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

Diff of /code/trunk/ChangeLog

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

revision 740 by zherczeg, Mon Oct 31 06:10:14 2011 UTC revision 1604 by ph10, Tue Nov 17 17:27:17 2015 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.21  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 27-October-2015
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    39. An incorrect error "overran compiling workspace" was given if there were
149        exactly enough group forward references such that the last one extended
150        into the workspace safety margin. The next one would have expanded the
151        workspace. The test for overflow was not including the safety margin.
152    
153    40. A match limit issue is fixed in JIT which was found by Karl Skomski
154        with a custom LLVM fuzzer.
155    
156    41. Remove the use of /dev/null in testdata/testinput2, because it doesn't
157        work under Windows. (Why has it taken so long for anyone to notice?)
158    
159    42. In a character class such as [\W\p{Any}] where both a negative-type escape
160        ("not a word character") and a property escape were present, the property
161        escape was being ignored.
162    
163    43. Fix crash caused by very long (*MARK) or (*THEN) names.
164    
165    44. A sequence such as [[:punct:]b] that is, a POSIX character class followed
166        by a single ASCII character in a class item, was incorrectly compiled in
167        UCP mode. The POSIX class got lost, but only if the single character
168        followed it.
169    
170    
171    Version 8.37 28-April-2015
172    --------------------------
173    
174    1.  When an (*ACCEPT) is triggered inside capturing parentheses, it arranges
175        for those parentheses to be closed with whatever has been captured so far.
176        However, it was failing to mark any other groups between the hightest
177        capture so far and the currrent group as "unset". Thus, the ovector for
178        those groups contained whatever was previously there. An example is the
179        pattern /(x)|((*ACCEPT))/ when matched against "abcd".
180    
181    2.  If an assertion condition was quantified with a minimum of zero (an odd
182        thing to do, but it happened), SIGSEGV or other misbehaviour could occur.
183    
184    3.  If a pattern in pcretest input had the P (POSIX) modifier followed by an
185        unrecognized modifier, a crash could occur.
186    
187    4.  An attempt to do global matching in pcretest with a zero-length ovector
188        caused a crash.
189    
190    5.  Fixed a memory leak during matching that could occur for a subpattern
191        subroutine call (recursive or otherwise) if the number of captured groups
192        that had to be saved was greater than ten.
193    
194    6.  Catch a bad opcode during auto-possessification after compiling a bad UTF
195        string with NO_UTF_CHECK. This is a tidyup, not a bug fix, as passing bad
196        UTF with NO_UTF_CHECK is documented as having an undefined outcome.
197    
198    7.  A UTF pattern containing a "not" match of a non-ASCII character and a
199        subroutine reference could loop at compile time. Example: /[^\xff]((?1))/.
200    
201    8. When a pattern is compiled, it remembers the highest back reference so that
202       when matching, if the ovector is too small, extra memory can be obtained to
203       use instead. A conditional subpattern whose condition is a check on a
204       capture having happened, such as, for example in the pattern
205       /^(?:(a)|b)(?(1)A|B)/, is another kind of back reference, but it was not
206       setting the highest backreference number. This mattered only if pcre_exec()
207       was called with an ovector that was too small to hold the capture, and there
208       was no other kind of back reference (a situation which is probably quite
209       rare). The effect of the bug was that the condition was always treated as
210       FALSE when the capture could not be consulted, leading to a incorrect
211       behaviour by pcre_exec(). This bug has been fixed.
212    
213    9. A reference to a duplicated named group (either a back reference or a test
214       for being set in a conditional) that occurred in a part of the pattern where
215       PCRE_DUPNAMES was not set caused the amount of memory needed for the pattern
216       to be incorrectly calculated, leading to overwriting.
217    
218    10. A mutually recursive set of back references such as (\2)(\1) caused a
219        segfault at study time (while trying to find the minimum matching length).
220        The infinite loop is now broken (with the minimum length unset, that is,
221        zero).
222    
223    11. If an assertion that was used as a condition was quantified with a minimum
224        of zero, matching went wrong. In particular, if the whole group had
225        unlimited repetition and could match an empty string, a segfault was
226        likely. The pattern (?(?=0)?)+ is an example that caused this. Perl allows
227        assertions to be quantified, but not if they are being used as conditions,
228        so the above pattern is faulted by Perl. PCRE has now been changed so that
229        it also rejects such patterns.
230    
231    12. A possessive capturing group such as (a)*+ with a minimum repeat of zero
232        failed to allow the zero-repeat case if pcre2_exec() was called with an
233        ovector too small to capture the group.
234    
235    13. Fixed two bugs in pcretest that were discovered by fuzzing and reported by
236        Red Hat Product Security:
237    
238        (a) A crash if /K and /F were both set with the option to save the compiled
239        pattern.
240    
241        (b) Another crash if the option to print captured substrings in a callout
242        was combined with setting a null ovector, for example \O\C+ as a subject
243        string.
244    
245    14. A pattern such as "((?2){0,1999}())?", which has a group containing a
246        forward reference repeated a large (but limited) number of times within a
247        repeated outer group that has a zero minimum quantifier, caused incorrect
248        code to be compiled, leading to the error "internal error:
249        previously-checked referenced subpattern not found" when an incorrect
250        memory address was read. This bug was reported as "heap overflow",
251        discovered by Kai Lu of Fortinet's FortiGuard Labs and given the CVE number
252        CVE-2015-2325.
253    
254    23. A pattern such as "((?+1)(\1))/" containing a forward reference subroutine
255        call within a group that also contained a recursive back reference caused
256        incorrect code to be compiled. This bug was reported as "heap overflow",
257        discovered by Kai Lu of Fortinet's FortiGuard Labs, and given the CVE
258        number CVE-2015-2326.
259    
260    24. Computing the size of the JIT read-only data in advance has been a source
261        of various issues, and new ones are still appear unfortunately. To fix
262        existing and future issues, size computation is eliminated from the code,
263        and replaced by on-demand memory allocation.
264    
265    25. A pattern such as /(?i)[A-`]/, where characters in the other case are
266        adjacent to the end of the range, and the range contained characters with
267        more than one other case, caused incorrect behaviour when compiled in UTF
268        mode. In that example, the range a-j was left out of the class.
269    
270    26. Fix JIT compilation of conditional blocks, which assertion
271        is converted to (*FAIL). E.g: /(?(?!))/.
272    
273    27. The pattern /(?(?!)^)/ caused references to random memory. This bug was
274        discovered by the LLVM fuzzer.
275    
276    28. The assertion (?!) is optimized to (*FAIL). This was not handled correctly
277        when this assertion was used as a condition, for example (?(?!)a|b). In
278        pcre2_match() it worked by luck; in pcre2_dfa_match() it gave an incorrect
279        error about an unsupported item.
