    25. Change all the temporary files used in RunGrepTest to be different to those
530        used by RunTest so that the tests can be run simultaneously, for example by
531        "make -j check".
532    
533    
534    Version 8.34 15-December-2013
535    -----------------------------
536    
537    1.  Add pcre[16|32]_jit_free_unused_memory to forcibly free unused JIT
538        executable memory. Patch inspired by Carsten Klein.
539    
540    2.  ./configure --enable-coverage defined SUPPORT_GCOV in config.h, although
541        this macro is never tested and has no effect, because the work to support
542        coverage involves only compiling and linking options and special targets in
543        the Makefile. The comment in config.h implied that defining the macro would
544        enable coverage support, which is totally false. There was also support for
545        setting this macro in the CMake files (my fault, I just copied it from
546        configure). SUPPORT_GCOV has now been removed.
547    
548    3.  Make a small performance improvement in strlen16() and strlen32() in
549        pcretest.
550    
551    4.  Change 36 for 8.33 left some unreachable statements in pcre_exec.c,
552        detected by the Solaris compiler (gcc doesn't seem to be able to diagnose
553        these cases). There was also one in pcretest.c.
554    
555    5.  Cleaned up a "may be uninitialized" compiler warning in pcre_exec.c.
556    
557    6.  In UTF mode, the code for checking whether a group could match an empty
558        string (which is used for indefinitely repeated groups to allow for
559        breaking an infinite loop) was broken when the group contained a repeated
560        negated single-character class with a character that occupied more than one
561        data item and had a minimum repetition of zero (for example, [^\x{100}]* in
562        UTF-8 mode). The effect was undefined: the group might or might not be
563        deemed as matching an empty string, or the program might have crashed.
564    
565    7.  The code for checking whether a group could match an empty string was not
566        recognizing that \h, \H, \v, \V, and \R must match a character.
567    
568    8.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
569        an empty string. If it can, pcretest shows this in its information output.
570    
571    9.  Fixed two related bugs that applied to Unicode extended grapheme clusters
572        that were repeated with a maximizing qualifier (e.g. \X* or \X{2,5}) when
573        matched by pcre_exec() without using JIT:
574    
575        (a) If the rest of the pattern did not match after a maximal run of
576            grapheme clusters, the code for backing up to try with fewer of them
577            did not always back up over a full grapheme when characters that do not
578            have the modifier quality were involved, e.g. Hangul syllables.
579    
580        (b) If the match point in a subject started with modifier character, and
581            there was no match, the code could incorrectly back up beyond the match
582            point, and potentially beyond the first character in the subject,
583            leading to a segfault or an incorrect match result.
584    
585    10. A conditional group with an assertion condition could lead to PCRE
586        recording an incorrect first data item for a match if no other first data
587        item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
588        first data item, and therefore matched "ca" after "c" instead of at the
589        start.
590    
591    11. Change 40 for 8.33 (allowing pcregrep to find empty strings) showed up a
592        bug that caused the command "echo a | ./pcregrep -M '|a'" to loop.
593    
594    12. The source of pcregrep now includes z/OS-specific code so that it can be
595        compiled for z/OS as part of the special z/OS distribution.
596    
597    13. Added the -T and -TM options to pcretest.
598    
599    14. The code in pcre_compile.c for creating the table of named capturing groups
600        has been refactored. Instead of creating the table dynamically during the
601        actual compiling pass, the information is remembered during the pre-compile
602        pass (on the stack unless there are more than 20 named groups, in which
603        case malloc() is used) and the whole table is created before the actual
604        compile happens. This has simplified the code (it is now nearly 150 lines
605        shorter) and prepared the way for better handling of references to groups
606        with duplicate names.
607    
608    15. A back reference to a named subpattern when there is more than one of the
609        same name now checks them in the order in which they appear in the pattern.
610        The first one that is set is used for the reference. Previously only the
611        first one was inspected. This change makes PCRE more compatible with Perl.
