/[pcre]/code/trunk/pcre_compile.c

Diff of /code/trunk/pcre_compile.c

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-revision 226 by ph10,
Tue Aug 21 11:46:08 2007 UTC
+revision 503 by ph10,
Sun Mar  7 17:35:52 2010 UTC
 Line 6
  and semantics are as close as possible to those of the Perl 5 language.
                         Written by Philip Hazel
-            Copyright (c) 1997-2007 University of Cambridge
+            Copyright (c) 1997-2010 University of Cambridge
  -----------------------------------------------------------------------------
  Redistribution and use in source and binary forms, with or without
 Line 43 
 supporting internal functions that are n
  #ifdef HAVE_CONFIG_H
- #include <config.h>
+ #include "config.h"
  #endif
  #define NLBLOCK cd             /* Block containing newline information */
 Line 53 
 supporting internal functions that are n
  #include "pcre_internal.h"
- /* When DEBUG is defined, we need the pcre_printint() function, which is also
+ /* When PCRE_DEBUG is defined, we need the pcre_printint() function, which is
- used by pcretest. DEBUG is not defined when building a production library. */
+ also used by pcretest. PCRE_DEBUG is not defined when building a production
+ library. */
- #ifdef DEBUG
+ #ifdef PCRE_DEBUG
  #include "pcre_printint.src"
  #endif
-Line 97 
 are simple data values; negative values
+Line 98 
 are simple data values; negative values
  on. Zero means further processing is needed (for things like \x), or the escape
  is invalid. */
- #ifndef EBCDIC  /* This is the "normal" table for ASCII systems */
+ #ifndef EBCDIC
+ /* This is the "normal" table for ASCII systems or for EBCDIC systems running
+ in UTF-8 mode. */
  static const short int escapes[] = {
-,      0,      0,      0,      0,      0,      0,      0,   /* 0 - 7 */
+,                       0,
-,      0,    ':',    ';',    '<',    '=',    '>',    '?',   /* 8 - ? */
+,                       0,
-    '@', -ESC_A, -ESC_B, -ESC_C, -ESC_D, -ESC_E,      0, -ESC_G,   /* @ - G */
+,                       0,
- -ESC_H,      0,      0, -ESC_K,      0,      0,      0,      0,   /* H - O */
+,                       0,
- -ESC_P, -ESC_Q, -ESC_R, -ESC_S,      0,      0, -ESC_V, -ESC_W,   /* P - W */
+,                       0,
- -ESC_X,      0, -ESC_Z,    '[',   '\\',    ']',    '^',    '_',   /* X - _ */
+      CHAR_COLON,              CHAR_SEMICOLON,
-    '`',      7, -ESC_b,      0, -ESC_d,  ESC_e,  ESC_f,      0,   /* ` - g */
+      CHAR_LESS_THAN_SIGN,     CHAR_EQUALS_SIGN,
- -ESC_h,      0,      0, -ESC_k,      0,      0,  ESC_n,      0,   /* h - o */
+      CHAR_GREATER_THAN_SIGN,  CHAR_QUESTION_MARK,
- -ESC_p,      0,  ESC_r, -ESC_s,  ESC_tee,    0, -ESC_v, -ESC_w,   /* p - w */
+      CHAR_COMMERCIAL_AT,      -ESC_A,
-,      0, -ESC_z                                            /* x - z */
+      -ESC_B,                  -ESC_C,
+      -ESC_D,                  -ESC_E,
+,                       -ESC_G,
+      -ESC_H,                  0,
+,                       -ESC_K,
+,                       0,
+,                       0,
+      -ESC_P,                  -ESC_Q,
+      -ESC_R,                  -ESC_S,
+,                       0,
+      -ESC_V,                  -ESC_W,
+      -ESC_X,                  0,
+      -ESC_Z,                  CHAR_LEFT_SQUARE_BRACKET,
+      CHAR_BACKSLASH,          CHAR_RIGHT_SQUARE_BRACKET,
+      CHAR_CIRCUMFLEX_ACCENT,  CHAR_UNDERSCORE,
+      CHAR_GRAVE_ACCENT,       7,
+      -ESC_b,                  0,
+      -ESC_d,                  ESC_e,
+      ESC_f,                   0,
+      -ESC_h,                  0,
+,                       -ESC_k,
+,                       0,
+      ESC_n,                   0,
+      -ESC_p,                  0,
+      ESC_r,                   -ESC_s,
+      ESC_tee,                 0,
+      -ESC_v,                  -ESC_w,
+,                       0,
+      -ESC_z
  };
- #else           /* This is the "abnormal" table for EBCDIC systems */
+ #else
+ /* This is the "abnormal" table for EBCDIC systems without UTF-8 support. */
  static const short int escapes[] = {
  /*  48 */     0,     0,      0,     '.',    '<',   '(',    '+',    '|',
  /*  50 */   '&',     0,      0,       0,      0,     0,      0,      0,
-Line 140 
 static const short int escapes[] = {
+Line 176 
 static const short int escapes[] = {
  #endif
- /* Table of special "verbs" like (*PRUNE) */
+ /* Table of special "verbs" like (*PRUNE). This is a short table, so it is
+ searched linearly. Put all the names into a single string, in order to reduce
+ the number of relocations when a shared library is dynamically linked. The
+ string is built from string macros so that it works in UTF-8 mode on EBCDIC
+ platforms. */
  typedef struct verbitem {
-   const char *name;
    int   len;
    int   op;
  } verbitem;
- static verbitem verbs[] = {
+ static const char verbnames[] =
-   { "ACCEPT", 6, OP_ACCEPT },
+   STRING_ACCEPT0
-   { "COMMIT", 6, OP_COMMIT },
+   STRING_COMMIT0
-   { "F",      1, OP_FAIL },
+   STRING_F0
-   { "FAIL",   4, OP_FAIL },
+   STRING_FAIL0
-   { "PRUNE",  5, OP_PRUNE },
+   STRING_PRUNE0
-   { "SKIP",   4, OP_SKIP  },
+   STRING_SKIP0
-   { "THEN",   4, OP_THEN  }
+   STRING_THEN;
+ static const verbitem verbs[] = {
+   { 6, OP_ACCEPT },
+   { 6, OP_COMMIT },
+   { 1, OP_FAIL },
+   { 4, OP_FAIL },
+   { 5, OP_PRUNE },
+   { 4, OP_SKIP  },
+   { 4, OP_THEN  }
  };
- static int verbcount = sizeof(verbs)/sizeof(verbitem);
+ static const int verbcount = sizeof(verbs)/sizeof(verbitem);
- /* Tables of names of POSIX character classes and their lengths. The list is
- terminated by a zero length entry. The first three must be alpha, lower, upper,
- as this is assumed for handling case independence. */
- static const char *const posix_names[] = {
+ /* Tables of names of POSIX character classes and their lengths. The names are
-   "alpha", "lower", "upper",
+ now all in a single string, to reduce the number of relocations when a shared
-   "alnum", "ascii", "blank", "cntrl", "digit", "graph",
+ library is dynamically loaded. The list of lengths is terminated by a zero
-   "print", "punct", "space", "word",  "xdigit" };
+ length entry. The first three must be alpha, lower, upper, as this is assumed
+ for handling case independence. */
+ static const char posix_names[] =
+   STRING_alpha0 STRING_lower0 STRING_upper0 STRING_alnum0
+   STRING_ascii0 STRING_blank0 STRING_cntrl0 STRING_digit0
+   STRING_graph0 STRING_print0 STRING_punct0 STRING_space0
+   STRING_word0  STRING_xdigit;
  static const uschar posix_name_lengths[] = {
 , 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 6, 0 };
-Line 207 
 static const int posix_class_maps[] = {
+Line 258 
 static const int posix_class_maps[] = {
  /* The texts of compile-time error messages. These are "char *" because they
  are passed to the outside world. Do not ever re-use any error number, because
  they are documented. Always add a new error instead. Messages marked DEAD below
- are no longer used. */
+ are no longer used. This used to be a table of strings, but in order to reduce
+ the number of relocations needed when a shared library is loaded dynamically,
- static const char *error_texts[] = {
+ it is now one long string. We cannot use a table of offsets, because the
-   "no error",
+ lengths of inserts such as XSTRING(MAX_NAME_SIZE) are not known. Instead, we
-   "\\ at end of pattern",
+ simply count through to the one we want - this isn't a performance issue
-   "\\c at end of pattern",
+ because these strings are used only when there is a compilation error.
