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

Diff of /code/trunk/ChangeLog

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

revision 654 by ph10, Tue Aug 2 11:00:40 2011 UTC revision 836 by ph10, Wed Dec 28 17:16:11 2011 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4  Version 8.13 02-Aug-2011  Version 8.30
5    ------------
6    
7    1.  Renamed "isnumber" as "is_a_number" because in some Mac environments this
8        name is defined in ctype.h.
9    
10    2.  Fixed a bug in the code for calculating the fixed length of lookbehind
11        assertions.
12    
13    3.  Removed the function pcre_info(), which has been obsolete and deprecated
14        since it was replaced by pcre_fullinfo() in February 2000.
15    
16    4.  For a non-anchored pattern, if (*SKIP) was given with a name that did not
17        match a (*MARK), and the match failed at the start of the subject, a
18        reference to memory before the start of the subject could occur. This bug
19        was introduced by fix 17 of release 8.21.
20    
21    5.  A reference to an unset group with zero minimum repetition was giving
22        totally wrong answers (in non-JavaScript-compatibility mode). For example,
23        /(another)?(\1?)test/ matched against "hello world test". This bug was
24        introduced in release 8.13.
25    
26    6.  Add support for 16-bit character strings (a large amount of work involving
27        many changes and refactorings).
28    
29    
30    Version 8.21 12-Dec-2011
31    ------------------------
32    
33    1.  Updating the JIT compiler.
34    
35    2.  JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
36        are added as well.
37    
38    3.  Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
39        PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
40        calling _pcre_jit_exec. Some extra comments are added.
41    
42    4.  (*MARK) settings inside atomic groups that do not contain any capturing
43        parentheses, for example, (?>a(*:m)), were not being passed out. This bug
44        was introduced by change 18 for 8.20.
45    
46    5.  Supporting of \x, \U and \u in JavaScript compatibility mode based on the
47        ECMA-262 standard.
48    
49    6.  Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
50        erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
51        This bug was probably introduced by change 9 of 8.13.
52    
53    7.  While fixing 6 above, I noticed that a number of other items were being
54        incorrectly rejected as "not fixed length". This arose partly because newer
55        opcodes had not been added to the fixed-length checking code. I have (a)
56        corrected the bug and added tests for these items, and (b) arranged for an
57        error to occur if an unknown opcode is encountered while checking for fixed
58        length instead of just assuming "not fixed length". The items that were
59        rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
60        (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
61        repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
62    
63    8.  A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
64        being incorrectly compiled and would have given unpredicatble results.
65    
66    9.  A possessively repeated subpattern with minimum repeat count greater than
67        one behaved incorrectly. For example, (A){2,}+ behaved as if it was
68        (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
69        the first (A) could occur when it should not.
70    
71    10. Add a cast and remove a redundant test from the code.
72    
73    11. JIT should use pcre_malloc/pcre_free for allocation.
74    
75    12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
76        best practice nowadays, and helps with cross-compiling. (If the exec_prefix
77        is anything other than /usr, -L is still shown).
78    
79    13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
80    
81    14. Perl does not support \N without a following name in a [] class; PCRE now
82        also gives an error.
83    
84    15. If a forward reference was repeated with an upper limit of around 2000,
85        it caused the error "internal error: overran compiling workspace". The
86        maximum number of forward references (including repeats) was limited by the
87        internal workspace, and dependent on the LINK_SIZE. The code has been
88        rewritten so that the workspace expands (via pcre_malloc) if necessary, and
89        the default depends on LINK_SIZE. There is a new upper limit (for safety)
90        of around 200,000 forward references. While doing this, I also speeded up
91        the filling in of repeated forward references.
92    
93    16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
94        incorrectly expecting the subject to contain another "a" after the start.
95    
96    17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
97        in the match, the SKIP should be ignored. This was not happening; instead
98        the SKIP was being treated as NOMATCH. For patterns such as
99        /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
100        tested.
101    
102    18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
103        now much more compatible with Perl, in particular in cases where the result
104        is a non-match for a non-anchored pattern. For example, if
105        /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
106        "m", where previously it did not return a name. A side effect of this
107        change is that for partial matches, the last encountered mark name is
108        returned, as for non matches. A number of tests that were previously not
109        Perl-compatible have been moved into the Perl-compatible test files. The
110        refactoring has had the pleasing side effect of removing one argument from