612    
613    16. Unicode character properties were updated from Unicode 6.3.0.
614    
615    17. The compile-time code for auto-possessification has been refactored, based
616        on a patch by Zoltan Herczeg. It now happens after instead of during
617        compilation. The code is cleaner, and more cases are handled. The option
618        PCRE_NO_AUTO_POSSESS is added for testing purposes, and the -O and /O
619        options in pcretest are provided to set it. It can also be set by
620        (*NO_AUTO_POSSESS) at the start of a pattern.
621    
622    18. The character VT has been added to the default ("C" locale) set of
623        characters that match \s and are generally treated as white space,
624        following this same change in Perl 5.18. There is now no difference between
625        "Perl space" and "POSIX space". Whether VT is treated as white space in
626        other locales depends on the locale.
627    
628    19. The code for checking named groups as conditions, either for being set or
629        for being recursed, has been refactored (this is related to 14 and 15
630        above). Processing unduplicated named groups should now be as fast at
631        numerical groups, and processing duplicated groups should be faster than
632        before.
633    
634    20. Two patches to the CMake build system, by Alexander Barkov:
635    
636          (1) Replace the "source" command by "." in CMakeLists.txt because
637              "source" is a bash-ism.
638    
639          (2) Add missing HAVE_STDINT_H and HAVE_INTTYPES_H to config-cmake.h.in;
640              without these the CMake build does not work on Solaris.
641    
642    21. Perl has changed its handling of \8 and \9. If there is no previously
643        encountered capturing group of those numbers, they are treated as the
644        literal characters 8 and 9 instead of a binary zero followed by the
645        literals. PCRE now does the same.
646    
647    22. Following Perl, added \o{} to specify codepoints in octal, making it
648        possible to specify values greater than 0777 and also making them
649        unambiguous.
650    
651    23. Perl now gives an error for missing closing braces after \x{... instead of
652        treating the string as literal. PCRE now does the same.
653    
654    24. RunTest used to grumble if an inappropriate test was selected explicitly,
655        but just skip it when running all tests. This make it awkward to run ranges
656        of tests when one of them was inappropriate. Now it just skips any
657        inappropriate tests, as it always did when running all tests.
658    
659    25. If PCRE_AUTO_CALLOUT and PCRE_UCP were set for a pattern that contained
660        character types such as \d or \w, too many callouts were inserted, and the
661        data that they returned was rubbish.
662    
663    26. In UCP mode, \s was not matching two of the characters that Perl matches,
664        namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
665        were matched by \h. The code has now been refactored so that the lists of
666        the horizontal and vertical whitespace characters used for \h and \v (which
667        are defined only in one place) are now also used for \s.
668    
669    27. Add JIT support for the 64 bit TileGX architecture.
670        Patch by Jiong Wang (Tilera Corporation).
671    
672    28. Possessive quantifiers for classes (both explicit and automatically
673        generated) now use special opcodes instead of wrapping in ONCE brackets.
674    
675    29. Whereas an item such as A{4}+ ignored the possessivenes of the quantifier
676        (because it's meaningless), this was not happening when PCRE_CASELESS was
677        set. Not wrong, but inefficient.
678    
679    30. Updated perltest.pl to add /u (force Unicode mode) when /W (use Unicode
680        properties for \w, \d, etc) is present in a test regex. Otherwise if the
681        test contains no characters greater than 255, Perl doesn't realise it
682        should be using Unicode semantics.
683    
684    31. Upgraded the handling of the POSIX classes [:graph:], [:print:], and
685        [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
686        does in Unicode mode.
687    
688    32. Added the "forbid" facility to pcretest so that putting tests into the
689        wrong test files can sometimes be quickly detected.
690    
691    33. There is now a limit (default 250) on the depth of nesting of parentheses.