-   "unrecognized character follows \\",
-   "numbers out of order in {} quantifier",
+ Each substring ends with \0 to insert a null character. This includes the final
+ substring, so that the whole string ends with \0\0, which can be detected when
+ counting through. */
+ static const char error_texts[] =
+   "no error\0"
+   "\\ at end of pattern\0"
+   "\\c at end of pattern\0"
+   "unrecognized character follows \\\0"
+   "numbers out of order in {} quantifier\0"
    /* 5 */
-   "number too big in {} quantifier",
+   "number too big in {} quantifier\0"
-   "missing terminating ] for character class",
+   "missing terminating ] for character class\0"
-   "invalid escape sequence in character class",
+   "invalid escape sequence in character class\0"
-   "range out of order in character class",
+   "range out of order in character class\0"
-   "nothing to repeat",
+   "nothing to repeat\0"
    /* 10 */
-   "operand of unlimited repeat could match the empty string",  /** DEAD **/
+   "operand of unlimited repeat could match the empty string\0"  /** DEAD **/
-   "internal error: unexpected repeat",
+   "internal error: unexpected repeat\0"
-   "unrecognized character after (?",
+   "unrecognized character after (? or (?-\0"
-   "POSIX named classes are supported only within a class",
+   "POSIX named classes are supported only within a class\0"
-   "missing )",
+   "missing )\0"
    /* 15 */
-   "reference to non-existent subpattern",
+   "reference to non-existent subpattern\0"
-   "erroffset passed as NULL",
+   "erroffset passed as NULL\0"
-   "unknown option bit(s) set",
+   "unknown option bit(s) set\0"
-   "missing ) after comment",
+   "missing ) after comment\0"
-   "parentheses nested too deeply",  /** DEAD **/
+   "parentheses nested too deeply\0"  /** DEAD **/
    /* 20 */
-   "regular expression is too large",
+   "regular expression is too large\0"
-   "failed to get memory",
+   "failed to get memory\0"
-   "unmatched parentheses",
+   "unmatched parentheses\0"
-   "internal error: code overflow",
+   "internal error: code overflow\0"
-   "unrecognized character after (?<",
+   "unrecognized character after (?<\0"
    /* 25 */
-   "lookbehind assertion is not fixed length",
+   "lookbehind assertion is not fixed length\0"
-   "malformed number or name after (?(",
+   "malformed number or name after (?(\0"
-   "conditional group contains more than two branches",
+   "conditional group contains more than two branches\0"
-   "assertion expected after (?(",
+   "assertion expected after (?(\0"
-   "(?R or (?[+-]digits must be followed by )",
+   "(?R or (?[+-]digits must be followed by )\0"
    /* 30 */
-   "unknown POSIX class name",
+   "unknown POSIX class name\0"
-   "POSIX collating elements are not supported",
+   "POSIX collating elements are not supported\0"
-   "this version of PCRE is not compiled with PCRE_UTF8 support",
+   "this version of PCRE is not compiled with PCRE_UTF8 support\0"
-   "spare error",  /** DEAD **/
+   "spare error\0"  /** DEAD **/
-   "character value in \\x{...} sequence is too large",
+   "character value in \\x{...} sequence is too large\0"
    /* 35 */
-   "invalid condition (?(0)",
+   "invalid condition (?(0)\0"
-   "\\C not allowed in lookbehind assertion",
+   "\\C not allowed in lookbehind assertion\0"
-   "PCRE does not support \\L, \\l, \\N, \\U, or \\u",
+   "PCRE does not support \\L, \\l, \\N, \\U, or \\u\0"
-   "number after (?C is > 255",
+   "number after (?C is > 255\0"
-   "closing ) for (?C expected",
+   "closing ) for (?C expected\0"
    /* 40 */
-   "recursive call could loop indefinitely",
+   "recursive call could loop indefinitely\0"
-   "unrecognized character after (?P",
+   "unrecognized character after (?P\0"
-   "syntax error in subpattern name (missing terminator)",
+   "syntax error in subpattern name (missing terminator)\0"
-   "two named subpatterns have the same name",
+   "two named subpatterns have the same name\0"
-   "invalid UTF-8 string",
+   "invalid UTF-8 string\0"
    /* 45 */
-   "support for \\P, \\p, and \\X has not been compiled",
+   "support for \\P, \\p, and \\X has not been compiled\0"
-   "malformed \\P or \\p sequence",
+   "malformed \\P or \\p sequence\0"
-   "unknown property name after \\P or \\p",
+   "unknown property name after \\P or \\p\0"
-   "subpattern name is too long (maximum " XSTRING(MAX_NAME_SIZE) " characters)",
+   "subpattern name is too long (maximum " XSTRING(MAX_NAME_SIZE) " characters)\0"
-   "too many named subpatterns (maximum " XSTRING(MAX_NAME_COUNT) ")",
+   "too many named subpatterns (maximum " XSTRING(MAX_NAME_COUNT) ")\0"
    /* 50 */
-   "repeated subpattern is too long",    /** DEAD **/
+   "repeated subpattern is too long\0"    /** DEAD **/
-   "octal value is greater than \\377 (not in UTF-8 mode)",
+   "octal value is greater than \\377 (not in UTF-8 mode)\0"
-   "internal error: overran compiling workspace",
+   "internal error: overran compiling workspace\0"
-   "internal error: previously-checked referenced subpattern not found",
+   "internal error: previously-checked referenced subpattern not found\0"
-   "DEFINE group contains more than one branch",
+   "DEFINE group contains more than one branch\0"
    /* 55 */
-   "repeating a DEFINE group is not allowed",
+   "repeating a DEFINE group is not allowed\0"
-   "inconsistent NEWLINE options",
+   "inconsistent NEWLINE options\0"
-   "\\g is not followed by a braced name or an optionally braced non-zero number",
+   "\\g is not followed by a braced, angle-bracketed, or quoted name/number or by a plain number\0"
-   "(?+ or (?- or (?(+ or (?(- must be followed by a non-zero number",
+   "a numbered reference must not be zero\0"
-   "(*VERB) with an argument is not supported",
+   "(*VERB) with an argument is not supported\0"
    /* 60 */
-   "(*VERB) not recognized",
+   "(*VERB) not recognized\0"
-   "number is too big"
+   "number is too big\0"
- };
+   "subpattern name expected\0"
+   "digit expected after (?+\0"
+   "] is an invalid data character in JavaScript compatibility mode\0"
+   /* 65 */
+   "different names for subpatterns of the same number are not allowed\0";
  /* Table to identify digits and hex digits. This is used when compiling
  patterns. Note that the tables in chartables are dependent on the locale, and
-Line 303 
 For convenience, we use the same bit def
+Line 366 
 For convenience, we use the same bit def
  Then we can use ctype_digit and ctype_xdigit in the code. */
- #ifndef EBCDIC  /* This is the "normal" case, for ASCII systems */
+ #ifndef EBCDIC
+ /* This is the "normal" case, for ASCII systems, and EBCDIC systems running in
+ UTF-8 mode. */
  static const unsigned char digitab[] =
    {
 x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   0-  7 */
-Line 339 
 static const unsigned char digitab[] =
+Line 406 
 static const unsigned char digitab[] =
 x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /* 240-247 */
 x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00};/* 248-255 */
- #else           /* This is the "abnormal" case, for EBCDIC systems */
+ #else
+ /* This is the "abnormal" case, for EBCDIC systems not running in UTF-8 mode. */
  static const unsigned char digitab[] =
    {
 x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, /*   0-  7  0 */
-Line 420 
 static BOOL
+Line 490 
 static BOOL
  /*************************************************
+ *            Find an error text                  *
+ *************************************************/
+ /* The error texts are now all in one long string, to save on relocations. As
+ some of the text is of unknown length, we can't use a table of offsets.
+ Instead, just count through the strings. This is not a performance issue
+ because it happens only when there has been a compilation error.
+ Argument:   the error number
+ Returns:    pointer to the error string
+ */
+ static const char *
+ find_error_text(int n)
+ {
+ const char *s = error_texts;
+ for (; n > 0; n--)
+   {
+   while (*s++ != 0) {};
+   if (*s == 0) return "Error text not found (please report)";
+   }
+ return s;
+ }
+ /*************************************************
  *            Handle escapes                      *
  *************************************************/
-Line 458 
 ptr--;                            /* Set
+Line 554 
 ptr--;                            /* Set
  if (c == 0) *errorcodeptr = ERR1;
- /* Non-alphamerics are literals. For digits or letters, do an initial lookup in
+ /* Non-alphanumerics are literals. For digits or letters, do an initial lookup
- a table. A non-zero result is something that can be returned immediately.
+ in a table. A non-zero result is something that can be returned immediately.
  Otherwise further processing may be required. */
- #ifndef EBCDIC  /* ASCII coding */
+ #ifndef EBCDIC  /* ASCII/UTF-8 coding */
- else if (c < '0' || c > 'z') {}                           /* Not alphameric */
+ else if (c < CHAR_0 || c > CHAR_z) {}                     /* Not alphanumeric */
- else if ((i = escapes[c - '0']) != 0) c = i;
+ else if ((i = escapes[c - CHAR_0]) != 0) c = i;
  #else           /* EBCDIC coding */
- else if (c < 'a' || (ebcdic_chartab[c] & 0x0E) == 0) {}   /* Not alphameric */
+ else if (c < 'a' || (ebcdic_chartab[c] & 0x0E) == 0) {}   /* Not alphanumeric */
  else if ((i = escapes[c - 0x48]) != 0)  c = i;
  #endif
-Line 483 
 else
+Line 579 
 else
      /* A number of Perl escapes are not handled by PCRE. We give an explicit
      error. */
-     case 'l':
+     case CHAR_l:
-     case 'L':
+     case CHAR_L:
-     case 'N':
+     case CHAR_N:
-     case 'u':
+     case CHAR_u:
-     case 'U':
+     case CHAR_U:
      *errorcodeptr = ERR37;
      break;
-     /* \g must be followed by a number, either plain or braced. If positive, it
+     /* \g must be followed by one of a number of specific things:
-     is an absolute backreference. If negative, it is a relative backreference.
-     This is a Perl 5.10 feature. Perl 5.10 also supports \g{name} as a
+     (1) A number, either plain or braced. If positive, it is an absolute
-     reference to a named group. This is part of Perl's movement towards a
+     backreference. If negative, it is a relative backreference. This is a Perl
-     unified syntax for back references. As this is synonymous with \k{name}, we
+.10 feature.
-     fudge it up by pretending it really was \k. */
+     (2) Perl 5.10 also supports \g{name} as a reference to a named group. This
+     is part of Perl's movement towards a unified syntax for back references. As
+     this is synonymous with \k{name}, we fudge it up by pretending it really
+     was \k.