280    
281    29. For some types of pattern, for example /Z*(|d*){216}/, the auto-
282        possessification code could take exponential time to complete. A recursion
283        depth limit of 1000 has been imposed to limit the resources used by this
284        optimization.
285    
286    30. A pattern such as /(*UTF)[\S\V\H]/, which contains a negated special class
287        such as \S in non-UCP mode, explicit wide characters (> 255) can be ignored
288        because \S ensures they are all in the class. The code for doing this was
289        interacting badly with the code for computing the amount of space needed to
290        compile the pattern, leading to a buffer overflow. This bug was discovered
291        by the LLVM fuzzer.
292    
293    31. A pattern such as /((?2)+)((?1))/ which has mutual recursion nested inside
294        other kinds of group caused stack overflow at compile time. This bug was
295        discovered by the LLVM fuzzer.
296    
297    32. A pattern such as /(?1)(?#?'){8}(a)/ which had a parenthesized comment
298        between a subroutine call and its quantifier was incorrectly compiled,
299        leading to buffer overflow or other errors. This bug was discovered by the
300        LLVM fuzzer.
301    
302    33. The illegal pattern /(?(?<E>.*!.*)?)/ was not being diagnosed as missing an
303        assertion after (?(. The code was failing to check the character after
304        (?(?< for the ! or = that would indicate a lookbehind assertion. This bug
305        was discovered by the LLVM fuzzer.
306    
307    34. A pattern such as /X((?2)()*+){2}+/ which has a possessive quantifier with
308        a fixed maximum following a group that contains a subroutine reference was
309        incorrectly compiled and could trigger buffer overflow. This bug was
310        discovered by the LLVM fuzzer.
311    
312    35. A mutual recursion within a lookbehind assertion such as (?<=((?2))((?1)))
313        caused a stack overflow instead of the diagnosis of a non-fixed length
314        lookbehind assertion. This bug was discovered by the LLVM fuzzer.
315    
316    36. The use of \K in a positive lookbehind assertion in a non-anchored pattern
317        (e.g. /(?<=\Ka)/) could make pcregrep loop.
318    
319    37. There was a similar problem to 36 in pcretest for global matches.
320    
321    38. If a greedy quantified \X was preceded by \C in UTF mode (e.g. \C\X*),
322        and a subsequent item in the pattern caused a non-match, backtracking over
323        the repeated \X did not stop, but carried on past the start of the subject,
324        causing reference to random memory and/or a segfault. There were also some
325        other cases where backtracking after \C could crash. This set of bugs was
326        discovered by the LLVM fuzzer.
327    
328    39. The function for finding the minimum length of a matching string could take
329        a very long time if mutual recursion was present many times in a pattern,
330        for example, /((?2){73}(?2))((?1))/. A better mutual recursion detection
331        method has been implemented. This infelicity was discovered by the LLVM
332        fuzzer.
333    
334    40. Static linking against the PCRE library using the pkg-config module was
335        failing on missing pthread symbols.
336    
337    
338    Version 8.36 26-September-2014
339    ------------------------------
340    
341    1.  Got rid of some compiler warnings in the C++ modules that were shown up by
342        -Wmissing-field-initializers and -Wunused-parameter.
343    
344    2.  The tests for quantifiers being too big (greater than 65535) were being
345        applied after reading the number, and stupidly assuming that integer
346        overflow would give a negative number. The tests are now applied as the
347        numbers are read.
348    
349    3.  Tidy code in pcre_exec.c where two branches that used to be different are
350        now the same.
351    
352    4.  The JIT compiler did not generate match limit checks for certain
353        bracketed expressions with quantifiers. This may lead to exponential
354        backtracking, instead of returning with PCRE_ERROR_MATCHLIMIT. This
355        issue should be resolved now.
356    
357    5.  Fixed an issue, which occures when nested alternatives are optimized
358        with table jumps.
359    
360    6.  Inserted two casts and changed some ints to size_t in the light of some
361        reported 64-bit compiler warnings (Bugzilla 1477).
362    
363    7.  Fixed a bug concerned with zero-minimum possessive groups that could match
364        an empty string, which sometimes were behaving incorrectly in the
365        interpreter (though correctly in the JIT matcher). This pcretest input is
366        an example:
367    
368          '\A(?:[^"]++|"(?:[^"]*+|"")*+")++'
369          NON QUOTED "QUOT""ED" AFTER "NOT MATCHED
370    
371        the interpreter was reporting a match of 'NON QUOTED ' only, whereas the
372        JIT matcher and Perl both matched 'NON QUOTED "QUOT""ED" AFTER '. The test
373        for an empty string was breaking the inner loop and carrying on at a lower
374        level, when possessive repeated groups should always return to a higher
375        level as they have no backtrack points in them. The empty string test now
376        occurs at the outer level.
377    
378    8.  Fixed a bug that was incorrectly auto-possessifying \w+ in the pattern
379        ^\w+(?>\s*)(?<=\w) which caused it not to match "test test".
380    
381    9.  Give a compile-time error for \o{} (as Perl does) and for \x{} (which Perl
382        doesn't).
383    
384    10. Change 8.34/15 introduced a bug that caused the amount of memory needed
385        to hold a pattern to be incorrectly computed (too small) when there were
386        named back references to duplicated names. This could cause "internal
387        error: code overflow" or "double free or corruption" or other memory
388        handling errors.
389    
390    11. When named subpatterns had the same prefixes, back references could be
391        confused. For example, in this pattern:
392    
393          /(?P<Name>a)?(?P<Name2>b)?(?(<Name>)c|d)*l/
394    
395        the reference to 'Name' was incorrectly treated as a reference to a
396        duplicate name.
397    
398    12. A pattern such as /^s?c/mi8 where the optional character has more than
399        one "other case" was incorrectly compiled such that it would only try to
400        match starting at "c".
401    
402    13. When a pattern starting with \s was studied, VT was not included in the
403        list of possible starting characters; this should have been part of the
404        8.34/18 patch.
405    
406    14. If a character class started [\Qx]... where x is any character, the class
407        was incorrectly terminated at the ].
408    
409    15. If a pattern that started with a caseless match for a character with more
410        than one "other case" was studied, PCRE did not set up the starting code
411        unit bit map for the list of possible characters. Now it does. This is an
412        optimization improvement, not a bug fix.
413    
414    16. The Unicode data tables have been updated to Unicode 7.0.0.
415    
416    17. Fixed a number of memory leaks in pcregrep.
417    
418    18. Avoid a compiler warning (from some compilers) for a function call with
419        a cast that removes "const" from an lvalue by using an intermediate
420        variable (to which the compiler does not object).
421    
422    19. Incorrect code was compiled if a group that contained an internal recursive
423        back reference was optional (had quantifier with a minimum of zero). This
424        example compiled incorrect code: /(((a\2)|(a*)\g<-1>))*/ and other examples
425        caused segmentation faults because of stack overflows at compile time.