692        This limit is imposed to control the amount of system stack used at compile
693        time. It can be changed at build time by --with-parens-nest-limit=xxx or
694        the equivalent in CMake.
695    
696    34. Character classes such as [A-\d] or [a-[:digit:]] now cause compile-time
697        errors. Perl warns for these when in warning mode, but PCRE has no facility
698        for giving warnings.
699    
700    35. Change 34 for 8.13 allowed quantifiers on assertions, because Perl does.
701        However, this was not working for (?!) because it is optimized to (*FAIL),
702        for which PCRE does not allow quantifiers. The optimization is now disabled
703        when a quantifier follows (?!). I can't see any use for this, but it makes
704        things uniform.
705    
706    36. Perl no longer allows group names to start with digits, so I have made this
707        change also in PCRE. It simplifies the code a bit.
708    
709    37. In extended mode, Perl ignores spaces before a + that indicates a
710        possessive quantifier. PCRE allowed a space before the quantifier, but not
711        before the possessive +. It now does.
712    
713    38. The use of \K (reset reported match start) within a repeated possessive
714        group such as (a\Kb)*+ was not working.
715    
716    40. Document that the same character tables must be used at compile time and
717        run time, and that the facility to pass tables to pcre_exec() and
718        pcre_dfa_exec() is for use only with saved/restored patterns.
719    
720    41. Applied Jeff Trawick's patch CMakeLists.txt, which "provides two new
721        features for Builds with MSVC:
722    
723        1. Support pcre.rc and/or pcreposix.rc (as is already done for MinGW
724           builds). The .rc files can be used to set FileDescription and many other
725           attributes.
726    
727        2. Add an option (-DINSTALL_MSVC_PDB) to enable installation of .pdb files.
728           This allows higher-level build scripts which want .pdb files to avoid
729           hard-coding the exact files needed."
730    
731    42. Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
732        mean "start of word" and "end of word", respectively, as a transition aid.
733    
734    43. A minimizing repeat of a class containing codepoints greater than 255 in
735        non-UTF 16-bit or 32-bit modes caused an internal error when PCRE was
736        compiled to use the heap for recursion.
737    
738    44. Got rid of some compiler warnings for unused variables when UTF but not UCP
739        is configured.
740    
741    
742    Version 8.33 28-May-2013
743    ------------------------
744    
745    1.  Added 'U' to some constants that are compared to unsigned integers, to
746        avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
747        variables that are added to signed variables, to ensure the result is
748        signed and can be negated.
749    
750    2.  Applied patch by Daniel Richard G for quashing MSVC warnings to the
751        CMake config files.
752    
753    3.  Revise the creation of config.h.generic so that all boolean macros are
754        #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
755        overriding via -D on the command line possible.
756    
757    4.  Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
758        to unsigned int is reported to make a quite noticeable speed difference in
759        a specific Windows environment. Testing on Linux did also appear to show
760        some benefit (and it is clearly not harmful). Also fixed the definition of
761        Xop which should be unsigned.
762    
763    5.  Related to (4), changing the definition of the intermediate variable cc
764        in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
765        improvements.
766    
767    6.  Fix forward search in JIT when link size is 3 or greater. Also removed some
768        unnecessary spaces.
769    
770    7.  Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
771        and later.
772    
773    8.  Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
774    
775    9.  Optimizing fast_forward_start_bits in JIT.
776    
777    10. Adding support for callouts in JIT, and fixing some issues revealed
778        during this work. Namely:
779    
780        (a) Unoptimized capturing brackets incorrectly reset on backtrack.
781    
782        (b) Minimum length was not checked before the matching is started.
783    
784    11. The value of capture_last that is passed to callouts was incorrect in some
785        cases when there was a capture on one path that was subsequently abandoned
786        after a backtrack. Also, the capture_last value is now reset after a
787        recursion, since all captures are also reset in this case.
