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authorGravatar Aaron Gyes <me@aaron.gy>2016-04-14 22:21:36 -0700
committerGravatar David Adam <zanchey@ucc.gu.uwa.edu.au>2016-04-19 11:49:12 +0800
commit0fd3f5c0ddf830162b66067e536bdbf0975523e5 (patch)
treea3ee179caef36f2a62452b9325c0ce6b47c90148 /pcre2-10.21/ChangeLog
parente7599fd18cba9fde4ed19aae70c10e622d7d2e0e (diff)
Update to pcre2 10.21
Point build tools at 10.21
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+Change Log for PCRE2
+--------------------
+
+Version 10.21 12-January-2016
+-----------------------------
+
+1. Improve matching speed of patterns starting with + or * in JIT.
+
+2. Use memchr() to find the first character in an unanchored match in 8-bit
+mode in the interpreter. This gives a significant speed improvement.
+
+3. Removed a redundant copy of the opcode_possessify table in the
+pcre2_auto_possessify.c source.
+
+4. Fix typos in dftables.c for z/OS.
+
+5. Change 36 for 10.20 broke the handling of [[:>:]] and [[:<:]] in that
+processing them could involve a buffer overflow if the following character was
+an opening parenthesis.
+
+6. Change 36 for 10.20 also introduced a bug in processing this pattern:
+/((?x)(*:0))#(?'/. Specifically: if a setting of (?x) was followed by a (*MARK)
+setting (which (*:0) is), then (?x) did not get unset at the end of its group
+during the scan for named groups, and hence the external # was incorrectly
+treated as a comment and the invalid (?' at the end of the pattern was not
+diagnosed. This caused a buffer overflow during the real compile. This bug was
+discovered by Karl Skomski with the LLVM fuzzer.
+
+7. Moved the pcre2_find_bracket() function from src/pcre2_compile.c into its
+own source module to avoid a circular dependency between src/pcre2_compile.c
+and src/pcre2_study.c
+
+8. A callout with a string argument containing an opening square bracket, for
+example /(?C$[$)(?<]/, was incorrectly processed and could provoke a buffer
+overflow. This bug was discovered by Karl Skomski with the LLVM fuzzer.
+
+9. The handling of callouts during the pre-pass for named group identification
+has been tightened up.
+
+10. The quantifier {1} can be ignored, whether greedy, non-greedy, or
+possessive. This is a very minor optimization.
+
+11. A possessively repeated conditional group that could match an empty string,
+for example, /(?(R))*+/, was incorrectly compiled.
+
+12. The Unicode tables have been updated to Unicode 8.0.0 (thanks to Christian
+Persch).
+
+13. An empty comment (?#) in a pattern was incorrectly processed and could
+provoke a buffer overflow. This bug was discovered by Karl Skomski with the
+LLVM fuzzer.
+
+14. Fix infinite recursion in the JIT compiler when certain patterns such as
+/(?:|a|){100}x/ are analysed.
+
+15. Some patterns with character classes involving [: and \\ were incorrectly
+compiled and could cause reading from uninitialized memory or an incorrect
+error diagnosis. Examples are: /[[:\\](?<[::]/ and /[[:\\](?'abc')[a:]. The
+first of these bugs was discovered by Karl Skomski with the LLVM fuzzer.
+
+16. Pathological patterns containing many nested occurrences of [: caused
+pcre2_compile() to run for a very long time. This bug was found by the LLVM
+fuzzer.
+
+17. A missing closing parenthesis for a callout with a string argument was not
+being diagnosed, possibly leading to a buffer overflow. This bug was found by
+the LLVM fuzzer.
+
+18. A conditional group with only one branch has an implicit empty alternative
+branch and must therefore be treated as potentially matching an empty string.
+
+19. If (?R was followed by - or + incorrect behaviour happened instead of a
+diagnostic. This bug was discovered by Karl Skomski with the LLVM fuzzer.
+
+20. Another bug that was introduced by change 36 for 10.20: conditional groups
+whose condition was an assertion preceded by an explicit callout with a string
+argument might be incorrectly processed, especially if the string contained \Q.
+This bug was discovered by Karl Skomski with the LLVM fuzzer.
+
+21. Compiling PCRE2 with the sanitize options of clang showed up a number of
+very pedantic coding infelicities and a buffer overflow while checking a UTF-8
+string if the final multi-byte UTF-8 character was truncated.