426    
427    20. A pattern such as /((?(R)a|(?1)))+/, which contains a recursion within a
428        group that is quantified with an indefinite repeat, caused a compile-time
429        loop which used up all the system stack and provoked a segmentation fault.
430        This was not the same bug as 19 above.
431    
432    21. Add PCRECPP_EXP_DECL declaration to operator<< in pcre_stringpiece.h.
433        Patch by Mike Frysinger.
434    
435    
436    Version 8.35 04-April-2014
437    --------------------------
438    
439    1.  A new flag is set, when property checks are present in an XCLASS.
440        When this flag is not set, PCRE can perform certain optimizations
441        such as studying these XCLASS-es.
442    
443    2.  The auto-possessification of character sets were improved: a normal
444        and an extended character set can be compared now. Furthermore
445        the JIT compiler optimizes more character set checks.
446    
447    3.  Got rid of some compiler warnings for potentially uninitialized variables
448        that show up only when compiled with -O2.
449    
450    4.  A pattern such as (?=ab\K) that uses \K in an assertion can set the start
451        of a match later then the end of the match. The pcretest program was not
452        handling the case sensibly - it was outputting from the start to the next
453        binary zero. It now reports this situation in a message, and outputs the
454        text from the end to the start.
455    
456    5.  Fast forward search is improved in JIT. Instead of the first three
457        characters, any three characters with fixed position can be searched.
458        Search order: first, last, middle.
459    
460    6.  Improve character range checks in JIT. Characters are read by an inprecise
461        function now, which returns with an unknown value if the character code is
462        above a certain threshold (e.g: 256). The only limitation is that the value
463        must be bigger than the threshold as well. This function is useful when
464        the characters above the threshold are handled in the same way.
465    
466    7.  The macros whose names start with RAWUCHAR are placeholders for a future
467        mode in which only the bottom 21 bits of 32-bit data items are used. To
468        make this more memorable for those maintaining the code, the names have
469        been changed to start with UCHAR21, and an extensive comment has been added
470        to their definition.
471    
472    8.  Add missing (new) files sljitNativeTILEGX.c and sljitNativeTILEGX-encoder.c
473        to the export list in Makefile.am (they were accidentally omitted from the
474        8.34 tarball).
475    
476    9.  The informational output from pcretest used the phrase "starting byte set"
477        which is inappropriate for the 16-bit and 32-bit libraries. As the output
478        for "first char" and "need char" really means "non-UTF-char", I've changed
479        "byte" to "char", and slightly reworded the output. The documentation about
480        these values has also been (I hope) clarified.
481    
482    10. Another JIT related optimization: use table jumps for selecting the correct
483        backtracking path, when more than four alternatives are present inside a
484        bracket.
485    
486    11. Empty match is not possible, when the minimum length is greater than zero,
487        and there is no \K in the pattern. JIT should avoid empty match checks in
488        such cases.
489    
490    12. In a caseless character class with UCP support, when a character with more
491        than one alternative case was not the first character of a range, not all
492        the alternative cases were added to the class. For example, s and \x{17f}
493        are both alternative cases for S: the class [RST] was handled correctly,
494        but [R-T] was not.
495    
496    13. The configure.ac file always checked for pthread support when JIT was
497        enabled. This is not used in Windows, so I have put this test inside a
498        check for the presence of windows.h (which was already tested for).
499    
500    14. Improve pattern prefix search by a simplified Boyer-Moore algorithm in JIT.
501        The algorithm provides a way to skip certain starting offsets, and usually
502        faster than linear prefix searches.
503    
504    15. Change 13 for 8.20 updated RunTest to check for the 'fr' locale as well
505        as for 'fr_FR' and 'french'. For some reason, however, it then used the
506        Windows-specific input and output files, which have 'french' screwed in.
507        So this could never have worked. One of the problems with locales is that
508        they aren't always the same. I have now updated RunTest so that it checks
509        the output of the locale test (test 3) against three different output
510        files, and it allows the test to pass if any one of them matches. With luck
511        this should make the test pass on some versions of Solaris where it was
512        failing. Because of the uncertainty, the script did not used to stop if
513        test 3 failed; it now does. If further versions of a French locale ever
514        come to light, they can now easily be added.
515    
516    16. If --with-pcregrep-bufsize was given a non-integer value such as "50K",
517        there was a message during ./configure, but it did not stop. This now
518        provokes an error. The invalid example in README has been corrected.
519        If a value less than the minimum is given, the minimum value has always
520        been used, but now a warning is given.
521    
522    17. If --enable-bsr-anycrlf was set, the special 16/32-bit test failed. This
523        was a bug in the test system, which is now fixed. Also, the list of various
524        configurations that are tested for each release did not have one with both
525        16/32 bits and --enable-bar-anycrlf. It now does.
526    
527    18. pcretest was missing "-C bsr" for displaying the \R default setting.
528    
529    19. Little endian PowerPC systems are supported now by the JIT compiler.
530    
531    20. The fast forward newline mechanism could enter to an infinite loop on
532        certain invalid UTF-8 input. Although we don't support these cases
533        this issue can be fixed by a performance optimization.
534    
535    21. Change 33 of 8.34 is not sufficient to ensure stack safety because it does
536        not take account if existing stack usage. There is now a new global
537        variable called pcre_stack_guard that can be set to point to an external
538        function to check stack availability. It is called at the start of
539        processing every parenthesized group.
540    
541    22. A typo in the code meant that in ungreedy mode the max/min qualifier
542        behaved like a min-possessive qualifier, and, for example, /a{1,3}b/U did
543        not match "ab".
544    
545    23. When UTF was disabled, the JIT program reported some incorrect compile
546        errors. These messages are silenced now.
547    
548    24. Experimental support for ARM-64 and MIPS-64 has been added to the JIT
549        compiler.
550    
551    25. Change all the temporary files used in RunGrepTest to be different to those
552        used by RunTest so that the tests can be run simultaneously, for example by
553        "make -j check".
554    
555    
556    Version 8.34 15-December-2013
557    -----------------------------
558    
559    1.  Add pcre[16|32]_jit_free_unused_memory to forcibly free unused JIT
560        executable memory. Patch inspired by Carsten Klein.
561    
562    2.  ./configure --enable-coverage defined SUPPORT_GCOV in config.h, although
563        this macro is never tested and has no effect, because the work to support
564        coverage involves only compiling and linking options and special targets in
565        the Makefile. The comment in config.h implied that defining the macro would
566        enable coverage support, which is totally false. There was also support for
567        setting this macro in the CMake files (my fault, I just copied it from
568        configure). SUPPORT_GCOV has now been removed.
569    
570    3.  Make a small performance improvement in strlen16() and strlen32() in
571        pcretest.
572    
573    4.  Change 36 for 8.33 left some unreachable statements in pcre_exec.c,
574        detected by the Solaris compiler (gcc doesn't seem to be able to diagnose
575        these cases). There was also one in pcretest.c.