+     (3) For Oniguruma compatibility we also support \g followed by a name or a
+     number either in angle brackets or in single quotes. However, these are
+     (possibly recursive) subroutine calls, _not_ backreferences. Just return
+     the -ESC_g code (cf \k). */
-     case 'g':
+     case CHAR_g:
-     if (ptr[1] == '{')
+     if (ptr[1] == CHAR_LESS_THAN_SIGN || ptr[1] == CHAR_APOSTROPHE)
+       {
+       c = -ESC_g;
+       break;
+       }
+     /* Handle the Perl-compatible cases */
+     if (ptr[1] == CHAR_LEFT_CURLY_BRACKET)
        {
        const uschar *p;
-       for (p = ptr+2; *p != 0 && *p != '}'; p++)
+       for (p = ptr+2; *p != 0 && *p != CHAR_RIGHT_CURLY_BRACKET; p++)
-         if (*p != '-' && (digitab[*p] & ctype_digit) == 0) break;
+         if (*p != CHAR_MINUS && (digitab[*p] & ctype_digit) == 0) break;
-       if (*p != 0 && *p != '}')
+       if (*p != 0 && *p != CHAR_RIGHT_CURLY_BRACKET)
          {
          c = -ESC_k;
          break;
-Line 514 
 else
+Line 627 
 else
        }
      else braced = FALSE;
-     if (ptr[1] == '-')
+     if (ptr[1] == CHAR_MINUS)
        {
        negated = TRUE;
        ptr++;
-Line 523 
 else
+Line 636 
 else
      c = 0;
      while ((digitab[ptr[1]] & ctype_digit) != 0)
-       c = c * 10 + *(++ptr) - '0';
+       c = c * 10 + *(++ptr) - CHAR_0;
-     if (c < 0)
+     if (c < 0)   /* Integer overflow */
        {
        *errorcodeptr = ERR61;
        break;
        }
-     if (c == 0 || (braced && *(++ptr) != '}'))
+     if (braced && *(++ptr) != CHAR_RIGHT_CURLY_BRACKET)
        {
        *errorcodeptr = ERR57;
        break;
        }
+     if (c == 0)
+       {
+       *errorcodeptr = ERR58;
+       break;
+       }
      if (negated)
        {
        if (c > bracount)
-Line 562 
 else
+Line 681 
 else
      value is greater than 377, the least significant 8 bits are taken. Inside a
      character class, \ followed by a digit is always an octal number. */
-     case '1': case '2': case '3': case '4': case '5':
+     case CHAR_1: case CHAR_2: case CHAR_3: case CHAR_4: case CHAR_5:
-     case '6': case '7': case '8': case '9':
+     case CHAR_6: case CHAR_7: case CHAR_8: case CHAR_9:
      if (!isclass)
        {
        oldptr = ptr;
-       c -= '0';
+       c -= CHAR_0;
        while ((digitab[ptr[1]] & ctype_digit) != 0)
-         c = c * 10 + *(++ptr) - '0';
+         c = c * 10 + *(++ptr) - CHAR_0;
-       if (c < 0)
+       if (c < 0)    /* Integer overflow */
          {
          *errorcodeptr = ERR61;
          break;
-Line 588 
 else
+Line 707 
 else
      generates a binary zero byte and treats the digit as a following literal.
      Thus we have to pull back the pointer by one. */
-     if ((c = *ptr) >= '8')
+     if ((c = *ptr) >= CHAR_8)
        {
        ptr--;
        c = 0;
-Line 601 
 else
+Line 720 
 else
      to do). Nowadays we allow for larger numbers in UTF-8 mode, but no more
      than 3 octal digits. */
-     case '0':
+     case CHAR_0:
-     c -= '0';
+     c -= CHAR_0;
-     while(i++ < 2 && ptr[1] >= '0' && ptr[1] <= '7')
+     while(i++ < 2 && ptr[1] >= CHAR_0 && ptr[1] <= CHAR_7)
-         c = c * 8 + *(++ptr) - '0';
+         c = c * 8 + *(++ptr) - CHAR_0;
      if (!utf8 && c > 255) *errorcodeptr = ERR51;
      break;
-Line 612 
 else
+Line 731 
 else
      than 0xff in utf8 mode, but only if the ddd are hex digits. If not, { is
      treated as a data character. */
-     case 'x':
+     case CHAR_x:
-     if (ptr[1] == '{')
+     if (ptr[1] == CHAR_LEFT_CURLY_BRACKET)
        {
        const uschar *pt = ptr + 2;
        int count = 0;
-Line 622 
 else
+Line 741 
 else
        while ((digitab[*pt] & ctype_xdigit) != 0)
          {
          register int cc = *pt++;
-         if (c == 0 && cc == '0') continue;     /* Leading zeroes */
+         if (c == 0 && cc == CHAR_0) continue;     /* Leading zeroes */
          count++;
- #ifndef EBCDIC  /* ASCII coding */
+ #ifndef EBCDIC  /* ASCII/UTF-8 coding */
-         if (cc >= 'a') cc -= 32;               /* Convert to upper case */
+         if (cc >= CHAR_a) cc -= 32;               /* Convert to upper case */
-         c = (c << 4) + cc - ((cc < 'A')? '0' : ('A' - 10));
+         c = (c << 4) + cc - ((cc < CHAR_A)? CHAR_0 : (CHAR_A - 10));
  #else           /* EBCDIC coding */
-         if (cc >= 'a' && cc <= 'z') cc += 64;  /* Convert to upper case */
+         if (cc >= CHAR_a && cc <= CHAR_z) cc += 64;  /* Convert to upper case */
-         c = (c << 4) + cc - ((cc >= '0')? '0' : ('A' - 10));
+         c = (c << 4) + cc - ((cc >= CHAR_0)? CHAR_0 : (CHAR_A - 10));
  #endif
          }
-       if (*pt == '}')
+       if (*pt == CHAR_RIGHT_CURLY_BRACKET)
          {
          if (c < 0 || count > (utf8? 8 : 2)) *errorcodeptr = ERR34;
          ptr = pt;
-Line 650 
 else
+Line 769 
 else
      c = 0;
      while (i++ < 2 && (digitab[ptr[1]] & ctype_xdigit) != 0)
        {
-       int cc;                               /* Some compilers don't like ++ */
+       int cc;                                  /* Some compilers don't like */
-       cc = *(++ptr);                        /* in initializers */
+       cc = *(++ptr);                           /* ++ in initializers */
- #ifndef EBCDIC  /* ASCII coding */
+ #ifndef EBCDIC  /* ASCII/UTF-8 coding */
-       if (cc >= 'a') cc -= 32;              /* Convert to upper case */
+       if (cc >= CHAR_a) cc -= 32;              /* Convert to upper case */
-       c = c * 16 + cc - ((cc < 'A')? '0' : ('A' - 10));
+       c = c * 16 + cc - ((cc < CHAR_A)? CHAR_0 : (CHAR_A - 10));
  #else           /* EBCDIC coding */
-       if (cc <= 'z') cc += 64;              /* Convert to upper case */
+       if (cc <= CHAR_z) cc += 64;              /* Convert to upper case */
-       c = c * 16 + cc - ((cc >= '0')? '0' : ('A' - 10));
+       c = c * 16 + cc - ((cc >= CHAR_0)? CHAR_0 : (CHAR_A - 10));
  #endif
        }
      break;
-Line 666 
 else
+Line 785 
 else
      This coding is ASCII-specific, but then the whole concept of \cx is
      ASCII-specific. (However, an EBCDIC equivalent has now been added.) */
-     case 'c':
+     case CHAR_c:
      c = *(++ptr);
      if (c == 0)
        {
-Line 674 
 else
+Line 793 
 else
        break;
        }
- #ifndef EBCDIC  /* ASCII coding */
+ #ifndef EBCDIC  /* ASCII/UTF-8 coding */
-     if (c >= 'a' && c <= 'z') c -= 32;
+     if (c >= CHAR_a && c <= CHAR_z) c -= 32;
      c ^= 0x40;
  #else           /* EBCDIC coding */
-     if (c >= 'a' && c <= 'z') c += 64;
+     if (c >= CHAR_a && c <= CHAR_z) c += 64;
      c ^= 0xC0;
  #endif
      break;
      /* PCRE_EXTRA enables extensions to Perl in the matter of escapes. Any
-     other alphameric following \ is an error if PCRE_EXTRA was set; otherwise,
+     other alphanumeric following \ is an error if PCRE_EXTRA was set;
-     for Perl compatibility, it is a literal. This code looks a bit odd, but
+     otherwise, for Perl compatibility, it is a literal. This code looks a bit
-     there used to be some cases other than the default, and there may be again
+     odd, but there used to be some cases other than the default, and there may
-     in future, so I haven't "optimized" it. */
+     be again in future, so I haven't "optimized" it. */
      default:
      if ((options & PCRE_EXTRA) != 0) switch(c)
-Line 740 
 if (c == 0) goto ERROR_RETURN;
+Line 859 
 if (c == 0) goto ERROR_RETURN;
  /* \P or \p can be followed by a name in {}, optionally preceded by ^ for
  negation. */
- if (c == '{')
+ if (c == CHAR_LEFT_CURLY_BRACKET)
    {
-   if (ptr[1] == '^')
+   if (ptr[1] == CHAR_CIRCUMFLEX_ACCENT)
      {
      *negptr = TRUE;
      ptr++;
-Line 751 
 if (c == '{')
+Line 870 
 if (c == '{')
      {
      c = *(++ptr);
      if (c == 0) goto ERROR_RETURN;
-     if (c == '}') break;
+     if (c == CHAR_RIGHT_CURLY_BRACKET) break;
      name[i] = c;
      }
-   if (c !='}') goto ERROR_RETURN;
+   if (c != CHAR_RIGHT_CURLY_BRACKET) goto ERROR_RETURN;
    name[i] = 0;
    }
-Line 776 
 top = _pcre_utt_size;
+Line 895 
 top = _pcre_utt_size;
  while (bot < top)
    {
    i = (bot + top) >> 1;
-   c = strcmp(name, _pcre_utt[i].name);
+   c = strcmp(name, _pcre_utt_names + _pcre_utt[i].name_offset);
    if (c == 0)
      {
      *dptr = _pcre_utt[i].value;
-Line 819 
 is_counted_repeat(const uschar *p)
+Line 938 
 is_counted_repeat(const uschar *p)
  {
  if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
  while ((digitab[*p] & ctype_digit) != 0) p++;
- if (*p == '}') return TRUE;
+ if (*p == CHAR_RIGHT_CURLY_BRACKET) return TRUE;
- if (*p++ != ',') return FALSE;
+ if (*p++ != CHAR_COMMA) return FALSE;
- if (*p == '}') return TRUE;
+ if (*p == CHAR_RIGHT_CURLY_BRACKET) return TRUE;
  if ((digitab[*p++] & ctype_digit) == 0) return FALSE;
  while ((digitab[*p] & ctype_digit) != 0) p++;
- return (*p == '}');
+ return (*p == CHAR_RIGHT_CURLY_BRACKET);
  }
-Line 860 
 int max = -1;
+Line 979 
 int max = -1;
  /* Read the minimum value and do a paranoid check: a negative value indicates
  an integer overflow. */
- while ((digitab[*p] & ctype_digit) != 0) min = min * 10 + *p++ - '0';
+ while ((digitab[*p] & ctype_digit) != 0) min = min * 10 + *p++ - CHAR_0;
  if (min < 0 || min > 65535)
    {
    *errorcodeptr = ERR5;
-Line 870 
 if (min < 0 || min > 65535)
+Line 989 
 if (min < 0 || min > 65535)
  /* Read the maximum value if there is one, and again do a paranoid on its size.