+
+22. For Perl compatibility in EBCDIC environments, ranges such as a-z in a
+class, where both values are literal letters in the same case, omit the
+non-letter EBCDIC code points within the range.
+
+23. Finding the minimum matching length of complex patterns with back
+references and/or recursions can take a long time. There is now a cut-off that
+gives up trying to find a minimum length when things get too complex.
+
+24. An optimization has been added that speeds up finding the minimum matching
+length for patterns containing repeated capturing groups or recursions.
+
+25. If a pattern contained a back reference to a group whose number was
+duplicated as a result of appearing in a (?|...) group, the computation of the
+minimum matching length gave a wrong result, which could cause incorrect "no
+match" errors. For such patterns, a minimum matching length cannot at present
+be computed.
+
+26. Added a check for integer overflow in conditions (?(<digits>) and
+(?(R<digits>). This omission was discovered by Karl Skomski with the LLVM
+fuzzer.
+
+27. Fixed an issue when \p{Any} inside an xclass did not read the current
+character.
+
+28. If pcre2grep was given the -q option with -c or -l, or when handling a
+binary file, it incorrectly wrote output to stdout.
+
+29. The JIT compiler did not restore the control verb head in case of *THEN
+control verbs. This issue was found by Karl Skomski with a custom LLVM fuzzer.
+
+30. The way recursive references such as (?3) are compiled has been re-written
+because the old way was the cause of many issues. Now, conversion of the group
+number into a pattern offset does not happen until the pattern has been
+completely compiled. This does mean that detection of all infinitely looping
+recursions is postponed till match time. In the past, some easy ones were
+detected at compile time. This re-writing was done in response to yet another
+bug found by the LLVM fuzzer.
+
+31. A test for a back reference to a non-existent group was missing for items
+such as \987. This caused incorrect code to be compiled. This issue was found
+by Karl Skomski with a custom LLVM fuzzer.
+
+32. Error messages for syntax errors following \g and \k were giving inaccurate
+offsets in the pattern.
+
+33. Improve the performance of starting single character repetitions in JIT.
+
+34. (*LIMIT_MATCH=) now gives an error instead of setting the value to 0.
+
+35. Error messages for syntax errors in *LIMIT_MATCH and *LIMIT_RECURSION now
+give the right offset instead of zero.
+
+36. The JIT compiler should not check repeats after a {0,1} repeat byte code.
+This issue was found by Karl Skomski with a custom LLVM fuzzer.
+
+37. The JIT compiler should restore the control chain for empty possessive
+repeats. This issue was found by Karl Skomski with a custom LLVM fuzzer.
+
+38. A bug which was introduced by the single character repetition optimization
+was fixed.
+
+39. Match limit check added to recursion. This issue was found by Karl Skomski
+with a custom LLVM fuzzer.
+
+40. Arrange for the UTF check in pcre2_match() and pcre2_dfa_match() to look
+only at the part of the subject that is relevant when the starting offset is
+non-zero.
+
+41. Improve first character match in JIT with SSE2 on x86.
+
+42. Fix two assertion fails in JIT. These issues were found by Karl Skomski
+with a custom LLVM fuzzer.
+
+43. Correct the setting of CMAKE_C_FLAGS in CMakeLists.txt (patch from Roy Ivy
+III).
+
+44. Fix bug in RunTest.bat for new test 14, and adjust the script for the added
+test (there are now 20 in total).
+
+45. Fixed a corner case of range optimization in JIT.
+
+46. Add the ${*MARK} facility to pcre2_substitute().
+
+47. Modifier lists in pcre2test were splitting at spaces without the required
+commas.
+
+48. Implemented PCRE2_ALT_VERBNAMES.
+
+49. Fixed two issues in JIT. These were found by Karl Skomski with a custom
+LLVM fuzzer.
+
+50. The pcre2test program has been extended by adding the #newline_default
+command. This has made it possible to run the standard tests when PCRE2 is
+compiled with either CR or CRLF as the default newline convention. As part of
+this work, the new command was added to several test files and the testing
+scripts were modified. The pcre2grep tests can now also be run when there is no
+LF in the default newline convention.
+
+51. The RunTest script has been modified so that, when JIT is used and valgrind
+is specified, a valgrind suppressions file is set up to ignore "Invalid read of
+size 16" errors because these are false positives when the hardware supports
+the SSE2 instruction set.
+
+52. It is now possible to have comment lines amid the subject strings in
+pcre2test (and perltest.sh) input.