576    
577    5.  Cleaned up a "may be uninitialized" compiler warning in pcre_exec.c.
578    
579    6.  In UTF mode, the code for checking whether a group could match an empty
580        string (which is used for indefinitely repeated groups to allow for
581        breaking an infinite loop) was broken when the group contained a repeated
582        negated single-character class with a character that occupied more than one
583        data item and had a minimum repetition of zero (for example, [^\x{100}]* in
584        UTF-8 mode). The effect was undefined: the group might or might not be
585        deemed as matching an empty string, or the program might have crashed.
586    
587    7.  The code for checking whether a group could match an empty string was not
588        recognizing that \h, \H, \v, \V, and \R must match a character.
589    
590    8.  Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
591        an empty string. If it can, pcretest shows this in its information output.
592    
593    9.  Fixed two related bugs that applied to Unicode extended grapheme clusters
594        that were repeated with a maximizing qualifier (e.g. \X* or \X{2,5}) when
595        matched by pcre_exec() without using JIT:
596    
597        (a) If the rest of the pattern did not match after a maximal run of
598            grapheme clusters, the code for backing up to try with fewer of them
599            did not always back up over a full grapheme when characters that do not
600            have the modifier quality were involved, e.g. Hangul syllables.
601    
602        (b) If the match point in a subject started with modifier character, and
603            there was no match, the code could incorrectly back up beyond the match
604            point, and potentially beyond the first character in the subject,
605            leading to a segfault or an incorrect match result.
606    
607    10. A conditional group with an assertion condition could lead to PCRE
608        recording an incorrect first data item for a match if no other first data
609        item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
610        first data item, and therefore matched "ca" after "c" instead of at the
611        start.
612    
613    11. Change 40 for 8.33 (allowing pcregrep to find empty strings) showed up a
614        bug that caused the command "echo a | ./pcregrep -M '|a'" to loop.
615    
616    12. The source of pcregrep now includes z/OS-specific code so that it can be
617        compiled for z/OS as part of the special z/OS distribution.
618    
619    13. Added the -T and -TM options to pcretest.
620    
621    14. The code in pcre_compile.c for creating the table of named capturing groups
622        has been refactored. Instead of creating the table dynamically during the
623        actual compiling pass, the information is remembered during the pre-compile
624        pass (on the stack unless there are more than 20 named groups, in which
625        case malloc() is used) and the whole table is created before the actual
626        compile happens. This has simplified the code (it is now nearly 150 lines
627        shorter) and prepared the way for better handling of references to groups
628        with duplicate names.
629    
630    15. A back reference to a named subpattern when there is more than one of the
631        same name now checks them in the order in which they appear in the pattern.
632        The first one that is set is used for the reference. Previously only the
633        first one was inspected. This change makes PCRE more compatible with Perl.
634    
635    16. Unicode character properties were updated from Unicode 6.3.0.
636    
637    17. The compile-time code for auto-possessification has been refactored, based
638        on a patch by Zoltan Herczeg. It now happens after instead of during
639        compilation. The code is cleaner, and more cases are handled. The option
640        PCRE_NO_AUTO_POSSESS is added for testing purposes, and the -O and /O
641        options in pcretest are provided to set it. It can also be set by
642        (*NO_AUTO_POSSESS) at the start of a pattern.
643    
644    18. The character VT has been added to the default ("C" locale) set of
645        characters that match \s and are generally treated as white space,
646        following this same change in Perl 5.18. There is now no difference between
647        "Perl space" and "POSIX space". Whether VT is treated as white space in
648        other locales depends on the locale.
649    
650    19. The code for checking named groups as conditions, either for being set or
651        for being recursed, has been refactored (this is related to 14 and 15
652        above). Processing unduplicated named groups should now be as fast at
653        numerical groups, and processing duplicated groups should be faster than
654        before.
655    
656    20. Two patches to the CMake build system, by Alexander Barkov:
657    
658          (1) Replace the "source" command by "." in CMakeLists.txt because
659              "source" is a bash-ism.
660    
661          (2) Add missing HAVE_STDINT_H and HAVE_INTTYPES_H to config-cmake.h.in;
662              without these the CMake build does not work on Solaris.
663    
664    21. Perl has changed its handling of \8 and \9. If there is no previously
665        encountered capturing group of those numbers, they are treated as the
666        literal characters 8 and 9 instead of a binary zero followed by the
667        literals. PCRE now does the same.
668    
669    22. Following Perl, added \o{} to specify codepoints in octal, making it
670        possible to specify values greater than 0777 and also making them
671        unambiguous.
672    
673    23. Perl now gives an error for missing closing braces after \x{... instead of
674        treating the string as literal. PCRE now does the same.
675    
676    24. RunTest used to grumble if an inappropriate test was selected explicitly,
677        but just skip it when running all tests. This make it awkward to run ranges
678        of tests when one of them was inappropriate. Now it just skips any
679        inappropriate tests, as it always did when running all tests.
680    
681    25. If PCRE_AUTO_CALLOUT and PCRE_UCP were set for a pattern that contained
682        character types such as \d or \w, too many callouts were inserted, and the
683        data that they returned was rubbish.
684    
685    26. In UCP mode, \s was not matching two of the characters that Perl matches,
686        namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
687        were matched by \h. The code has now been refactored so that the lists of
688        the horizontal and vertical whitespace characters used for \h and \v (which
689        are defined only in one place) are now also used for \s.
690    
691    27. Add JIT support for the 64 bit TileGX architecture.
692        Patch by Jiong Wang (Tilera Corporation).
693    
694    28. Possessive quantifiers for classes (both explicit and automatically
695        generated) now use special opcodes instead of wrapping in ONCE brackets.
696    
697    29. Whereas an item such as A{4}+ ignored the possessivenes of the quantifier
698        (because it's meaningless), this was not happening when PCRE_CASELESS was
699        set. Not wrong, but inefficient.
700    
701    30. Updated perltest.pl to add /u (force Unicode mode) when /W (use Unicode
702        properties for \w, \d, etc) is present in a test regex. Otherwise if the
703        test contains no characters greater than 255, Perl doesn't realise it
704        should be using Unicode semantics.
705    
706    31. Upgraded the handling of the POSIX classes [:graph:], [:print:], and
707        [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
708        does in Unicode mode.
709    
710    32. Added the "forbid" facility to pcretest so that putting tests into the
711        wrong test files can sometimes be quickly detected.
712    
713    33. There is now a limit (default 250) on the depth of nesting of parentheses.
714        This limit is imposed to control the amount of system stack used at compile
715        time. It can be changed at build time by --with-parens-nest-limit=xxx or
716        the equivalent in CMake.
717    
718    34. Character classes such as [A-\d] or [a-[:digit:]] now cause compile-time
719        errors. Perl warns for these when in warning mode, but PCRE has no facility
720        for giving warnings.