  Also, max must not be less than min. */
- if (*p == '}') max = min; else
+ if (*p == CHAR_RIGHT_CURLY_BRACKET) max = min; else
    {
-   if (*(++p) != '}')
+   if (*(++p) != CHAR_RIGHT_CURLY_BRACKET)
      {
      max = 0;
-     while((digitab[*p] & ctype_digit) != 0) max = max * 10 + *p++ - '0';
+     while((digitab[*p] & ctype_digit) != 0) max = max * 10 + *p++ - CHAR_0;
      if (max < 0 || max > 65535)
        {
        *errorcodeptr = ERR5;
-Line 900 
 return p;
+Line 1019 
 return p;
  /*************************************************
- *       Find forward referenced subpattern       *
+ *  Subroutine for finding forward reference      *
  *************************************************/
- /* This function scans along a pattern's text looking for capturing
+ /* This recursive function is called only from find_parens() below. The
+ top-level call starts at the beginning of the pattern. All other calls must
+ start at a parenthesis. It scans along a pattern's text looking for capturing
  subpatterns, and counting them. If it finds a named pattern that matches the
  name it is given, it returns its number. Alternatively, if the name is NULL, it
- returns when it reaches a given numbered subpattern. This is used for forward
+ returns when it reaches a given numbered subpattern. We know that if (?P< is
- references to subpatterns. We know that if (?P< is encountered, the name will
+ encountered, the name will be terminated by '>' because that is checked in the
- be terminated by '>' because that is checked in the first pass.
+ first pass. Recursion is used to keep track of subpatterns that reset the
+ capturing group numbers - the (?| feature.
  Arguments:
-   ptr          current position in the pattern
+   ptrptr       address of the current character pointer (updated)
-   count        current count of capturing parens so far encountered
+   cd           compile background data
    name         name to seek, or NULL if seeking a numbered subpattern
    lorn         name length, or subpattern number if name is NULL
    xmode        TRUE if we are in /x mode
+   count        pointer to the current capturing subpattern number (updated)
  Returns:       the number of the named subpattern, or -1 if not found
  */
  static int
- find_parens(const uschar *ptr, int count, const uschar *name, int lorn,
+ find_parens_sub(uschar **ptrptr, compile_data *cd, const uschar *name, int lorn,
-   BOOL xmode)
+   BOOL xmode, int *count)
  {
- const uschar *thisname;
+ uschar *ptr = *ptrptr;
+ int start_count = *count;
+ int hwm_count = start_count;
+ BOOL dup_parens = FALSE;
- for (; *ptr != 0; ptr++)
+ /* If the first character is a parenthesis, check on the type of group we are
+ dealing with. The very first call may not start with a parenthesis. */
+ if (ptr[0] == CHAR_LEFT_PARENTHESIS)
    {
-   int term;
+   if (ptr[1] == CHAR_QUESTION_MARK &&
+       ptr[2] == CHAR_VERTICAL_LINE)
+     {
+     ptr += 3;
+     dup_parens = TRUE;
+     }
+   /* Handle a normal, unnamed capturing parenthesis */
+   else if (ptr[1] != CHAR_QUESTION_MARK && ptr[1] != CHAR_ASTERISK)
+     {
+     *count += 1;
+     if (name == NULL && *count == lorn) return *count;
+     ptr++;
+     }
+   /* Handle a condition. If it is an assertion, just carry on so that it
+   is processed as normal. If not, skip to the closing parenthesis of the
+   condition (there can't be any nested parens. */
+   else if (ptr[2] == CHAR_LEFT_PARENTHESIS)
+     {
+     ptr += 2;
+     if (ptr[1] != CHAR_QUESTION_MARK)
+       {
+       while (*ptr != 0 && *ptr != CHAR_RIGHT_PARENTHESIS) ptr++;
+       if (*ptr != 0) ptr++;
+       }
+     }
+   /* We have either (? or (* and not a condition */
+   else
+     {
+     ptr += 2;
+     if (*ptr == CHAR_P) ptr++;                      /* Allow optional P */
+     /* We have to disambiguate (?<! and (?<= from (?<name> for named groups */
+     if ((*ptr == CHAR_LESS_THAN_SIGN && ptr[1] != CHAR_EXCLAMATION_MARK &&
+         ptr[1] != CHAR_EQUALS_SIGN) || *ptr == CHAR_APOSTROPHE)
+       {
+       int term;
+       const uschar *thisname;
+       *count += 1;
+       if (name == NULL && *count == lorn) return *count;
+       term = *ptr++;
+       if (term == CHAR_LESS_THAN_SIGN) term = CHAR_GREATER_THAN_SIGN;
+       thisname = ptr;
+       while (*ptr != term) ptr++;
+       if (name != NULL && lorn == ptr - thisname &&
+           strncmp((const char *)name, (const char *)thisname, lorn) == 0)
+         return *count;
+       term++;
+       }
+     }
+   }
+ /* Past any initial parenthesis handling, scan for parentheses or vertical
+ bars. */
+ for (; *ptr != 0; ptr++)
+   {
    /* Skip over backslashed characters and also entire \Q...\E */
-   if (*ptr == '\\')
+   if (*ptr == CHAR_BACKSLASH)
      {
-     if (*(++ptr) == 0) return -1;
+     if (*(++ptr) == 0) goto FAIL_EXIT;
-     if (*ptr == 'Q') for (;;)
+     if (*ptr == CHAR_Q) for (;;)
        {
-       while (*(++ptr) != 0 && *ptr != '\\');
+       while (*(++ptr) != 0 && *ptr != CHAR_BACKSLASH) {};
-       if (*ptr == 0) return -1;
+       if (*ptr == 0) goto FAIL_EXIT;
-       if (*(++ptr) == 'E') break;
+       if (*(++ptr) == CHAR_E) break;
        }
      continue;
      }
-   /* Skip over character classes */
+   /* Skip over character classes; this logic must be similar to the way they
+   are handled for real. If the first character is '^', skip it. Also, if the
+   first few characters (either before or after ^) are \Q\E or \E we skip them
+   too. This makes for compatibility with Perl. Note the use of STR macros to
+   encode "Q\\E" so that it works in UTF-8 on EBCDIC platforms. */
-   if (*ptr == '[')
+   if (*ptr == CHAR_LEFT_SQUARE_BRACKET)
      {
-     while (*(++ptr) != ']')
+     BOOL negate_class = FALSE;
+     for (;;)
+       {
+       if (ptr[1] == CHAR_BACKSLASH)
+         {
+         if (ptr[2] == CHAR_E)
+           ptr+= 2;
+         else if (strncmp((const char *)ptr+2,
+                  STR_Q STR_BACKSLASH STR_E, 3) == 0)
+           ptr += 4;
+         else
+           break;
+         }
+       else if (!negate_class && ptr[1] == CHAR_CIRCUMFLEX_ACCENT)
+         {
+         negate_class = TRUE;
+         ptr++;
+         }
+       else break;
+       }
+     /* If the next character is ']', it is a data character that must be
+     skipped, except in JavaScript compatibility mode. */
+     if (ptr[1] == CHAR_RIGHT_SQUARE_BRACKET &&
+         (cd->external_options & PCRE_JAVASCRIPT_COMPAT) == 0)
+       ptr++;
+     while (*(++ptr) != CHAR_RIGHT_SQUARE_BRACKET)
        {
        if (*ptr == 0) return -1;
-       if (*ptr == '\\')
+       if (*ptr == CHAR_BACKSLASH)
          {
-         if (*(++ptr) == 0) return -1;
+         if (*(++ptr) == 0) goto FAIL_EXIT;
-         if (*ptr == 'Q') for (;;)
+         if (*ptr == CHAR_Q) for (;;)
            {
-           while (*(++ptr) != 0 && *ptr != '\\');
+           while (*(++ptr) != 0 && *ptr != CHAR_BACKSLASH) {};
-           if (*ptr == 0) return -1;
+           if (*ptr == 0) goto FAIL_EXIT;
-           if (*(++ptr) == 'E') break;
+           if (*(++ptr) == CHAR_E) break;
            }
          continue;
          }
-Line 968 
 for (; *ptr != 0; ptr++)
+Line 1190 
 for (; *ptr != 0; ptr++)
    /* Skip comments in /x mode */
-   if (xmode && *ptr == '#')
+   if (xmode && *ptr == CHAR_NUMBER_SIGN)
      {
-     while (*(++ptr) != 0 && *ptr != '\n');
+     while (*(++ptr) != 0 && *ptr != CHAR_NL) {};
-     if (*ptr == 0) return -1;
+     if (*ptr == 0) goto FAIL_EXIT;
      continue;
      }
-   /* An opening parens must now be a real metacharacter */
+   /* Check for the special metacharacters */
-   if (*ptr != '(') continue;
+   if (*ptr == CHAR_LEFT_PARENTHESIS)
-   if (ptr[1] != '?' && ptr[1] != '*')
      {
-     count++;
+     int rc = find_parens_sub(&ptr, cd, name, lorn, xmode, count);
-     if (name == NULL && count == lorn) return count;
+     if (rc > 0) return rc;
-     continue;
+     if (*ptr == 0) goto FAIL_EXIT;
      }
-   ptr += 2;
+   else if (*ptr == CHAR_RIGHT_PARENTHESIS)
-   if (*ptr == 'P') ptr++;                      /* Allow optional P */
+     {
+     if (dup_parens && *count < hwm_count) *count = hwm_count;
+     *ptrptr = ptr;
+     return -1;
+     }
-   /* We have to disambiguate (?<! and (?<= from (?<name> */
+   else if (*ptr == CHAR_VERTICAL_LINE && dup_parens)
+     {
+     if (*count > hwm_count) hwm_count = *count;
+     *count = start_count;
+     }
+   }
-   if ((*ptr != '<' || ptr[1] == '!' || ptr[1] == '=') &&
+ FAIL_EXIT:
-        *ptr != '\'')
+ *ptrptr = ptr;
-     continue;
+ return -1;
+ }
+ /*************************************************
+ *       Find forward referenced subpattern       *
+ *************************************************/
+ /* This function scans along a pattern's text looking for capturing
+ subpatterns, and counting them. If it finds a named pattern that matches the
+ name it is given, it returns its number. Alternatively, if the name is NULL, it
+ returns when it reaches a given numbered subpattern. This is used for forward
+ references to subpatterns. We used to be able to start this scan from the
+ current compiling point, using the current count value from cd->bracount, and
+ do it all in a single loop, but the addition of the possibility of duplicate
+ subpattern numbers means that we have to scan from the very start, in order to
+ take account of such duplicates, and to use a recursive function to keep track
+ of the different types of group.