+
+53. Implemented PCRE2_USE_OFFSET_LIMIT and pcre2_set_offset_limit().
+
+54. Add the null_context modifier to pcre2test so that calling pcre2_compile()
+and the matching functions with NULL contexts can be tested.
+
+55. Implemented PCRE2_SUBSTITUTE_EXTENDED.
+
+56. In a character class such as [\W\p{Any}] where both a negative-type escape
+("not a word character") and a property escape were present, the property
+escape was being ignored.
+
+57. Fixed integer overflow for patterns whose minimum matching length is very,
+very large.
+
+58. Implemented --never-backslash-C.
+
+59. Change 55 above introduced a bug by which certain patterns provoked the
+erroneous error "\ at end of pattern".
+
+60. The special sequences [[:<:]] and [[:>:]] gave rise to incorrect compiling
+errors or other strange effects if compiled in UCP mode. Found with libFuzzer
+and AddressSanitizer.
+
+61. Whitespace at the end of a pcre2test pattern line caused a spurious error
+message if there were only single-character modifiers. It should be ignored.
+
+62. The use of PCRE2_NO_AUTO_CAPTURE could cause incorrect compilation results
+or segmentation errors for some patterns. Found with libFuzzer and
+AddressSanitizer.
+
+63. Very long names in (*MARK) or (*THEN) etc. items could provoke a buffer
+overflow.
+
+64. Improve error message for overly-complicated patterns.
+
+65. Implemented an optional replication feature for patterns in pcre2test, to
+make it easier to test long repetitive patterns. The tests for 63 above are
+converted to use the new feature.
+
+66. In the POSIX wrapper, if regerror() was given too small a buffer, it could
+misbehave.
+
+67. In pcre2_substitute() in UTF mode, the UTF validity check on the
+replacement string was happening before the length setting when the replacement
+string was zero-terminated.
+
+68. In pcre2_substitute() in UTF mode, PCRE2_NO_UTF_CHECK can be set for the
+second and subsequent calls to pcre2_match().
+
+69. There was no check for integer overflow for a replacement group number in
+pcre2_substitute(). An added check for a number greater than the largest group
+number in the pattern means this is not now needed.
+
+70. The PCRE2-specific VERSION condition didn't work correctly if only one
+digit was given after the decimal point, or if more than two digits were given.
+It now works with one or two digits, and gives a compile time error if more are
+given.
+
+71. In pcre2_substitute() there was the possibility of reading one code unit
+beyond the end of the replacement string.
+
+72. The code for checking a subject's UTF-32 validity for a pattern with a
+lookbehind involved an out-of-bounds pointer, which could potentially cause
+trouble in some environments.
+
+73. The maximum lookbehind length was incorrectly calculated for patterns such
+as /(?<=(a)(?-1))x/ which have a recursion within a backreference.
+
+74. Give an error if a lookbehind assertion is longer than 65535 code units.
+
+75. Give an error in pcre2_substitute() if a match ends before it starts (as a
+result of the use of \K).
+
+76. Check the length of subpattern names and the names in (*MARK:xx) etc.
+dynamically to avoid the possibility of integer overflow.
+
+77. Implement pcre2_set_max_pattern_length() so that programs can restrict the
+size of patterns that they are prepared to handle.
+
+78. (*NO_AUTO_POSSESS) was not working.
+
+79. Adding group information caching improves the speed of compiling when
+checking whether a group has a fixed length and/or could match an empty string,
+especially when recursion or subroutine calls are involved. However, this
+cannot be used when (?| is present in the pattern because the same number may
+be used for groups of different sizes. To catch runaway patterns in this
+situation, counts have been introduced to the functions that scan for empty
+branches or compute fixed lengths.
+
+80. Allow for the possibility of the size of the nest_save structure not being
+a factor of the size of the compiling workspace (it currently is).
+
+81. Check for integer overflow in minimum length calculation and cap it at
+65535.
+
+82. Small optimizations in code for finding the minimum matching length.
+
+83. Lock out configuring for EBCDIC with non-8-bit libraries.
+
+84. Test for error code <= 0 in regerror().
+
+85. Check for too many replacements (more than INT_MAX) in pcre2_substitute().
+
+86. Avoid the possibility of computing with an out-of-bounds pointer (though
+not dereferencing it) while handling lookbehind assertions.
+
+87. Failure to get memory for the match data in regcomp() is now given as a
+regcomp() error instead of waiting for regexec() to pick it up.