721    
722    35. Change 34 for 8.13 allowed quantifiers on assertions, because Perl does.
723        However, this was not working for (?!) because it is optimized to (*FAIL),
724        for which PCRE does not allow quantifiers. The optimization is now disabled
725        when a quantifier follows (?!). I can't see any use for this, but it makes
726        things uniform.
727    
728    36. Perl no longer allows group names to start with digits, so I have made this
729        change also in PCRE. It simplifies the code a bit.
730    
731    37. In extended mode, Perl ignores spaces before a + that indicates a
732        possessive quantifier. PCRE allowed a space before the quantifier, but not
733        before the possessive +. It now does.
734    
735    38. The use of \K (reset reported match start) within a repeated possessive
736        group such as (a\Kb)*+ was not working.
737    
738    40. Document that the same character tables must be used at compile time and
739        run time, and that the facility to pass tables to pcre_exec() and
740        pcre_dfa_exec() is for use only with saved/restored patterns.
741    
742    41. Applied Jeff Trawick's patch CMakeLists.txt, which "provides two new
743        features for Builds with MSVC:
744    
745        1. Support pcre.rc and/or pcreposix.rc (as is already done for MinGW
746           builds). The .rc files can be used to set FileDescription and many other
747           attributes.
748    
749        2. Add an option (-DINSTALL_MSVC_PDB) to enable installation of .pdb files.
750           This allows higher-level build scripts which want .pdb files to avoid
751           hard-coding the exact files needed."
752    
753    42. Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
754        mean "start of word" and "end of word", respectively, as a transition aid.
755    
756    43. A minimizing repeat of a class containing codepoints greater than 255 in
757        non-UTF 16-bit or 32-bit modes caused an internal error when PCRE was
758        compiled to use the heap for recursion.
759    
760    44. Got rid of some compiler warnings for unused variables when UTF but not UCP
761        is configured.
762    
763    
764    Version 8.33 28-May-2013
765    ------------------------
766    
767    1.  Added 'U' to some constants that are compared to unsigned integers, to
768        avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
769        variables that are added to signed variables, to ensure the result is
770        signed and can be negated.
771    
772    2.  Applied patch by Daniel Richard G for quashing MSVC warnings to the
773        CMake config files.
774    
775    3.  Revise the creation of config.h.generic so that all boolean macros are
776        #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
777        overriding via -D on the command line possible.
778    
779    4.  Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
780        to unsigned int is reported to make a quite noticeable speed difference in
781        a specific Windows environment. Testing on Linux did also appear to show
782        some benefit (and it is clearly not harmful). Also fixed the definition of
783        Xop which should be unsigned.
784    
785    5.  Related to (4), changing the definition of the intermediate variable cc
786        in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
787        improvements.
788    
789    6.  Fix forward search in JIT when link size is 3 or greater. Also removed some
790        unnecessary spaces.
791    
792    7.  Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
793        and later.
794    
795    8.  Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
796    
797    9.  Optimizing fast_forward_start_bits in JIT.
798    
799    10. Adding support for callouts in JIT, and fixing some issues revealed
800        during this work. Namely:
801    
802        (a) Unoptimized capturing brackets incorrectly reset on backtrack.
803    
804        (b) Minimum length was not checked before the matching is started.
805    
806    11. The value of capture_last that is passed to callouts was incorrect in some
807        cases when there was a capture on one path that was subsequently abandoned
808        after a backtrack. Also, the capture_last value is now reset after a
809        recursion, since all captures are also reset in this case.
810    
811    12. The interpreter no longer returns the "too many substrings" error in the
812        case when an overflowing capture is in a branch that is subsequently
813        abandoned after a backtrack.
814    
815    13. In the pathological case when an offset vector of size 2 is used, pcretest
816        now prints out the matched string after a yield of 0 or 1.
817    
818    14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
819        Only supported by the JIT compiler at the moment.
820    
821    15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
822    
823    16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
824        offset of the starting point of the matching process, provided the offsets
825        vector is large enough.
826    
827    17. The \A escape now records a lookbehind value of 1, though its execution
828        does not actually inspect the previous character. This is to ensure that,
829        in partial multi-segment matching, at least one character from the old
830        segment is retained when a new segment is processed. Otherwise, if there
831        are no lookbehinds in the pattern, \A might match incorrectly at the start
832        of a new segment.
833    
834    18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
835    
836    19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
837        gives some modest performance improvement in 8-bit mode.
838    
839    20. Added the PCRE-specific property \p{Xuc} for matching characters that can
840        be expressed in certain programming languages using Universal Character
841        Names.
842    
843    21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
844        which points out that "non characters" are not "characters that may not
845        appear in Unicode strings" but rather "characters that are reserved for
846        internal use and have only local meaning".
847    
848    22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
849        there was a conditional group that depended on an assertion, if the
850        assertion was false, the callout that immediately followed the alternation
851        in the condition was skipped when pcre_exec() was used for matching.
852    
853    23. Allow an explicit callout to be inserted before an assertion that is the
854        condition for a conditional group, for compatibility with automatic
855        callouts, which always insert a callout at this point.
856    
857    24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
858        confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
859    
860    25. (*PRUNE) is now supported by the JIT compiler.
861    
862    26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
863    
864    27. Fix the case where there are two or more SKIPs with arguments that may be
865        ignored.
866    
867    28. (*SKIP) is now supported by the JIT compiler.
868    
869    29. (*THEN) is now supported by the JIT compiler.
870    
871    30. Update RunTest with additional test selector options.
872    
873    31. The way PCRE handles backtracking verbs has been changed in two ways.
874    
875        (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
876        SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
877        backtracking. In some cases this makes it more Perl-compatible, but Perl's
878        rather obscure rules do not always do the same thing.
879    
880        (2) Previously, backtracking verbs were confined within assertions. This is
881        no longer the case for positive assertions, except for (*ACCEPT). Again,
882        this sometimes improves Perl compatibility, and sometimes does not.
883    
884    32. A number of tests that were in test 2 because Perl did things differently
885        have been moved to test 1, because either Perl or PCRE has changed, and
886        these tests are now compatible.
887    
888    32. Backtracking control verbs are now handled in the same way in JIT and
889        interpreter.
890    
891    33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
892        contained a forward subroutine reference caused a compile error.
893    
894    34. Auto-detect and optimize limited repetitions in JIT.
895    
896    35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
897        blocking (*UTF) etc.
898    
899    36. In the interpreter, maximizing pattern repetitions for characters and
900        character types now use tail recursion, which reduces stack usage.
901    
902    37. The value of the max lookbehind was not correctly preserved if a compiled
903        and saved regex was reloaded on a host of different endianness.
904    
905    38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
906        of the compiled pattern block, expand the flags field from 16 to 32 bits
907        because it was almost full.
908    
909    39. Try madvise first before posix_madvise.