+ Arguments:
+   cd           compile background data
+   name         name to seek, or NULL if seeking a numbered subpattern
+   lorn         name length, or subpattern number if name is NULL
+   xmode        TRUE if we are in /x mode
-   count++;
+ Returns:       the number of the found subpattern, or -1 if not found
+ */
+ static int
+ find_parens(compile_data *cd, const uschar *name, int lorn, BOOL xmode)
+ {
+ uschar *ptr = (uschar *)cd->start_pattern;
+ int count = 0;
+ int rc;
+ /* If the pattern does not start with an opening parenthesis, the first call
+ to find_parens_sub() will scan right to the end (if necessary). However, if it
+ does start with a parenthesis, find_parens_sub() will return when it hits the
+ matching closing parens. That is why we have to have a loop. */
-   if (name == NULL && count == lorn) return count;
+ for (;;)
-   term = *ptr++;
+   {
-   if (term == '<') term = '>';
+   rc = find_parens_sub(&ptr, cd, name, lorn, xmode, &count);
-   thisname = ptr;
+   if (rc > 0 || *ptr++ == 0) break;
-   while (*ptr != term) ptr++;
-   if (name != NULL && lorn == ptr - thisname &&
-       strncmp((const char *)name, (const char *)thisname, lorn) == 0)
-     return count;
    }
- return -1;
+ return rc;
  }
  /*************************************************
  *      Find first significant op code            *
  *************************************************/
-Line 1060 
 for (;;)
+Line 1325 
 for (;;)
      case OP_CALLOUT:
      case OP_CREF:
+     case OP_NCREF:
      case OP_RREF:
+     case OP_NRREF:
      case OP_DEF:
      code += _pcre_OP_lengths[*code];
      break;
-Line 1076 
 for (;;)
+Line 1343 
 for (;;)
  /*************************************************
- *        Find the fixed length of a pattern      *
+ *        Find the fixed length of a branch       *
  *************************************************/
- /* Scan a pattern and compute the fixed length of subject that will match it,
+ /* Scan a branch and compute the fixed length of subject that will match it,
  if the length is fixed. This is needed for dealing with backward assertions.
- In UTF8 mode, the result is in characters rather than bytes.
+ In UTF8 mode, the result is in characters rather than bytes. The branch is
+ temporarily terminated with OP_END when this function is called.
+ This function is called when a backward assertion is encountered, so that if it
+ fails, the error message can point to the correct place in the pattern.
+ However, we cannot do this when the assertion contains subroutine calls,
+ because they can be forward references. We solve this by remembering this case
+ and doing the check at the end; a flag specifies which mode we are running in.
  Arguments:
    code     points to the start of the pattern (the bracket)
    options  the compiling options
+   atend    TRUE if called when the pattern is complete
+   cd       the "compile data" structure
- Returns:   the fixed length, or -1 if there is no fixed length,
+ Returns:   the fixed length,
+              or -1 if there is no fixed length,
               or -2 if \C was encountered
+              or -3 if an OP_RECURSE item was encountered and atend is FALSE
  */
  static int
- find_fixedlength(uschar *code, int options)
+ find_fixedlength(uschar *code, int options, BOOL atend, compile_data *cd)
  {
  int length = -1;
-Line 1105 
 branch, check the length against that of
+Line 1383 
 branch, check the length against that of
  for (;;)
    {
    int d;
+   uschar *ce, *cs;
    register int op = *cc;
    switch (op)
      {
-Line 1112 
 for (;;)
+Line 1391 
 for (;;)
      case OP_BRA:
      case OP_ONCE:
      case OP_COND:
-     d = find_fixedlength(cc + ((op == OP_CBRA)? 2:0), options);
+     d = find_fixedlength(cc + ((op == OP_CBRA)? 2:0), options, atend, cd);
      if (d < 0) return d;
      branchlength += d;
      do cc += GET(cc, 1); while (*cc == OP_ALT);
-Line 1135 
 for (;;)
+Line 1414 
 for (;;)
      branchlength = 0;
      break;
+     /* A true recursion implies not fixed length, but a subroutine call may
+     be OK. If the subroutine is a forward reference, we can't deal with
+     it until the end of the pattern, so return -3. */
+     case OP_RECURSE:
+     if (!atend) return -3;
+     cs = ce = (uschar *)cd->start_code + GET(cc, 1);  /* Start subpattern */
+     do ce += GET(ce, 1); while (*ce == OP_ALT);       /* End subpattern */
+     if (cc > cs && cc < ce) return -1;                /* Recursion */
+     d = find_fixedlength(cs + 2, options, atend, cd);
+     if (d < 0) return d;
+     branchlength += d;
+     cc += 1 + LINK_SIZE;
+     break;
      /* Skip over assertive subpatterns */
      case OP_ASSERT:
-Line 1148 
 for (;;)
+Line 1442 
 for (;;)
      case OP_REVERSE:
      case OP_CREF:
+     case OP_NCREF:
      case OP_RREF:
+     case OP_NRREF:
      case OP_DEF:
      case OP_OPT:
      case OP_CALLOUT:
      case OP_SOD:
      case OP_SOM:
+     case OP_SET_SOM:
      case OP_EOD:
      case OP_EODN:
      case OP_CIRC:
-Line 1171 
 for (;;)
+Line 1468 
 for (;;)
      branchlength++;
      cc += 2;
  #ifdef SUPPORT_UTF8
-     if ((options & PCRE_UTF8) != 0)
+     if ((options & PCRE_UTF8) != 0 && cc[-1] >= 0xc0)
-       {
+       cc += _pcre_utf8_table4[cc[-1] & 0x3f];
-       while ((*cc & 0xc0) == 0x80) cc++;
-       }
  #endif
      break;
-Line 1185 
 for (;;)
+Line 1480 
 for (;;)
      branchlength += GET2(cc,1);
      cc += 4;
  #ifdef SUPPORT_UTF8
-     if ((options & PCRE_UTF8) != 0)
+     if ((options & PCRE_UTF8) != 0 && cc[-1] >= 0xc0)
-       {
+       cc += _pcre_utf8_table4[cc[-1] & 0x3f];
-       while((*cc & 0x80) == 0x80) cc++;
-       }
  #endif
      break;
-Line 1212 
 for (;;)
+Line 1505 
 for (;;)
      case OP_NOT_WORDCHAR:
      case OP_WORDCHAR:
      case OP_ANY:
+     case OP_ALLANY:
      branchlength++;
      cc++;
      break;
-Line 1266 
 for (;;)
+Line 1560 
 for (;;)
  /*************************************************
- *    Scan compiled regex for numbered bracket    *
+ *    Scan compiled regex for specific bracket    *
  *************************************************/
  /* This little function scans through a compiled pattern until it finds a
- capturing bracket with the given number.
+ capturing bracket with the given number, or, if the number is negative, an
+ instance of OP_REVERSE for a lookbehind. The function is global in the C sense
+ so that it can be called from pcre_study() when finding the minimum matching
+ length.