+
+88. In pcre2_substitute(), ensure that CRLF is not split when it is a valid
+newline sequence.
+
+89. Paranoid check in regcomp() for bad error code from pcre2_compile().
+
+90. Run test 8 (internal offsets and code sizes) for link sizes 3 and 4 as well
+as for link size 2.
+
+91. Document that JIT has a limit on pattern size, and give more information
+about JIT compile failures in pcre2test.
+
+92. Implement PCRE2_INFO_HASBACKSLASHC.
+
+93. Re-arrange valgrind support code in pcre2test to avoid spurious reports
+with JIT (possibly caused by SSE2?).
+
+94. Support offset_limit in JIT.
+
+95. A sequence such as [[:punct:]b] that is, a POSIX character class followed
+by a single ASCII character in a class item, was incorrectly compiled in UCP
+mode. The POSIX class got lost, but only if the single character followed it.
+
+96. [:punct:] in UCP mode was matching some characters in the range 128-255
+that should not have been matched.
+
+97. If [:^ascii:] or [:^xdigit:] are present in a non-negated class, all
+characters with code points greater than 255 are in the class. When a Unicode
+property was also in the class (if PCRE2_UCP is set, escapes such as \w are
+turned into Unicode properties), wide characters were not correctly handled,
+and could fail to match.
+
+98. In pcre2test, make the "startoffset" modifier a synonym of "offset",
+because it sets the "startoffset" parameter for pcre2_match().
+
+99. If PCRE2_AUTO_CALLOUT was set on a pattern that had a (?# comment between
+an item and its qualifier (for example, A(?#comment)?B) pcre2_compile()
+misbehaved. This bug was found by the LLVM fuzzer.
+
+100. The error for an invalid UTF pattern string always gave the code unit
+offset as zero instead of where the invalidity was found.
+
+101. Further to 97 above, negated classes such as [^[:^ascii:]\d] were also not
+working correctly in UCP mode.
+
+102. Similar to 99 above, if an isolated \E was present between an item and its
+qualifier when PCRE2_AUTO_CALLOUT was set, pcre2_compile() misbehaved. This bug
+was found by the LLVM fuzzer.
+
+103. The POSIX wrapper function regexec() crashed if the option REG_STARTEND
+was set when the pmatch argument was NULL. It now returns REG_INVARG.
+
+104. Allow for up to 32-bit numbers in the ordin() function in pcre2grep.
+
+105. An empty \Q\E sequence between an item and its qualifier caused
+pcre2_compile() to misbehave when auto callouts were enabled. This bug
+was found by the LLVM fuzzer.
+
+106. If both PCRE2_ALT_VERBNAMES and PCRE2_EXTENDED were set, and a (*MARK) or
+other verb "name" ended with whitespace immediately before the closing
+parenthesis, pcre2_compile() misbehaved. Example: /(*:abc )/, but only when
+both those options were set.
+
+107. In a number of places pcre2_compile() was not handling NULL characters
+correctly, and pcre2test with the "bincode" modifier was not always correctly
+displaying fields containing NULLS:
+
+ (a) Within /x extended #-comments
+ (b) Within the "name" part of (*MARK) and other *verbs
+ (c) Within the text argument of a callout
+
+108. If a pattern that was compiled with PCRE2_EXTENDED started with white
+space or a #-type comment that was followed by (?-x), which turns off
+PCRE2_EXTENDED, and there was no subsequent (?x) to turn it on again,
+pcre2_compile() assumed that (?-x) applied to the whole pattern and
+consequently mis-compiled it. This bug was found by the LLVM fuzzer. The fix
+for this bug means that a setting of any of the (?imsxU) options at the start
+of a pattern is no longer transferred to the options that are returned by
+PCRE2_INFO_ALLOPTIONS. In fact, this was an anachronism that should have
+changed when the effects of those options were all moved to compile time.
+
+109. An escaped closing parenthesis in the "name" part of a (*verb) when
+PCRE2_ALT_VERBNAMES was set caused pcre2_compile() to malfunction. This bug
+was found by the LLVM fuzzer.
+
+110. Implemented PCRE2_SUBSTITUTE_UNSET_EMPTY, and updated pcre2test to make it
+possible to test it.
+
+111. "Harden" pcre2test against ridiculously large values in modifiers and
+command line arguments.