788    
789    12. The interpreter no longer returns the "too many substrings" error in the
790        case when an overflowing capture is in a branch that is subsequently
791        abandoned after a backtrack.
792    
793    13. In the pathological case when an offset vector of size 2 is used, pcretest
794        now prints out the matched string after a yield of 0 or 1.
795    
796    14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
797        Only supported by the JIT compiler at the moment.
798    
799    15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
800    
801    16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
802        offset of the starting point of the matching process, provided the offsets
803        vector is large enough.
804    
805    17. The \A escape now records a lookbehind value of 1, though its execution
806        does not actually inspect the previous character. This is to ensure that,
807        in partial multi-segment matching, at least one character from the old
808        segment is retained when a new segment is processed. Otherwise, if there
809        are no lookbehinds in the pattern, \A might match incorrectly at the start
810        of a new segment.
811    
812    18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
813    
814    19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
815        gives some modest performance improvement in 8-bit mode.
816    
817    20. Added the PCRE-specific property \p{Xuc} for matching characters that can
818        be expressed in certain programming languages using Universal Character
819        Names.
820    
821    21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
822        which points out that "non characters" are not "characters that may not
823        appear in Unicode strings" but rather "characters that are reserved for
824        internal use and have only local meaning".
825    
826    22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
827        there was a conditional group that depended on an assertion, if the
828        assertion was false, the callout that immediately followed the alternation
829        in the condition was skipped when pcre_exec() was used for matching.
830    
831    23. Allow an explicit callout to be inserted before an assertion that is the
832        condition for a conditional group, for compatibility with automatic
833        callouts, which always insert a callout at this point.
834    
835    24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
836        confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
837    
838    25. (*PRUNE) is now supported by the JIT compiler.
839    
840    26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
841    
842    27. Fix the case where there are two or more SKIPs with arguments that may be
843        ignored.
844    
845    28. (*SKIP) is now supported by the JIT compiler.
846    
847    29. (*THEN) is now supported by the JIT compiler.
848    
849    30. Update RunTest with additional test selector options.
850    
851    31. The way PCRE handles backtracking verbs has been changed in two ways.
852    
853        (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
854        SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
855        backtracking. In some cases this makes it more Perl-compatible, but Perl's
856        rather obscure rules do not always do the same thing.
857    
858        (2) Previously, backtracking verbs were confined within assertions. This is
859        no longer the case for positive assertions, except for (*ACCEPT). Again,
860        this sometimes improves Perl compatibility, and sometimes does not.
861    
862    32. A number of tests that were in test 2 because Perl did things differently
863        have been moved to test 1, because either Perl or PCRE has changed, and
864        these tests are now compatible.
865    
866    32. Backtracking control verbs are now handled in the same way in JIT and
867        interpreter.
868    
869    33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
870        contained a forward subroutine reference caused a compile error.
871    
872    34. Auto-detect and optimize limited repetitions in JIT.
873    
874    35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
875        blocking (*UTF) etc.
876    
877    36. In the interpreter, maximizing pattern repetitions for characters and
878        character types now use tail recursion, which reduces stack usage.
879    
880    37. The value of the max lookbehind was not correctly preserved if a compiled
881        and saved regex was reloaded on a host of different endianness.
882    
883    38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
884        of the compiled pattern block, expand the flags field from 16 to 32 bits
885        because it was almost full.
886    
887    39. Try madvise first before posix_madvise.
888    
889    40. Change 7 for PCRE 7.9 made it impossible for pcregrep to find empty lines
890        with a pattern such as ^$. It has taken 4 years for anybody to notice! The
891        original change locked out all matches of empty strings. This has been
892        changed so that one match of an empty string per line is recognized.
893        Subsequent searches on the same line (for colouring or for --only-matching,
894        for example) do not recognize empty strings.
895    
896    41. Applied a user patch to fix a number of spelling mistakes in comments.
897    
898    42. Data lines longer than 65536 caused pcretest to crash.