  Arguments:
    code        points to start of expression
    utf8        TRUE in UTF-8 mode
-   number      the required bracket number
+   number      the required bracket number or negative to find a lookbehind
  Returns:      pointer to the opcode for the bracket, or NULL if not found
  */
- static const uschar *
+ const uschar *
- find_bracket(const uschar *code, BOOL utf8, int number)
+ _pcre_find_bracket(const uschar *code, BOOL utf8, int number)
  {
  for (;;)
    {
-Line 1294 
 for (;;)
+Line 1591 
 for (;;)
    if (c == OP_XCLASS) code += GET(code, 1);
+   /* Handle recursion */
+   else if (c == OP_REVERSE)
+     {
+     if (number < 0) return (uschar *)code;
+     code += _pcre_OP_lengths[c];
+     }
    /* Handle capturing bracket */
    else if (c == OP_CBRA)
-Line 1360 
 for (;;)
+Line 1665 
 for (;;)
        if (code[-1] >= 0xc0) code += _pcre_utf8_table4[code[-1] & 0x3f];
        break;
        }
+ #else
+     (void)(utf8);  /* Keep compiler happy by referencing function argument */
  #endif
      }
    }
-Line 1453 
 for (;;)
+Line 1760 
 for (;;)
        if (code[-1] >= 0xc0) code += _pcre_utf8_table4[code[-1] & 0x3f];
        break;
        }
+ #else
+     (void)(utf8);  /* Keep compiler happy by referencing function argument */
  #endif
      }
    }
-Line 1468 
 for (;;)
+Line 1777 
 for (;;)
  can match the empty string or not. It is called from could_be_empty()
  below and from compile_branch() when checking for an unlimited repeat of a
  group that can match nothing. Note that first_significant_code() skips over
- assertions. If we hit an unclosed bracket, we return "empty" - this means we've
+ backward and negative forward assertions when its final argument is TRUE. If we
- struck an inner bracket whose current branch will already have been scanned.
+ hit an unclosed bracket, we return "empty" - this means we've struck an inner
+ bracket whose current branch will already have been scanned.
  Arguments:
    code        points to start of search
    endcode     points to where to stop
    utf8        TRUE if in UTF8 mode
+   cd          contains pointers to tables etc.
  Returns:      TRUE if what is matched could be empty
  */
  static BOOL
- could_be_empty_branch(const uschar *code, const uschar *endcode, BOOL utf8)
+ could_be_empty_branch(const uschar *code, const uschar *endcode, BOOL utf8,
+   compile_data *cd)
  {
  register int c;
  for (code = first_significant_code(code + _pcre_OP_lengths[*code], NULL, 0, TRUE);
-Line 1490 
 for (code = first_significant_code(code
+Line 1802 
 for (code = first_significant_code(code
    const uschar *ccode;
    c = *code;
+   /* Skip over forward assertions; the other assertions are skipped by
+   first_significant_code() with a TRUE final argument. */
+   if (c == OP_ASSERT)
+     {
+     do code += GET(code, 1); while (*code == OP_ALT);
+     c = *code;
+     continue;
+     }
    /* Groups with zero repeats can of course be empty; skip them. */
-   if (c == OP_BRAZERO || c == OP_BRAMINZERO)
+   if (c == OP_BRAZERO || c == OP_BRAMINZERO || c == OP_SKIPZERO)
      {
      code += _pcre_OP_lengths[c];
      do code += GET(code, 1); while (*code == OP_ALT);
      c = *code;
      continue;
      }
+   /* For a recursion/subroutine call, if its end has been reached, which
+   implies a subroutine call, we can scan it. */
+   if (c == OP_RECURSE)
+     {
+     const uschar *scode = cd->start_code + GET(code, 1);
+     if (GET(scode, 1) == 0) return TRUE;    /* Unclosed */
+     do
+       {
+       if (!could_be_empty_branch(scode, endcode, utf8, cd)) return FALSE;
+       scode += GET(scode, 1);
+       }
+     while (*scode == OP_ALT);
+     continue;
+     }
    /* For other groups, scan the branches. */
-Line 1508 
 for (code = first_significant_code(code
+Line 1846 
 for (code = first_significant_code(code
      BOOL empty_branch;
      if (GET(code, 1) == 0) return TRUE;    /* Hit unclosed bracket */
-     /* Scan a closed bracket */
+     /* If a conditional group has only one branch, there is a second, implied,
+     empty branch, so just skip over the conditional, because it could be empty.
+     Otherwise, scan the individual branches of the group. */
-     empty_branch = FALSE;
+     if (c == OP_COND && code[GET(code, 1)] != OP_ALT)
-     do
-       {
-       if (!empty_branch && could_be_empty_branch(code, endcode, utf8))
-         empty_branch = TRUE;
        code += GET(code, 1);
+     else
+       {
+       empty_branch = FALSE;
+       do
+         {
+         if (!empty_branch && could_be_empty_branch(code, endcode, utf8, cd))
+           empty_branch = TRUE;
+         code += GET(code, 1);
+         }
+       while (*code == OP_ALT);
+       if (!empty_branch) return FALSE;   /* All branches are non-empty */
        }
-     while (*code == OP_ALT);
-     if (!empty_branch) return FALSE;   /* All branches are non-empty */
      c = *code;
      continue;
      }
-Line 1579 
 for (code = first_significant_code(code
+Line 1925 
 for (code = first_significant_code(code
      case OP_NOT_WORDCHAR:
      case OP_WORDCHAR:
      case OP_ANY:
+     case OP_ALLANY:
      case OP_ANYBYTE:
      case OP_CHAR:
      case OP_CHARNC:
-Line 1596 
 for (code = first_significant_code(code
+Line 1943 
 for (code = first_significant_code(code
      case OP_TYPEPOSPLUS:
      case OP_TYPEEXACT:
      return FALSE;
      /* These are going to continue, as they may be empty, but we have to
      fudge the length for the \p and \P cases. */
      case OP_TYPESTAR:
      case OP_TYPEMINSTAR:
      case OP_TYPEPOSSTAR:
-Line 1607 
 for (code = first_significant_code(code
+Line 1954 
 for (code = first_significant_code(code
      case OP_TYPEMINQUERY:
      case OP_TYPEPOSQUERY:
      if (code[1] == OP_PROP || code[1] == OP_NOTPROP) code += 2;
      break;
      /* Same for these */
      case OP_TYPEUPTO:
      case OP_TYPEMINUPTO:
      case OP_TYPEPOSUPTO:
-Line 1635 
 for (code = first_significant_code(code
+Line 1982 
 for (code = first_significant_code(code
      case OP_QUERY:
      case OP_MINQUERY:
      case OP_POSQUERY:
+     if (utf8 && code[1] >= 0xc0) code += _pcre_utf8_table4[code[1] & 0x3f];
+     break;
      case OP_UPTO:
      case OP_MINUPTO:
      case OP_POSUPTO:
-     if (utf8) while ((code[2] & 0xc0) == 0x80) code++;
+     if (utf8 && code[3] >= 0xc0) code += _pcre_utf8_table4[code[3] & 0x3f];
      break;
  #endif
+     /* None of the remaining opcodes are required to match a character. */
+     default:
+     break;
      }
    }
-Line 1663 
 Arguments:
+Line 2018 
 Arguments:
    endcode     points to where to stop (current RECURSE item)
    bcptr       points to the chain of current (unclosed) branch starts
    utf8        TRUE if in UTF-8 mode
+   cd          pointers to tables etc
  Returns:      TRUE if what is matched could be empty
  */
  static BOOL
  could_be_empty(const uschar *code, const uschar *endcode, branch_chain *bcptr,
-   BOOL utf8)
+   BOOL utf8, compile_data *cd)
  {
- while (bcptr != NULL && bcptr->current >= code)
+ while (bcptr != NULL && bcptr->current_branch >= code)
    {
-   if (!could_be_empty_branch(bcptr->current, endcode, utf8)) return FALSE;
+   if (!could_be_empty_branch(bcptr->current_branch, endcode, utf8, cd))
+     return FALSE;
    bcptr = bcptr->outer;
    }
  return TRUE;
-Line 1686 
 return TRUE;
+Line 2043 
 return TRUE;
  *************************************************/
  /* This function is called when the sequence "[:" or "[." or "[=" is
- encountered in a character class. It checks whether this is followed by an
+ encountered in a character class. It checks whether this is followed by a
- optional ^ and then a sequence of letters, terminated by a matching ":]" or
+ sequence of characters terminated by a matching ":]" or ".]" or "=]". If we
- ".]" or "=]".
+ reach an unescaped ']' without the special preceding character, return FALSE.
+ Originally, this function only recognized a sequence of letters between the
+ terminators, but it seems that Perl recognizes any sequence of characters,
+ though of course unknown POSIX names are subsequently rejected. Perl gives an
+ "Unknown POSIX class" error for [:f\oo:] for example, where previously PCRE
+ didn't consider this to be a POSIX class. Likewise for [:1234:].
+ The problem in trying to be exactly like Perl is in the handling of escapes. We
+ have to be sure that [abc[:x\]pqr] is *not* treated as containing a POSIX
+ class, but [abc[:x\]pqr:]] is (so that an error can be generated). The code
+ below handles the special case of \], but does not try to do any other escape
+ processing. This makes it different from Perl for cases such as [:l\ower:]
+ where Perl recognizes it as the POSIX class "lower" but PCRE does not recognize
+ "l\ower". This is a lesser evil that not diagnosing bad classes when Perl does,
+ I think.