910    
911    40. Change 7 for PCRE 7.9 made it impossible for pcregrep to find empty lines
912        with a pattern such as ^$. It has taken 4 years for anybody to notice! The
913        original change locked out all matches of empty strings. This has been
914        changed so that one match of an empty string per line is recognized.
915        Subsequent searches on the same line (for colouring or for --only-matching,
916        for example) do not recognize empty strings.
917    
918    41. Applied a user patch to fix a number of spelling mistakes in comments.
919    
920    42. Data lines longer than 65536 caused pcretest to crash.
921    
922    43. Clarified the data type for length and startoffset arguments for pcre_exec
923        and pcre_dfa_exec in the function-specific man pages, where they were
924        explicitly stated to be in bytes, never having been updated. I also added
925        some clarification to the pcreapi man page.
926    
927    44. A call to pcre_dfa_exec() with an output vector size less than 2 caused
928        a segmentation fault.
929    
930    
931    Version 8.32 30-November-2012
932    -----------------------------
933    
934    1.  Improved JIT compiler optimizations for first character search and single
935        character iterators.
936    
937    2.  Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
938        Patch by Daniel Richard G.
939    
940    3.  Single character iterator optimizations in the JIT compiler.
941    
942    4.  Improved JIT compiler optimizations for character ranges.
943    
944    5.  Rename the "leave" variable names to "quit" to improve WinCE compatibility.
945        Reported by Giuseppe D'Angelo.
946    
947    6.  The PCRE_STARTLINE bit, indicating that a match can occur only at the start
948        of a line, was being set incorrectly in cases where .* appeared inside
949        atomic brackets at the start of a pattern, or where there was a subsequent
950        *PRUNE or *SKIP.
951    
952    7.  Improved instruction cache flush for POWER/PowerPC.
953        Patch by Daniel Richard G.
954    
955    8.  Fixed a number of issues in pcregrep, making it more compatible with GNU
956        grep:
957    
958        (a) There is now no limit to the number of patterns to be matched.
959    
960        (b) An error is given if a pattern is too long.
961    
962        (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
963            are now supported.
964    
965        (d) --exclude-from and --include-from (multiple use) have been added.
966    
967        (e) Exclusions and inclusions now apply to all files and directories, not
968            just to those obtained from scanning a directory recursively.
969    
970        (f) Multiple uses of -f and --file-list are now supported.
971    
972        (g) In a Windows environment, the default for -d has been changed from
973            "read" (the GNU grep default) to "skip", because otherwise the presence
974            of a directory in the file list provokes an error.
975    
976        (h) The documentation has been revised and clarified in places.
977    
978    9.  Improve the matching speed of capturing brackets.
979    
980    10. Changed the meaning of \X so that it now matches a Unicode extended
981        grapheme cluster.
982    
983    11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
984        out POSIX threads when JIT support is configured.
985    
986    12. Added support for PCRE_STUDY_EXTRA_NEEDED.
987    
988    13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
989        structure could go wrong in environments where size_t is not the same size
990        as int.
991    
992    14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
993        set.
994    
995    15. The EBCDIC support had decayed; later updates to the code had included
996        explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
997        general tidy up of EBCDIC-related issues, and the documentation was also
998        not quite right. There is now a test that can be run on ASCII systems to
999        check some of the EBCDIC-related things (but is it not a full test).
1000    
1001    16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
1002        in a small tidy to the code.
1003    
1004    17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
1005    
1006    18. If the --only-matching (-o) option in pcregrep is specified multiple
1007        times, each one causes appropriate output. For example, -o1 -o2 outputs the
1008        substrings matched by the 1st and 2nd capturing parentheses. A separating
1009        string can be specified by --om-separator (default empty).
1010    
1011    19. Improving the first n character searches.
1012    
1013    20. Turn case lists for horizontal and vertical white space into macros so that
1014        they are defined only once.
1015    
1016    21. This set of changes together give more compatible Unicode case-folding
1017        behaviour for characters that have more than one other case when UCP
1018        support is available.
1019    
1020        (a) The Unicode property table now has offsets into a new table of sets of
1021            three or more characters that are case-equivalent. The MultiStage2.py
1022            script that generates these tables (the pcre_ucd.c file) now scans
1023            CaseFolding.txt instead of UnicodeData.txt for character case
1024            information.
1025    
1026        (b) The code for adding characters or ranges of characters to a character
1027            class has been abstracted into a generalized function that also handles
1028            case-independence. In UTF-mode with UCP support, this uses the new data
1029            to handle characters with more than one other case.
1030    
1031        (c) A bug that is fixed as a result of (b) is that codepoints less than 256
1032            whose other case is greater than 256 are now correctly matched
1033            caselessly. Previously, the high codepoint matched the low one, but not
1034            vice versa.
1035    
1036        (d) The processing of \h, \H, \v, and \ in character classes now makes use
1037            of the new class addition function, using character lists defined as
1038            macros alongside the case definitions of 20 above.
1039    
1040        (e) Caseless back references now work with characters that have more than
1041            one other case.
1042    
1043        (f) General caseless matching of characters with more than one other case
1044            is supported.
1045    
1046    22. Unicode character properties were updated from Unicode 6.2.0
1047    
1048    23. Improved CMake support under Windows. Patch by Daniel Richard G.
1049    
1050    24. Add support for 32-bit character strings, and UTF-32
1051    
1052    25. Major JIT compiler update (code refactoring and bugfixing).
1053        Experimental Sparc 32 support is added.
1054    
1055    26. Applied a modified version of Daniel Richard G's patch to create
1056        pcre.h.generic and config.h.generic by "make" instead of in the
1057        PrepareRelease script.
1058    
1059    27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
1060        pcre_compile.c when checking for a zero character.
1061    
1062    28. Introducing a native interface for JIT. Through this interface, the compiled
1063        machine code can be directly executed. The purpose of this interface is to
1064        provide fast pattern matching, so several sanity checks are not performed.
1065        However, feature tests are still performed. The new interface provides
1066        1.4x speedup compared to the old one.
1067    
1068    29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
1069        the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
1070        was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
1071    
1072    30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
1073        greater than 0x7fffffff (which cannot be represented in UTF-8, even under
1074        the "old" RFC 2279). Instead, it ended up passing a negative length to
1075        pcre_exec().
1076    
1077    31. Add support for GCC's visibility feature to hide internal functions.
1078    
1079    32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
1080        "unknown -C option" after outputting 0 or 1.
1081    
1082    33. There is now support for generating a code coverage report for the test
1083        suite in environments where gcc is the compiler and lcov is installed. This
1084        is mainly for the benefit of the developers.
1085    
1086    34. If PCRE is built with --enable-valgrind, certain memory regions are marked
1087        unaddressable using valgrind annotations, allowing valgrind to detect
1088        invalid memory accesses. This is mainly for the benefit of the developers.