899    
900    43. Clarified the data type for length and startoffset arguments for pcre_exec
901        and pcre_dfa_exec in the function-specific man pages, where they were
902        explicitly stated to be in bytes, never having been updated. I also added
903        some clarification to the pcreapi man page.
904    
905    44. A call to pcre_dfa_exec() with an output vector size less than 2 caused
906        a segmentation fault.
907    
908    
909    Version 8.32 30-November-2012
910    -----------------------------
911    
912  1.  Improved JIT compiler optimizations for first character search and single  1.  Improved JIT compiler optimizations for first character search and single
913      character iterators.      character iterators.
# Line 12  Version 8.32 Line 917  Version 8.32
917    
918  3.  Single character iterator optimizations in the JIT compiler.  3.  Single character iterator optimizations in the JIT compiler.
919    
920    4.  Improved JIT compiler optimizations for character ranges.
921    
922    5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
923        Reported by Giuseppe D'Angelo.
924    
925    6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
926        of a line, was being set incorrectly in cases where .* appeared inside
927        atomic brackets at the start of a pattern, or where there was a subsequent
928        *PRUNE or *SKIP.
929    
930    7.  Improved instruction cache flush for POWER/PowerPC.
931        Patch by Daniel Richard G.
932    
933    8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
934        grep:
935    
936        (a) There is now no limit to the number of patterns to be matched.
937    
938        (b) An error is given if a pattern is too long.
939    
940        (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
941            are now supported.
942    
943        (d) --exclude-from and --include-from (multiple use) have been added.
944    
945        (e) Exclusions and inclusions now apply to all files and directories, not
946            just to those obtained from scanning a directory recursively.
947    
948        (f) Multiple uses of -f and --file-list are now supported.
949    
950        (g) In a Windows environment, the default for -d has been changed from
951            "read" (the GNU grep default) to "skip", because otherwise the presence
952            of a directory in the file list provokes an error.
953    
954        (h) The documentation has been revised and clarified in places.
955    
956    9.  Improve the matching speed of capturing brackets.
957    
958    10. Changed the meaning of \X so that it now matches a Unicode extended
959        grapheme cluster.
960    
961    11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
962        out POSIX threads when JIT support is configured.
963    
964    12. Added support for PCRE_STUDY_EXTRA_NEEDED.
965    
966    13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
967        structure could go wrong in environments where size_t is not the same size
968        as int.
969    
970    14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
971        set.
972    
973    15. The EBCDIC support had decayed; later updates to the code had included
974        explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
975        general tidy up of EBCDIC-related issues, and the documentation was also
976        not quite right. There is now a test that can be run on ASCII systems to
977        check some of the EBCDIC-related things (but is it not a full test).
978    
979    16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
980        in a small tidy to the code.
981    
982    17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
983    
984    18. If the --only-matching (-o) option in pcregrep is specified multiple
985        times, each one causes appropriate output. For example, -o1 -o2 outputs the
986        substrings matched by the 1st and 2nd capturing parentheses. A separating
987        string can be specified by --om-separator (default empty).
988    
989    19. Improving the first n character searches.
990    
991    20. Turn case lists for horizontal and vertical white space into macros so that
992        they are defined only once.
993    
994    21. This set of changes together give more compatible Unicode case-folding
995        behaviour for characters that have more than one other case when UCP
996        support is available.
997    
998        (a) The Unicode property table now has offsets into a new table of sets of
999            three or more characters that are case-equivalent. The MultiStage2.py
1000            script that generates these tables (the pcre_ucd.c file) now scans
1001            CaseFolding.txt instead of UnicodeData.txt for character case
1002            information.
1003    
1004        (b) The code for adding characters or ranges of characters to a character
1005            class has been abstracted into a generalized function that also handles
1006            case-independence. In UTF-mode with UCP support, this uses the new data
1007            to handle characters with more than one other case.