- Argument:
+ Arguments:
    ptr      pointer to the initial [
    endptr   where to return the end pointer
-   cd       pointer to compile data
  Returns:   TRUE or FALSE
  */
  static BOOL
- check_posix_syntax(const uschar *ptr, const uschar **endptr, compile_data *cd)
+ check_posix_syntax(const uschar *ptr, const uschar **endptr)
  {
  int terminator;          /* Don't combine these lines; the Solaris cc */
  terminator = *(++ptr);   /* compiler warns about "non-constant" initializer. */
- if (*(++ptr) == '^') ptr++;
+ for (++ptr; *ptr != 0; ptr++)
- while ((cd->ctypes[*ptr] & ctype_letter) != 0) ptr++;
- if (*ptr == terminator && ptr[1] == ']')
    {
-   *endptr = ptr;
+   if (*ptr == CHAR_BACKSLASH && ptr[1] == CHAR_RIGHT_SQUARE_BRACKET) ptr++; else
-   return TRUE;
+     {
+     if (*ptr == CHAR_RIGHT_SQUARE_BRACKET) return FALSE;
+     if (*ptr == terminator && ptr[1] == CHAR_RIGHT_SQUARE_BRACKET)
+       {
+       *endptr = ptr;
+       return TRUE;
+       }
+     }
    }
  return FALSE;
  }
-Line 1733 
 Returns:     a value representing the na
+Line 2109 
 Returns:     a value representing the na
  static int
  check_posix_name(const uschar *ptr, int len)
  {
+ const char *pn = posix_names;
  register int yield = 0;
  while (posix_name_lengths[yield] != 0)
    {
    if (len == posix_name_lengths[yield] &&
-     strncmp((const char *)ptr, posix_names[yield], len) == 0) return yield;
+     strncmp((const char *)ptr, pn, len) == 0) return yield;
+   pn += posix_name_lengths[yield] + 1;
    yield++;
    }
  return -1;
-Line 1752 
 return -1;
+Line 2130 
 return -1;
  that is referenced. This means that groups can be replicated for fixed
  repetition simply by copying (because the recursion is allowed to refer to
  earlier groups that are outside the current group). However, when a group is
- optional (i.e. the minimum quantifier is zero), OP_BRAZERO is inserted before
+ optional (i.e. the minimum quantifier is zero), OP_BRAZERO or OP_SKIPZERO is
- it, after it has been compiled. This means that any OP_RECURSE items within it
+ inserted before it, after it has been compiled. This means that any OP_RECURSE
- that refer to the group itself or any contained groups have to have their
+ items within it that refer to the group itself or any contained groups have to
- offsets adjusted. That one of the jobs of this function. Before it is called,
+ have their offsets adjusted. That one of the jobs of this function. Before it
- the partially compiled regex must be temporarily terminated with OP_END.
+ is called, the partially compiled regex must be temporarily terminated with
+ OP_END.
  This function has been extended with the possibility of forward references for
  recursions and subroutine calls. It must also check the list of such references
-Line 1891 
 get_othercase_range(unsigned int *cptr,
+Line 2270 
 get_othercase_range(unsigned int *cptr,
  unsigned int c, othercase, next;
  for (c = *cptr; c <= d; c++)
-   { if ((othercase = _pcre_ucp_othercase(c)) != NOTACHAR) break; }
+   { if ((othercase = UCD_OTHERCASE(c)) != c) break; }
  if (c > d) return FALSE;
-Line 1900 
 next = othercase + 1;
+Line 2279 
 next = othercase + 1;
  for (++c; c <= d; c++)
    {
-   if (_pcre_ucp_othercase(c) != next) break;
+   if (UCD_OTHERCASE(c) != next) break;
    next++;
    }
-Line 1946 
 if ((options & PCRE_EXTENDED) != 0)
+Line 2325 
 if ((options & PCRE_EXTENDED) != 0)
    for (;;)
      {
      while ((cd->ctypes[*ptr] & ctype_space) != 0) ptr++;
-     if (*ptr == '#')
+     if (*ptr == CHAR_NUMBER_SIGN)
        {
        while (*(++ptr) != 0)
          if (IS_NEWLINE(ptr)) { ptr += cd->nllen; break; }
-Line 1958 
 if ((options & PCRE_EXTENDED) != 0)
+Line 2337 
 if ((options & PCRE_EXTENDED) != 0)
  /* If the next item is one that we can handle, get its value. A non-negative
  value is a character, a negative value is an escape value. */
- if (*ptr == '\\')
+ if (*ptr == CHAR_BACKSLASH)
    {
    int temperrorcode = 0;
    next = check_escape(&ptr, &temperrorcode, cd->bracount, options, FALSE);
-Line 1983 
 if ((options & PCRE_EXTENDED) != 0)
+Line 2362 
 if ((options & PCRE_EXTENDED) != 0)
    for (;;)
      {
      while ((cd->ctypes[*ptr] & ctype_space) != 0) ptr++;
-     if (*ptr == '#')
+     if (*ptr == CHAR_NUMBER_SIGN)
        {
        while (*(++ptr) != 0)
          if (IS_NEWLINE(ptr)) { ptr += cd->nllen; break; }
-Line 1994 
 if ((options & PCRE_EXTENDED) != 0)
+Line 2373 
 if ((options & PCRE_EXTENDED) != 0)
  /* If the next thing is itself optional, we have to give up. */
- if (*ptr == '*' || *ptr == '?' || strncmp((char *)ptr, "{0,", 3) == 0)
+ if (*ptr == CHAR_ASTERISK || *ptr == CHAR_QUESTION_MARK ||
-   return FALSE;
+   strncmp((char *)ptr, STR_LEFT_CURLY_BRACKET STR_0 STR_COMMA, 3) == 0)
+     return FALSE;
  /* Now compare the next item with the previous opcode. If the previous is a
  positive single character match, "item" either contains the character or, if
-Line 2010 
 if (next >= 0) switch(op_code)
+Line 2390 
 if (next >= 0) switch(op_code)
    case OP_CHAR:
  #ifdef SUPPORT_UTF8
    if (utf8 && item > 127) { GETCHAR(item, utf8_char); }
+ #else
+   (void)(utf8_char);  /* Keep compiler happy by referencing function argument */
  #endif
    return item != next;
-Line 2028 
 if (next >= 0) switch(op_code)
+Line 2410 
 if (next >= 0) switch(op_code)
      unsigned int othercase;
      if (next < 128) othercase = cd->fcc[next]; else
  #ifdef SUPPORT_UCP
-     othercase = _pcre_ucp_othercase((unsigned int)next);
+     othercase = UCD_OTHERCASE((unsigned int)next);
  #else
      othercase = NOTACHAR;
  #endif
-Line 2041 
 if (next >= 0) switch(op_code)
+Line 2423 
 if (next >= 0) switch(op_code)
    /* For OP_NOT, "item" must be a single-byte character. */
    case OP_NOT:
-   if (next < 0) return FALSE;  /* Not a character */
    if (item == next) return TRUE;
    if ((options & PCRE_CASELESS) == 0) return FALSE;
  #ifdef SUPPORT_UTF8
-Line 2050 
 if (next >= 0) switch(op_code)
+Line 2431 
 if (next >= 0) switch(op_code)
      unsigned int othercase;
      if (next < 128) othercase = cd->fcc[next]; else
  #ifdef SUPPORT_UCP
-     othercase = _pcre_ucp_othercase(next);
+     othercase = UCD_OTHERCASE(next);
  #else
      othercase = NOTACHAR;
  #endif
-Line 2304 
 uschar classbits[32];
+Line 2685 
 uschar classbits[32];
  BOOL class_utf8;
  BOOL utf8 = (options & PCRE_UTF8) != 0;
  uschar *class_utf8data;
+ uschar *class_utf8data_base;
  uschar utf8_char[6];
  #else
  BOOL utf8 = FALSE;
  uschar *utf8_char = NULL;
  #endif
- #ifdef DEBUG
+ #ifdef PCRE_DEBUG
  if (lengthptr != NULL) DPRINTF((">> start branch\n"));
  #endif
-Line 2343 
 req_caseopt = ((options & PCRE_CASELESS)
+Line 2725 
 req_caseopt = ((options & PCRE_CASELESS)
  for (;; ptr++)
    {
    BOOL negate_class;
+   BOOL should_flip_negation;
    BOOL possessive_quantifier;
    BOOL is_quantifier;
    BOOL is_recurse;
-Line 2368 
 for (;; ptr++)
+Line 2751 
 for (;; ptr++)
    if (lengthptr != NULL)
      {
- #ifdef DEBUG
+ #ifdef PCRE_DEBUG
      if (code > cd->hwm) cd->hwm = code;                 /* High water info */
  #endif
      if (code > cd->start_workspace + COMPILE_WORK_SIZE) /* Check for overrun */
-Line 2430 
 for (;; ptr++)
+Line 2813 
 for (;; ptr++)
    if (inescq && c != 0)
      {
-     if (c == '\\' && ptr[1] == 'E')
+     if (c == CHAR_BACKSLASH && ptr[1] == CHAR_E)
        {
        inescq = FALSE;
        ptr++;
-Line 2456 
 for (;; ptr++)
+Line 2839 
 for (;; ptr++)
    /* Fill in length of a previous callout, except when the next thing is
    a quantifier. */
-   is_quantifier = c == '*' || c == '+' || c == '?' ||
+   is_quantifier =
-     (c == '{' && is_counted_repeat(ptr+1));
+     c == CHAR_ASTERISK || c == CHAR_PLUS || c == CHAR_QUESTION_MARK ||
+     (c == CHAR_LEFT_CURLY_BRACKET && is_counted_repeat(ptr+1));
    if (!is_quantifier && previous_callout != NULL &&
         after_manual_callout-- <= 0)
-Line 2472 
 for (;; ptr++)
+Line 2856 
 for (;; ptr++)
    if ((options & PCRE_EXTENDED) != 0)
      {
      if ((cd->ctypes[c] & ctype_space) != 0) continue;
-     if (c == '#')
+     if (c == CHAR_NUMBER_SIGN)
        {
        while (*(++ptr) != 0)
          {
-Line 2497 
 for (;; ptr++)
+Line 2881 
 for (;; ptr++)
      {
      /* ===================================================================*/
      case 0:                        /* The branch terminates at string end */
-     case '|':                      /* or | or ) */
+     case CHAR_VERTICAL_LINE:       /* or | or ) */
-     case ')':
+     case CHAR_RIGHT_PARENTHESIS:
      *firstbyteptr = firstbyte;
      *reqbyteptr = reqbyte;
      *codeptr = code;
-Line 2520 
 for (;; ptr++)
+Line 2904 
 for (;; ptr++)
      /* Handle single-character metacharacters. In multiline mode, ^ disables
      the setting of any following char as a first character. */
-     case '^':
+     case CHAR_CIRCUMFLEX_ACCENT:
      if ((options & PCRE_MULTILINE) != 0)
        {
        if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
-Line 2529 
 for (;; ptr++)
+Line 2913 
 for (;; ptr++)
      *code++ = OP_CIRC;
      break;
-     case '$':
+     case CHAR_DOLLAR_SIGN:
      previous = NULL;
      *code++ = OP_DOLL;
      break;
-Line 2537 
 for (;; ptr++)
+Line 2921 
 for (;; ptr++)
      /* There can never be a first char if '.' is first, whatever happens about
      repeats. The value of reqbyte doesn't change either. */
-     case '.':
+     case CHAR_DOT:
      if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
      zerofirstbyte = firstbyte;
      zeroreqbyte = reqbyte;
      previous = code;
-     *code++ = OP_ANY;
+     *code++ = ((options & PCRE_DOTALL) != 0)? OP_ALLANY: OP_ANY;
      break;
-Line 2557 
 for (;; ptr++)
+Line 2941 
 for (;; ptr++)
      opcode is compiled. It may optionally have a bit map for characters < 256,
      but those above are are explicitly listed afterwards. A flag byte tells
      whether the bitmap is present, and whether this is a negated class or not.