1089    
1090    25. (*UTF) can now be used to start a pattern in any of the three libraries.
1091    
1092    26. Give configure error if --enable-cpp but no C++ compiler found.
1093    
1094    
1095    Version 8.31 06-July-2012
1096    -------------------------
1097    
1098    1.  Fixing a wrong JIT test case and some compiler warnings.
1099    
1100    2.  Removed a bashism from the RunTest script.
1101    
1102    3.  Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
1103        to unsigned type, result still unsigned" that was given by an MS compiler
1104        on encountering the code "-sizeof(xxx)".
1105    
1106    4.  Partial matching support is added to the JIT compiler.
1107    
1108    5.  Fixed several bugs concerned with partial matching of items that consist
1109        of more than one character:
1110    
1111        (a) /^(..)\1/ did not partially match "aba" because checking references was
1112            done on an "all or nothing" basis. This also applied to repeated
1113            references.
1114    
1115        (b) \R did not give a hard partial match if \r was found at the end of the
1116            subject.
1117    
1118        (c) \X did not give a hard partial match after matching one or more
1119            characters at the end of the subject.
1120    
1121        (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
1122            a partial match for the string "\r".
1123    
1124        (e) When newline was set to CRLF, the metacharacter "." did not recognize
1125            a partial match for a CR character at the end of the subject string.
1126    
1127    6.  If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
1128        running pcretest, the text "(JIT)" added to the output whenever JIT is
1129        actually used to run the match.
1130    
1131    7.  Individual JIT compile options can be set in pcretest by following -s+[+]
1132        or /S+[+] with a digit between 1 and 7.
1133    
1134    8.  OP_NOT now supports any UTF character not just single-byte ones.
1135    
1136    9.  (*MARK) control verb is now supported by the JIT compiler.
1137    
1138    10. The command "./RunTest list" lists the available tests without actually
1139        running any of them. (Because I keep forgetting what they all are.)
1140    
1141    11. Add PCRE_INFO_MAXLOOKBEHIND.
1142    
1143    12. Applied a (slightly modified) user-supplied patch that improves performance
1144        when the heap is used for recursion (compiled with --disable-stack-for-
1145        recursion). Instead of malloc and free for each heap frame each time a
1146        logical recursion happens, frames are retained on a chain and re-used where
1147        possible. This sometimes gives as much as 30% improvement.
1148    
1149    13. As documented, (*COMMIT) is now confined to within a recursive subpattern
1150        call.
1151    
1152    14. As documented, (*COMMIT) is now confined to within a positive assertion.
1153    
1154    15. It is now possible to link pcretest with libedit as an alternative to
1155        libreadline.
1156    
1157    16. (*COMMIT) control verb is now supported by the JIT compiler.
1158    
1159    17. The Unicode data tables have been updated to Unicode 6.1.0.
1160    
1161    18. Added --file-list option to pcregrep.
1162    
1163    19. Added binary file support to pcregrep, including the -a, --binary-files,
1164        -I, and --text options.
1165    
1166    20. The madvise function is renamed for posix_madvise for QNX compatibility
1167        reasons. Fixed by Giuseppe D'Angelo.
1168    
1169    21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
1170    
1171    22. Changed the option for creating symbolic links for 16-bit man pages from
1172        -s to -sf so that re-installing does not cause issues.
1173    
1174    23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
1175    
1176    24. Fixed a very old bug in pcretest that caused errors with restarted DFA
1177        matches in certain environments (the workspace was not being correctly
1178        retained). Also added to pcre_dfa_exec() a simple plausibility check on
1179        some of the workspace data at the beginning of a restart.
1180    
1181    25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
1182        was not doing so when it should - probably a typo introduced by SVN 528
1183        (change 8.10/14).
1184    
1185    26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
1186        \w+ when the character tables indicated that \x{c4} was a word character.
1187        There were several related cases, all because the tests for doing a table
1188        lookup were testing for characters less than 127 instead of 255.
1189    
1190    27. If a pattern contains capturing parentheses that are not used in a match,
1191        their slots in the ovector are set to -1. For those that are higher than
1192        any matched groups, this happens at the end of processing. In the case when
1193        there were back references that the ovector was too small to contain
1194        (causing temporary malloc'd memory to be used during matching), and the
1195        highest capturing number was not used, memory off the end of the ovector
1196        was incorrectly being set to -1. (It was using the size of the temporary
1197        memory instead of the true size.)
1198    
1199    28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
1200        ovector size, it uses memory at the end of the block that it has got.
1201    
1202    29. Check for an overlong MARK name and give an error at compile time. The
1203        limit is 255 for the 8-bit library and 65535 for the 16-bit library.
1204    
1205    30. JIT compiler update.
1206    
1207    31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
1208        Rill for the patch.
1209    
1210    32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
1211    
1212    33. Variable renamings in the PCRE-JIT compiler. No functionality change.
1213    
1214    34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
1215        SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
1216        was enabled.
1217    
1218    35. Improve JIT code generation for greedy plus quantifier.
1219    
1220    36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
1221        1 to "aa" instead of to an empty string. The bug affected repeated groups
1222        that could potentially match an empty string.
1223    
1224    37. Optimizing single character iterators in JIT.
1225    
1226    38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
1227        the same checks as \x{...} characters in non-JavaScript mode. Specifically,
1228        codepoints that are too big for the mode are faulted, and in a UTF mode,
1229        disallowed codepoints are also faulted.
1230    
1231    39. If PCRE was compiled with UTF support, in three places in the DFA
1232        matcher there was code that should only have been obeyed in UTF mode, but
1233        was being obeyed unconditionally. In 8-bit mode this could cause incorrect
1234        processing when bytes with values greater than 127 were present. In 16-bit
1235        mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
1236        both cases the values are those that cannot be the first data item in a UTF
1237        character. The three items that might have provoked this were recursions,
1238        possessively repeated groups, and atomic groups.
1239    
1240    40. Ensure that libpcre is explicitly listed in the link commands for pcretest
1241        and pcregrep, because some OS require shared objects to be explicitly
1242        passed to ld, causing the link step to fail if they are not.
1243    
1244    41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
1245        mode, patterns that started with \h* or \R* might be incorrectly matched.
1246    
1247    
1248    Version 8.30 04-February-2012
1249    -----------------------------
1250    
1251    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
1252        name is defined in ctype.h.
1253    
1254    2.  Fixed a bug in fixed-length calculation for lookbehinds that would show up
1255        only in quite long subpatterns.
1256    
1257    3.  Removed the function pcre_info(), which has been obsolete and deprecated
1258        since it was replaced by pcre_fullinfo() in February 2000.
1259    
1260    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
1261        match a (*MARK), and the match failed at the start of the subject, a
1262        reference to memory before the start of the subject could occur. This bug
1263        was introduced by fix 17 of release 8.21.