+
+112. Implemented PCRE2_SUBSTITUTE_UNKNOWN_UNSET and PCRE2_SUBSTITUTE_OVERFLOW_
+LENGTH.
+
+113. Fix printing of *MARK names that contain binary zeroes in pcre2test.
+
+
+Version 10.20 30-June-2015
+--------------------------
+
+1. Callouts with string arguments have been added.
+
+2. Assertion code generator in JIT has been optimized.
+
+3. The invalid pattern (?(?C) has a missing assertion condition at the end. The
+pcre2_compile() function read past the end of the input before diagnosing an
+error. This bug was discovered by the LLVM fuzzer.
+
+4. Implemented pcre2_callout_enumerate().
+
+5. Fix JIT compilation of conditional blocks whose assertion is converted to
+(*FAIL). E.g: /(?(?!))/.
+
+6. The pattern /(?(?!)^)/ caused references to random memory. This bug was
+discovered by the LLVM fuzzer.
+
+7. The assertion (?!) is optimized to (*FAIL). This was not handled correctly
+when this assertion was used as a condition, for example (?(?!)a|b). In
+pcre2_match() it worked by luck; in pcre2_dfa_match() it gave an incorrect
+error about an unsupported item.
+
+8. For some types of pattern, for example /Z*(|d*){216}/, the auto-
+possessification code could take exponential time to complete. A recursion
+depth limit of 1000 has been imposed to limit the resources used by this
+optimization. This infelicity was discovered by the LLVM fuzzer.
+
+9. A pattern such as /(*UTF)[\S\V\H]/, which contains a negated special class
+such as \S in non-UCP mode, explicit wide characters (> 255) can be ignored
+because \S ensures they are all in the class. The code for doing this was
+interacting badly with the code for computing the amount of space needed to
+compile the pattern, leading to a buffer overflow. This bug was discovered by
+the LLVM fuzzer.
+
+10. A pattern such as /((?2)+)((?1))/ which has mutual recursion nested inside
+other kinds of group caused stack overflow at compile time. This bug was
+discovered by the LLVM fuzzer.
+
+11. A pattern such as /(?1)(?#?'){8}(a)/ which had a parenthesized comment
+between a subroutine call and its quantifier was incorrectly compiled, leading
+to buffer overflow or other errors. This bug was discovered by the LLVM fuzzer.
+
+12. The illegal pattern /(?(?<E>.*!.*)?)/ was not being diagnosed as missing an
+assertion after (?(. The code was failing to check the character after (?(?<
+for the ! or = that would indicate a lookbehind assertion. This bug was
+discovered by the LLVM fuzzer.
+
+13. A pattern such as /X((?2)()*+){2}+/ which has a possessive quantifier with
+a fixed maximum following a group that contains a subroutine reference was
+incorrectly compiled and could trigger buffer overflow. This bug was discovered
+by the LLVM fuzzer.
+
+14. Negative relative recursive references such as (?-7) to non-existent
+subpatterns were not being diagnosed and could lead to unpredictable behaviour.
+This bug was discovered by the LLVM fuzzer.
+
+15. The bug fixed in 14 was due to an integer variable that was unsigned when
+it should have been signed. Some other "int" variables, having been checked,
+have either been changed to uint32_t or commented as "must be signed".
+
+16. A mutual recursion within a lookbehind assertion such as (?<=((?2))((?1)))
+caused a stack overflow instead of the diagnosis of a non-fixed length
+lookbehind assertion. This bug was discovered by the LLVM fuzzer.
+
+17. The use of \K in a positive lookbehind assertion in a non-anchored pattern
+(e.g. /(?<=\Ka)/) could make pcre2grep loop.
+
+18. There was a similar problem to 17 in pcre2test for global matches, though
+the code there did catch the loop.
+
+19. If a greedy quantified \X was preceded by \C in UTF mode (e.g. \C\X*),
+and a subsequent item in the pattern caused a non-match, backtracking over the
+repeated \X did not stop, but carried on past the start of the subject, causing
+reference to random memory and/or a segfault. There were also some other cases
+where backtracking after \C could crash. This set of bugs was discovered by the
+LLVM fuzzer.
+
+20. The function for finding the minimum length of a matching string could take
+a very long time if mutual recursion was present many times in a pattern, for
+example, /((?2){73}(?2))((?1))/. A better mutual recursion detection method has
+been implemented. This infelicity was discovered by the LLVM fuzzer.
+
+21. Implemented PCRE2_NEVER_BACKSLASH_C.