1008    
1009        (c) A bug that is fixed as a result of (b) is that codepoints less than 256
1010            whose other case is greater than 256 are now correctly matched
1011            caselessly. Previously, the high codepoint matched the low one, but not
1012            vice versa.
1013    
1014        (d) The processing of \h, \H, \v, and \ in character classes now makes use
1015            of the new class addition function, using character lists defined as
1016            macros alongside the case definitions of 20 above.
1017    
1018        (e) Caseless back references now work with characters that have more than
1019            one other case.
1020    
1021        (f) General caseless matching of characters with more than one other case
1022            is supported.
1023    
1024    22. Unicode character properties were updated from Unicode 6.2.0
1025    
1026    23. Improved CMake support under Windows. Patch by Daniel Richard G.
1027    
1028    24. Add support for 32-bit character strings, and UTF-32
1029    
1030    25. Major JIT compiler update (code refactoring and bugfixing).
1031        Experimental Sparc 32 support is added.
1032    
1033    26. Applied a modified version of Daniel Richard G's patch to create
1034        pcre.h.generic and config.h.generic by "make" instead of in the
1035        PrepareRelease script.
1036    
1037    27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
1038        pcre_compile.c when checking for a zero character.
1039    
1040    28. Introducing a native interface for JIT. Through this interface, the compiled
1041        machine code can be directly executed. The purpose of this interface is to
1042        provide fast pattern matching, so several sanity checks are not performed.
1043        However, feature tests are still performed. The new interface provides
1044        1.4x speedup compared to the old one.
1045    
1046    29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
1047        the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
1048        was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
1049    
1050    30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
1051        greater than 0x7fffffff (which cannot be represented in UTF-8, even under
1052        the "old" RFC 2279). Instead, it ended up passing a negative length to
1053        pcre_exec().
1054    
1055    31. Add support for GCC's visibility feature to hide internal functions.
1056    
1057    32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
1058        "unknown -C option" after outputting 0 or 1.
1059    
1060    33. There is now support for generating a code coverage report for the test
1061        suite in environments where gcc is the compiler and lcov is installed. This
1062        is mainly for the benefit of the developers.
1063    
1064    34. If PCRE is built with --enable-valgrind, certain memory regions are marked
1065        unaddressable using valgrind annotations, allowing valgrind to detect
1066        invalid memory accesses. This is mainly for the benefit of the developers.
1067    
1068    25. (*UTF) can now be used to start a pattern in any of the three libraries.
1069    
1070    26. Give configure error if --enable-cpp but no C++ compiler found.
1071    
1072    
1073  Version 8.31 06-July-2012  Version 8.31 06-July-2012
1074  -------------------------  -------------------------
# Line 1356  Version 7.9 11-Apr-09 Line 2413  Version 7.9 11-Apr-09
2413  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
2414      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
2415      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
2416      seems to be how GNU grep behaves.      seems to be how GNU grep behaves. [But see later change 40 for release
2417        8.33.]
2418    
2419  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
2420      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 1599  Version 7.7 07-May-08 Line 2657  Version 7.7 07-May-08
2657      containing () gave an internal compiling error instead of "reference to      containing () gave an internal compiling error instead of "reference to
2658      non-existent subpattern". Fortunately, when the pattern did exist, the      non-existent subpattern". Fortunately, when the pattern did exist, the
2659      compiled code was correct. (When scanning forwards to check for the      compiled code was correct. (When scanning forwards to check for the
2660      existencd of the subpattern, it was treating the data ']' as terminating      existence of the subpattern, it was treating the data ']' as terminating
2661      the class, so got the count wrong. When actually compiling, the reference      the class, so got the count wrong. When actually compiling, the reference
2662      was subsequently set up correctly.)      was subsequently set up correctly.)
2663    

Legend:
Removed from v.989  
changed lines
  Added in v.1596

  ViewVC Help
Powered by ViewVC 1.1.5