111        the match() function, thus reducing its stack requirements.
112    
113    19. If the /S+ option was used in pcretest to study a pattern using JIT,
114        subsequent uses of /S (without +) incorrectly behaved like /S+.
115    
116    21. Retrieve executable code size support for the JIT compiler and fixing
117        some warnings.
118    
119    22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
120        not work when the shorter character appeared right at the end of the
121        subject string.
122    
123    23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
124        systems.
125    
126    24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
127        output it when the /M option is used in pcretest.
128    
129    25. The CheckMan script was not being included in the distribution. Also, added
130        an explicit "perl" to run Perl scripts from the PrepareRelease script
131        because this is reportedly needed in Windows.
132    
133    26. If study data was being save in a file and studying had not found a set of
134        "starts with" bytes for the pattern, the data written to the file (though
135        never used) was taken from uninitialized memory and so caused valgrind to
136        complain.
137    
138    27. Updated RunTest.bat as provided by Sheri Pierce.
139    
140    28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
141    
142    29. Computation of memory usage for the table of capturing group names was
143        giving an unnecessarily large value.
144    
145    
146    Version 8.20 21-Oct-2011
147    ------------------------
148    
149    1.  Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
150        a POSIX class. After further experiments with Perl, which convinced me that
151        Perl has bugs and confusions, a closing square bracket is no longer allowed
152        in a POSIX name. This bug also affected patterns with classes that started
153        with full stops.
154    
155    2.  If a pattern such as /(a)b|ac/ is matched against "ac", there is no
156        captured substring, but while checking the failing first alternative,
157        substring 1 is temporarily captured. If the output vector supplied to
158        pcre_exec() was not big enough for this capture, the yield of the function
159        was still zero ("insufficient space for captured substrings"). This cannot
160        be totally fixed without adding another stack variable, which seems a lot
161        of expense for a edge case. However, I have improved the situation in cases
162        such as /(a)(b)x|abc/ matched against "abc", where the return code
163        indicates that fewer than the maximum number of slots in the ovector have
164        been set.
165    
166    3.  Related to (2) above: when there are more back references in a pattern than
167        slots in the output vector, pcre_exec() uses temporary memory during
168        matching, and copies in the captures as far as possible afterwards. It was
169        using the entire output vector, but this conflicts with the specification
170        that only 2/3 is used for passing back captured substrings. Now it uses
171        only the first 2/3, for compatibility. This is, of course, another edge
172        case.
173    
174    4.  Zoltan Herczeg's just-in-time compiler support has been integrated into the
175        main code base, and can be used by building with --enable-jit. When this is
176        done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
177        runtime --no-jit option is given.
178    
179    5.  When the number of matches in a pcre_dfa_exec() run exactly filled the
180        ovector, the return from the function was zero, implying that there were
181        other matches that did not fit. The correct "exactly full" value is now
182        returned.
183    
184    6.  If a subpattern that was called recursively or as a subroutine contained
185        (*PRUNE) or any other control that caused it to give a non-standard return,
186        invalid errors such as "Error -26 (nested recursion at the same subject
187        position)" or even infinite loops could occur.
188    
189    7.  If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
190        computing the minimum length on reaching *ACCEPT, and so ended up with the
191        wrong value of 1 rather than 0. Further investigation indicates that
192        computing a minimum subject length in the presence of *ACCEPT is difficult
193        (think back references, subroutine calls), and so I have changed the code
194        so that no minimum is registered for a pattern that contains *ACCEPT.
195    
196    8.  If (*THEN) was present in the first (true) branch of a conditional group,
197        it was not handled as intended. [But see 16 below.]
198    
199    9.  Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
200        Sheri Pierce.
201    
202    10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
203        the first byte in a match must be "a".
204    
205    11. Change 17 for 8.13 increased the recursion depth for patterns like
206        /a(?:.)*?a/ drastically. I've improved things by remembering whether a
207        pattern contains any instances of (*THEN). If it does not, the old
208        optimizations are restored. It would be nice to do this on a per-group
209        basis, but at the moment that is not feasible.
210    
211    12. In some environments, the output of pcretest -C is CRLF terminated. This
212        broke RunTest's code that checks for the link size. A single white space
213        character after the value is now allowed for.
214    
215    13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
216        For "fr", it uses the Windows-specific input and output files.
217    
218    14. If (*THEN) appeared in a group that was called recursively or as a
219        subroutine, it did not work as intended. [But see next item.]