+
+22. The feature for string replication in pcre2test could read from freed
+memory if the replication required a buffer to be extended, and it was not
+working properly in 16-bit and 32-bit modes. This issue was discovered by a
+fuzzer: see http://lcamtuf.coredump.cx/afl/.
+
+23. Added the PCRE2_ALT_CIRCUMFLEX option.
+
+24. Adjust the treatment of \8 and \9 to be the same as the current Perl
+behaviour.
+
+25. Static linking against the PCRE2 library using the pkg-config module was
+failing on missing pthread symbols.
+
+26. If a group that contained a recursive back reference also contained a
+forward reference subroutine call followed by a non-forward-reference
+subroutine call, for example /.((?2)(?R)\1)()/, pcre2_compile() failed to
+compile correct code, leading to undefined behaviour or an internally detected
+error. This bug was discovered by the LLVM fuzzer.
+
+27. Quantification of certain items (e.g. atomic back references) could cause
+incorrect code to be compiled when recursive forward references were involved.
+For example, in this pattern: /(?1)()((((((\1++))\x85)+)|))/. This bug was
+discovered by the LLVM fuzzer.
+
+28. A repeated conditional group whose condition was a reference by name caused
+a buffer overflow if there was more than one group with the given name. This
+bug was discovered by the LLVM fuzzer.
+
+29. A recursive back reference by name within a group that had the same name as
+another group caused a buffer overflow. For example: /(?J)(?'d'(?'d'\g{d}))/.
+This bug was discovered by the LLVM fuzzer.
+
+30. A forward reference by name to a group whose number is the same as the
+current group, for example in this pattern: /(?|(\k'Pm')|(?'Pm'))/, caused a
+buffer overflow at compile time. This bug was discovered by the LLVM fuzzer.
+
+31. Fix -fsanitize=undefined warnings for left shifts of 1 by 31 (it treats 1
+as an int; fixed by writing it as 1u).
+
+32. Fix pcre2grep compile when -std=c99 is used with gcc, though it still gives
+a warning for "fileno" unless -std=gnu99 us used.
+
+33. A lookbehind assertion within a set of mutually recursive subpatterns could
+provoke a buffer overflow. This bug was discovered by the LLVM fuzzer.
+
+34. Give an error for an empty subpattern name such as (?'').
+
+35. Make pcre2test give an error if a pattern that follows #forbud_utf contains
+\P, \p, or \X.
+
+36. The way named subpatterns are handled has been refactored. There is now a
+pre-pass over the regex which does nothing other than identify named
+subpatterns and count the total captures. This means that information about
+named patterns is known before the rest of the compile. In particular, it means
+that forward references can be checked as they are encountered. Previously, the
+code for handling forward references was contorted and led to several errors in
+computing the memory requirements for some patterns, leading to buffer
+overflows.
+
+37. There was no check for integer overflow in subroutine calls such as (?123).
+
+38. The table entry for \l in EBCDIC environments was incorrect, leading to its
+being treated as a literal 'l' instead of causing an error.
+
+39. If a non-capturing group containing a conditional group that could match
+an empty string was repeated, it was not identified as matching an empty string
+itself. For example: /^(?:(?(1)x|)+)+$()/.
+
+40. In an EBCDIC environment, pcretest was mishandling the escape sequences
+\a and \e in test subject lines.
+
+41. In an EBCDIC environment, \a in a pattern was converted to the ASCII
+instead of the EBCDIC value.
+
+42. The handling of \c in an EBCDIC environment has been revised so that it is
+now compatible with the specification in Perl's perlebcdic page.
+
+43. Single character repetition in JIT has been improved. 20-30% speedup
+was achieved on certain patterns.
+
+44. The EBCDIC character 0x41 is a non-breaking space, equivalent to 0xa0 in
+ASCII/Unicode. This has now been added to the list of characters that are
+recognized as white space in EBCDIC.
+
+45. When PCRE2 was compiled without Unicode support, the use of \p and \P gave
+an error (correctly) when used outside a class, but did not give an error
+within a class.
+
+46. \h within a class was incorrectly compiled in EBCDIC environments.
+
+47. JIT should return with error when the compiled pattern requires
+more stack space than the maximum.
+
+48. Fixed a memory leak in pcre2grep when a locale is set.