1264    
1265    5.  A reference to an unset group with zero minimum repetition was giving
1266        totally wrong answers (in non-JavaScript-compatibility mode). For example,
1267        /(another)?(\1?)test/ matched against "hello world test". This bug was
1268        introduced in release 8.13.
1269    
1270    6.  Add support for 16-bit character strings (a large amount of work involving
1271        many changes and refactorings).
1272    
1273    7.  RunGrepTest failed on msys because \r\n was replaced by whitespace when the
1274        command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
1275        from a file.
1276    
1277    8.  Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
1278        rounding is not applied in this particular case).
1279    
1280    9.  The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
1281        if they appear, or are escaped, in patterns.
1282    
1283    10. Get rid of a number of -Wunused-but-set-variable warnings.
1284    
1285    11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
1286        "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
1287        Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
1288        also returns the mark "x". This bug applied to capturing parentheses,
1289        non-capturing parentheses, and atomic parentheses. It also applied to some
1290        assertions.
1291    
1292    12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
1293        information out of configure.ac instead of relying on pcre.h.generic, which
1294        is not stored in the repository.
1295    
1296    13. Applied Dmitry V. Levin's patch for a more portable method for linking with
1297        -lreadline.
1298    
1299    14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
1300    
1301    15. Applied Graycode's patch to put the top-level frame on the stack rather
1302        than the heap when not using the stack for recursion. This gives a
1303        performance improvement in many cases when recursion is not deep.
1304    
1305    16. Experimental code added to "pcretest -C" to output the stack frame size.
1306    
1307    
1308    Version 8.21 12-Dec-2011
1309    ------------------------
1310    
1311  1.  Updating the JIT compiler.  1.  Updating the JIT compiler.
1312    
1313    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
1314        are added as well.
1315    
1316    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
1317        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
1318        calling _pcre_jit_exec. Some extra comments are added.
1319    
1320    4.  (*MARK) settings inside atomic groups that do not contain any capturing
1321        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
1322        was introduced by change 18 for 8.20.
1323    
1324    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
1325        ECMA-262 standard.
1326    
1327    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
1328        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
1329        This bug was probably introduced by change 9 of 8.13.
1330    
1331    7.  While fixing 6 above, I noticed that a number of other items were being
1332        incorrectly rejected as "not fixed length". This arose partly because newer
1333        opcodes had not been added to the fixed-length checking code. I have (a)
1334        corrected the bug and added tests for these items, and (b) arranged for an
1335        error to occur if an unknown opcode is encountered while checking for fixed
1336        length instead of just assuming "not fixed length". The items that were
1337        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
1338        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
1339        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
1340    
1341    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
1342        being incorrectly compiled and would have given unpredicatble results.
1343    
1344    9.  A possessively repeated subpattern with minimum repeat count greater than
1345        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
1346        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
1347        the first (A) could occur when it should not.
1348    
1349    10. Add a cast and remove a redundant test from the code.
1350    
1351    11. JIT should use pcre_malloc/pcre_free for allocation.
1352    
1353    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
1354        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
1355        is anything other than /usr, -L is still shown).
1356    
1357    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
1358    
1359    14. Perl does not support \N without a following name in a [] class; PCRE now
1360        also gives an error.
1361    
1362    15. If a forward reference was repeated with an upper limit of around 2000,
1363        it caused the error "internal error: overran compiling workspace". The
1364        maximum number of forward references (including repeats) was limited by the
1365        internal workspace, and dependent on the LINK_SIZE. The code has been
1366        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
1367        the default depends on LINK_SIZE. There is a new upper limit (for safety)
1368        of around 200,000 forward references. While doing this, I also speeded up
1369        the filling in of repeated forward references.
1370    
1371    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
1372        incorrectly expecting the subject to contain another "a" after the start.
1373    
1374    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
1375        in the match, the SKIP should be ignored. This was not happening; instead
1376        the SKIP was being treated as NOMATCH. For patterns such as
1377        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
1378        tested.
1379    
1380    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
1381        now much more compatible with Perl, in particular in cases where the result
1382        is a non-match for a non-anchored pattern. For example, if
1383        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
1384        "m", where previously it did not return a name. A side effect of this
1385        change is that for partial matches, the last encountered mark name is
1386        returned, as for non matches. A number of tests that were previously not
1387        Perl-compatible have been moved into the Perl-compatible test files. The
1388        refactoring has had the pleasing side effect of removing one argument from
1389        the match() function, thus reducing its stack requirements.
1390    
1391    19. If the /S+ option was used in pcretest to study a pattern using JIT,
1392        subsequent uses of /S (without +) incorrectly behaved like /S+.
1393    
1394    21. Retrieve executable code size support for the JIT compiler and fixing
1395        some warnings.
1396    
1397    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
1398        not work when the shorter character appeared right at the end of the
1399        subject string.
1400    
1401    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
1402        systems.
1403    
1404    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
1405        output it when the /M option is used in pcretest.
1406    
1407    25. The CheckMan script was not being included in the distribution. Also, added
1408        an explicit "perl" to run Perl scripts from the PrepareRelease script
1409        because this is reportedly needed in Windows.
1410    
1411    26. If study data was being save in a file and studying had not found a set of
1412        "starts with" bytes for the pattern, the data written to the file (though
1413        never used) was taken from uninitialized memory and so caused valgrind to
1414        complain.
1415    
1416    27. Updated RunTest.bat as provided by Sheri Pierce.
1417    
1418    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
1419    
1420    29. Computation of memory usage for the table of capturing group names was
1421        giving an unnecessarily large value.
1422    
1423    
1424  Version 8.20 21-Oct-2011  Version 8.20 21-Oct-2011
1425  ------------------------  ------------------------
# Line 1021  Version 7.9 11-Apr-09 Line 2435  Version 7.9 11-Apr-09
2435  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
2436      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
2437      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this      locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
2438      seems to be how GNU grep behaves.      seems to be how GNU grep behaves. [But see later change 40 for release
2439        8.33.]
2440    
2441  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
2442      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 1264  Version 7.7 07-May-08 Line 2679  Version 7.7 07-May-08
2679      containing () gave an internal compiling error instead of "reference to      containing () gave an internal compiling error instead of "reference to
2680      non-existent subpattern". Fortunately, when the pattern did exist, the      non-existent subpattern". Fortunately, when the pattern did exist, the
2681      compiled code was correct. (When scanning forwards to check for the      compiled code was correct. (When scanning forwards to check for the
2682      existencd of the subpattern, it was treating the data ']' as terminating      existence of the subpattern, it was treating the data ']' as terminating
2683      the class, so got the count wrong. When actually compiling, the reference      the class, so got the count wrong. When actually compiling, the reference
2684      was subsequently set up correctly.)      was subsequently set up correctly.)
2685    

Legend:
Removed from v.740  
changed lines
  Added in v.1604

  ViewVC Help
Powered by ViewVC 1.1.5