220    
221    15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
222        pattern fragments (but not containing any | characters). If A and B are
223        matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
224        was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
225        D. In other words, Perl considers parentheses that do not contain any |
226        characters to be part of a surrounding alternative, whereas PCRE was
227        treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
228        differently. PCRE now behaves in the same way as Perl, except in the case
229        of subroutine/recursion calls such as (?1) which have in any case always
230        been different (but PCRE had them first :-).
231    
232    16. Related to 15 above: Perl does not treat the | in a conditional group as
233        creating alternatives. Such a group is treated in the same way as an
234        ordinary group without any | characters when processing (*THEN). PCRE has
235        been changed to match Perl's behaviour.
236    
237    17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
238        RunGrepTest script failed.
239    
240    18. Change 22 for version 13 caused atomic groups to use more stack. This is
241        inevitable for groups that contain captures, but it can lead to a lot of
242        stack use in large patterns. The old behaviour has been restored for atomic
243        groups that do not contain any capturing parentheses.
244    
245    19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
246        suppress the check for a minimum subject length at run time. (If it was
247        given to pcre_exec() or pcre_dfa_exec() it did work.)
248    
249    20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
250        fail to work when decoding hex characters in data strings in EBCDIC
251        environments.
252    
253    21. It appears that in at least one Mac OS environment, the isxdigit() function
254        is implemented as a macro that evaluates to its argument more than once,
255        contravening the C 90 Standard (I haven't checked a later standard). There
256        was an instance in pcretest which caused it to go wrong when processing
257        \x{...} escapes in subject strings. The has been rewritten to avoid using
258        things like p++ in the argument of isxdigit().
259    
260    
261    Version 8.13 16-Aug-2011
262  ------------------------  ------------------------
263    
264  1.  The Unicode data tables have been updated to Unicode 6.0.0.  1.  The Unicode data tables have been updated to Unicode 6.0.0.
# Line 98  Version 8.13 02-Aug-2011 Line 355  Version 8.13 02-Aug-2011
355      tail recursion to cut down on stack usage. Unfortunately, now that there is      tail recursion to cut down on stack usage. Unfortunately, now that there is
356      the possibility of (*THEN) occurring in these branches, tail recursion is      the possibility of (*THEN) occurring in these branches, tail recursion is
357      no longer possible because the return has to be checked for (*THEN). These      no longer possible because the return has to be checked for (*THEN). These
358      two optimizations have therefore been removed.      two optimizations have therefore been removed. [But see 8.20/11 above.]
359    
360  18. If a pattern containing \R was studied, it was assumed that \R always  18. If a pattern containing \R was studied, it was assumed that \R always
361      matched two bytes, thus causing the minimum subject length to be      matched two bytes, thus causing the minimum subject length to be
# Line 189  Version 8.13 02-Aug-2011 Line 446  Version 8.13 02-Aug-2011
446      For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,      For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
447      unescaped square brackets may also appear as part of class names. For      unescaped square brackets may also appear as part of class names. For
448      example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves      example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
449      more like Perl.      more like Perl. (But see 8.20/1 above.)
450    
451  38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this  38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
452      was because it thought it was \N{name}, which is not supported).      was because it thought it was \N{name}, which is not supported).
# Line 224  Version 8.13 02-Aug-2011 Line 481  Version 8.13 02-Aug-2011
481      (a) The default value of the buffer size parameter has been increased from      (a) The default value of the buffer size parameter has been increased from
482          8K to 20K. (The actual buffer used is three times this size.)          8K to 20K. (The actual buffer used is three times this size.)
483    
484      (b) The default can be changed by ./configure --with-pcregrep-bufsiz when      (b) The default can be changed by ./configure --with-pcregrep-bufsize when
485          PCRE is built.          PCRE is built.
486    
487      (c) A --buffer-size=n option has been added to pcregrep, to allow the size      (c) A --buffer-size=n option has been added to pcregrep, to allow the size
# Line 246  Version 8.13 02-Aug-2011 Line 503  Version 8.13 02-Aug-2011
503      complete match instead of a partial match. This bug was dependent on both      complete match instead of a partial match. This bug was dependent on both
504      the PCRE_UTF8 and PCRE_DOTALL options being set.      the PCRE_UTF8 and PCRE_DOTALL options being set.
505    
506    48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
507        starting byte set, because \b was not being ignored.
508    
509    
510  Version 8.12 15-Jan-2011  Version 8.12 15-Jan-2011
511  ------------------------  ------------------------

Legend:
Removed from v.654  
changed lines
  Added in v.836

  ViewVC Help
Powered by ViewVC 1.1.5