+
+
+Version 10.10 06-March-2015
+---------------------------
+
+1. When a pattern is compiled, it remembers the highest back reference so that
+when matching, if the ovector is too small, extra memory can be obtained to
+use instead. A conditional subpattern whose condition is a check on a capture
+having happened, such as, for example in the pattern /^(?:(a)|b)(?(1)A|B)/, is
+another kind of back reference, but it was not setting the highest
+backreference number. This mattered only if pcre2_match() was called with an
+ovector that was too small to hold the capture, and there was no other kind of
+back reference (a situation which is probably quite rare). The effect of the
+bug was that the condition was always treated as FALSE when the capture could
+not be consulted, leading to a incorrect behaviour by pcre2_match(). This bug
+has been fixed.
+
+2. Functions for serialization and deserialization of sets of compiled patterns
+have been added.
+
+3. The value that is returned by PCRE2_INFO_SIZE has been corrected to remove
+excess code units at the end of the data block that may occasionally occur if
+the code for calculating the size over-estimates. This change stops the
+serialization code copying uninitialized data, to which valgrind objects. The
+documentation of PCRE2_INFO_SIZE was incorrect in stating that the size did not
+include the general overhead. This has been corrected.
+
+4. All code units in every slot in the table of group names are now set, again
+in order to avoid accessing uninitialized data when serializing.
+
+5. The (*NO_JIT) feature is implemented.
+
+6. If a bug that caused pcre2_compile() to use more memory than allocated was
+triggered when using valgrind, the code in (3) above passed a stupidly large
+value to valgrind. This caused a crash instead of an "internal error" return.
+
+7. A reference to a duplicated named group (either a back reference or a test
+for being set in a conditional) that occurred in a part of the pattern where
+PCRE2_DUPNAMES was not set caused the amount of memory needed for the pattern
+to be incorrectly calculated, leading to overwriting.
+
+8. A mutually recursive set of back references such as (\2)(\1) caused a
+segfault at compile time (while trying to find the minimum matching length).
+The infinite loop is now broken (with the minimum length unset, that is, zero).
+
+9. If an assertion that was used as a condition was quantified with a minimum
+of zero, matching went wrong. In particular, if the whole group had unlimited
+repetition and could match an empty string, a segfault was likely. The pattern
+(?(?=0)?)+ is an example that caused this. Perl allows assertions to be
+quantified, but not if they are being used as conditions, so the above pattern
+is faulted by Perl. PCRE2 has now been changed so that it also rejects such
+patterns.
+
+10. The error message for an invalid quantifier has been changed from "nothing
+to repeat" to "quantifier does not follow a repeatable item".
+
+11. If a bad UTF string is compiled with NO_UTF_CHECK, it may succeed, but
+scanning the compiled pattern in subsequent auto-possessification can get out
+of step and lead to an unknown opcode. Previously this could have caused an
+infinite loop. Now it generates an "internal error" error. This is a tidyup,
+not a bug fix; passing bad UTF with NO_UTF_CHECK is documented as having an
+undefined outcome.
+
+12. A UTF pattern containing a "not" match of a non-ASCII character and a
+subroutine reference could loop at compile time. Example: /[^\xff]((?1))/.
+
+13. The locale test (RunTest 3) has been upgraded. It now checks that a locale
+that is found in the output of "locale -a" can actually be set by pcre2test
+before it is accepted. Previously, in an environment where a locale was listed
+but would not set (an example does exist), the test would "pass" without
+actually doing anything. Also the fr_CA locale has been added to the list of
+locales that can be used.
+
+14. Fixed a bug in pcre2_substitute(). If a replacement string ended in a
+capturing group number without parentheses, the last character was incorrectly
+literally included at the end of the replacement string.
+
+15. A possessive capturing group such as (a)*+ with a minimum repeat of zero
+failed to allow the zero-repeat case if pcre2_match() was called with an
+ovector too small to capture the group.
+
+16. Improved error message in pcre2test when setting the stack size (-S) fails.
+
+17. Fixed two bugs in CMakeLists.txt: (1) Some lines had got lost in the
+transfer from PCRE1, meaning that CMake configuration failed if "build tests"
+was selected. (2) The file src/pcre2_serialize.c had not been added to the list
+of PCRE2 sources, which caused a failure to build pcre2test.
+
+18. Fixed typo in pcre2_serialize.c (DECL instead of DEFN) that causes problems
+only on Windows.
+
+19. Use binary input when reading back saved serialized patterns in pcre2test.
+
+20. Added RunTest.bat for running the tests under Windows.
+
+21. "make distclean" was not removing config.h, a file that may be created for
+use with CMake.
+
+22. A pattern such as "((?2){0,1999}())?", which has a group containing a
+forward reference repeated a large (but limited) number of times within a
+repeated outer group that has a zero minimum quantifier, caused incorrect code
+to be compiled, leading to the error "internal error: previously-checked
+referenced subpattern not found" when an incorrect memory address was read.
+This bug was reported as "heap overflow", discovered by Kai Lu of Fortinet's
+FortiGuard Labs. (Added 24-March-2015: CVE-2015-2325 was given to this.)
+
+23. A pattern such as "((?+1)(\1))/" containing a forward reference subroutine
+call within a group that also contained a recursive back reference caused
+incorrect code to be compiled. This bug was reported as "heap overflow",
+discovered by Kai Lu of Fortinet's FortiGuard Labs. (Added 24-March-2015:
+CVE-2015-2326 was given to this.)
+
+24. Computing the size of the JIT read-only data in advance has been a source
+of various issues, and new ones are still appear unfortunately. To fix
+existing and future issues, size computation is eliminated from the code,
+and replaced by on-demand memory allocation.
+
+25. A pattern such as /(?i)[A-`]/, where characters in the other case are
+adjacent to the end of the range, and the range contained characters with more
+than one other case, caused incorrect behaviour when compiled in UTF mode. In
+that example, the range a-j was left out of the class.
+
+
+Version 10.00 05-January-2015
+-----------------------------
+
+Version 10.00 is the first release of PCRE2, a revised API for the PCRE
+library. Changes prior to 10.00 are logged in the ChangeLog file for the old
+API, up to item 20 for release 8.36.
+
+The code of the library was heavily revised as part of the new API
+implementation. Details of each and every modification were not individually
+logged. In addition to the API changes, the following changes were made. They
+are either new functionality, or bug fixes and other noticeable changes of
+behaviour that were implemented after the code had been forked.
+
+1. Including Unicode support at build time is now enabled by default, but it
+can optionally be disabled. It is not enabled by default at run time (no
+change).
+
+2. The test program, now called pcre2test, was re-specified and almost
+completely re-written. Its input is not compatible with input for pcretest.
+
+3. Patterns may start with (*NOTEMPTY) or (*NOTEMPTY_ATSTART) to set the
+PCRE2_NOTEMPTY or PCRE2_NOTEMPTY_ATSTART options for every subject line that is
+matched by that pattern.
+
+4. For the benefit of those who use PCRE2 via some other application, that is,
+not writing the function calls themselves, it is possible to check the PCRE2
+version by matching a pattern such as /(?(VERSION>=10)yes|no)/ against a
+string such as "yesno".
+
+5. There are case-equivalent Unicode characters whose encodings use different
+numbers of code units in UTF-8. U+023A and U+2C65 are one example. (It is
+theoretically possible for this to happen in UTF-16 too.) If a backreference to
+a group containing one of these characters was greedily repeated, and during
+the match a backtrack occurred, the subject might be backtracked by the wrong
+number of code units. For example, if /^(\x{23a})\1*(.)/ is matched caselessly
+(and in UTF-8 mode) against "\x{23a}\x{2c65}\x{2c65}\x{2c65}", group 2 should
+capture the final character, which is the three bytes E2, B1, and A5 in UTF-8.
+Incorrect backtracking meant that group 2 captured only the last two bytes.
+This bug has been fixed; the new code is slower, but it is used only when the
+strings matched by the repetition are not all the same length.
+
+6. A pattern such as /()a/ was not setting the "first character must be 'a'"
+information. This applied to any pattern with a group that matched no
+characters, for example: /(?:(?=.)|(?<!x))a/.
+
+7. When an (*ACCEPT) is triggered inside capturing parentheses, it arranges for
+those parentheses to be closed with whatever has been captured so far. However,
+it was failing to mark any other groups between the highest capture so far and
+the currrent group as "unset". Thus, the ovector for those groups contained
+whatever was previously there. An example is the pattern /(x)|((*ACCEPT))/ when
+matched against "abcd".
+
+8. The pcre2_substitute() function has been implemented.
+
+9. If an assertion used as a condition was quantified with a minimum of zero
+(an odd thing to do, but it happened), SIGSEGV or other misbehaviour could
+occur.
+
+10. The PCRE2_NO_DOTSTAR_ANCHOR option has been implemented.
+
+****