-     */
-     case '[':
+     In JavaScript compatibility mode, an isolated ']' causes an error. In
+     default (Perl) mode, it is treated as a data character. */
+     case CHAR_RIGHT_SQUARE_BRACKET:
+     if ((cd->external_options & PCRE_JAVASCRIPT_COMPAT) != 0)
+       {
+       *errorcodeptr = ERR64;
+       goto FAILED;
+       }
+     goto NORMAL_CHAR;
+     case CHAR_LEFT_SQUARE_BRACKET:
      previous = code;
      /* PCRE supports POSIX class stuff inside a class. Perl gives an error if
      they are encountered at the top level, so we'll do that too. */
-     if ((ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
+     if ((ptr[1] == CHAR_COLON || ptr[1] == CHAR_DOT ||
-         check_posix_syntax(ptr, &tempptr, cd))
+          ptr[1] == CHAR_EQUALS_SIGN) &&
+         check_posix_syntax(ptr, &tempptr))
        {
-       *errorcodeptr = (ptr[1] == ':')? ERR13 : ERR31;
+       *errorcodeptr = (ptr[1] == CHAR_COLON)? ERR13 : ERR31;
        goto FAILED;
        }
-Line 2580 
 for (;; ptr++)
+Line 2975 
 for (;; ptr++)
      for (;;)
        {
        c = *(++ptr);
-       if (c == '\\')
+       if (c == CHAR_BACKSLASH)
          {
-         if (ptr[1] == 'E') ptr++;
+         if (ptr[1] == CHAR_E)
-           else if (strncmp((const char *)ptr+1, "Q\\E", 3) == 0) ptr += 3;
+           ptr++;
-             else break;
+         else if (strncmp((const char *)ptr+1,
+                           STR_Q STR_BACKSLASH STR_E, 3) == 0)
+           ptr += 3;
+         else
+           break;
          }
-       else if (!negate_class && c == '^')
+       else if (!negate_class && c == CHAR_CIRCUMFLEX_ACCENT)
          negate_class = TRUE;
        else break;
        }
+     /* Empty classes are allowed in JavaScript compatibility mode. Otherwise,
+     an initial ']' is taken as a data character -- the code below handles
+     that. In JS mode, [] must always fail, so generate OP_FAIL, whereas
+     [^] must match any character, so generate OP_ALLANY. */
+     if (c == CHAR_RIGHT_SQUARE_BRACKET &&
+         (cd->external_options & PCRE_JAVASCRIPT_COMPAT) != 0)
+       {
+       *code++ = negate_class? OP_ALLANY : OP_FAIL;
+       if (firstbyte == REQ_UNSET) firstbyte = REQ_NONE;
+       zerofirstbyte = firstbyte;
+       break;
+       }
+     /* If a class contains a negative special such as \S, we need to flip the
+     negation flag at the end, so that support for characters > 255 works
+     correctly (they are all included in the class). */
+     should_flip_negation = FALSE;
      /* Keep a count of chars with values < 256 so that we can optimize the case
      of just a single character (as long as it's < 256). However, For higher
      valued UTF-8 characters, we don't yet do any optimization. */
-Line 2608 
 for (;; ptr++)
+Line 3027 
 for (;; ptr++)
  #ifdef SUPPORT_UTF8
      class_utf8 = FALSE;                       /* No chars >= 256 */
      class_utf8data = code + LINK_SIZE + 2;    /* For UTF-8 items */
+     class_utf8data_base = class_utf8data;     /* For resetting in pass 1 */
  #endif
      /* Process characters until ] is reached. By writing this as a "do" it
-Line 2623 
 for (;; ptr++)
+Line 3043 
 for (;; ptr++)
          {                           /* Braces are required because the */
          GETCHARLEN(c, ptr, ptr);    /* macro generates multiple statements */
          }
+       /* In the pre-compile phase, accumulate the length of any UTF-8 extra
+       data and reset the pointer. This is so that very large classes that
+       contain a zillion UTF-8 characters no longer overwrite the work space
+       (which is on the stack). */
+       if (lengthptr != NULL)
+         {
+         *lengthptr += class_utf8data - class_utf8data_base;
+         class_utf8data = class_utf8data_base;
+         }
  #endif
        /* Inside \Q...\E everything is literal except \E */
        if (inescq)
          {
-         if (c == '\\' && ptr[1] == 'E')     /* If we are at \E */
+         if (c == CHAR_BACKSLASH && ptr[1] == CHAR_E)  /* If we are at \E */
            {
            inescq = FALSE;                   /* Reset literal state */
            ptr++;                            /* Skip the 'E' */
-Line 2644 
 for (;; ptr++)
+Line 3076 
 for (;; ptr++)
        [.ch.] and [=ch=] ("collating elements") and fault them, as Perl
 .6 and 5.8 do. */
-       if (c == '[' &&
+       if (c == CHAR_LEFT_SQUARE_BRACKET &&
-           (ptr[1] == ':' || ptr[1] == '.' || ptr[1] == '=') &&
+           (ptr[1] == CHAR_COLON || ptr[1] == CHAR_DOT ||
-           check_posix_syntax(ptr, &tempptr, cd))
+            ptr[1] == CHAR_EQUALS_SIGN) && check_posix_syntax(ptr, &tempptr))
          {
          BOOL local_negate = FALSE;
          int posix_class, taboffset, tabopt;
          register const uschar *cbits = cd->cbits;
          uschar pbits[32];
-         if (ptr[1] != ':')
+         if (ptr[1] != CHAR_COLON)
            {
            *errorcodeptr = ERR31;
            goto FAILED;
            }
          ptr += 2;
-         if (*ptr == '^')
+         if (*ptr == CHAR_CIRCUMFLEX_ACCENT)
            {
            local_negate = TRUE;
+           should_flip_negation = TRUE;  /* Note negative special */
            ptr++;
            }
-Line 2732 
 for (;; ptr++)
+Line 3165 
 for (;; ptr++)
        to 'or' into the one we are building. We assume they have more than one
        character in them, so set class_charcount bigger than one. */
-       if (c == '\\')
+       if (c == CHAR_BACKSLASH)
          {
          c = check_escape(&ptr, errorcodeptr, cd->bracount, options, TRUE);
          if (*errorcodeptr != 0) goto FAILED;
-         if (-c == ESC_b) c = '\b';       /* \b is backslash in a class */
+         if (-c == ESC_b) c = CHAR_BS;       /* \b is backspace in a class */
-         else if (-c == ESC_X) c = 'X';   /* \X is literal X in a class */
+         else if (-c == ESC_X) c = CHAR_X;   /* \X is literal X in a class */
-         else if (-c == ESC_R) c = 'R';   /* \R is literal R in a class */
+         else if (-c == ESC_R) c = CHAR_R;   /* \R is literal R in a class */
          else if (-c == ESC_Q)            /* Handle start of quoted string */
            {
-           if (ptr[1] == '\\' && ptr[2] == 'E')
+           if (ptr[1] == CHAR_BACKSLASH && ptr[2] == CHAR_E)
              {
              ptr += 2; /* avoid empty string */
              }
-Line 2765 
 for (;; ptr++)
+Line 3198 
 for (;; ptr++)
              continue;
              case ESC_D:
+             should_flip_negation = TRUE;
              for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_digit];
              continue;
-Line 2773 
 for (;; ptr++)
+Line 3207 
 for (;; ptr++)
              continue;
              case ESC_W:
+             should_flip_negation = TRUE;
              for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_word];
              continue;
-Line 2782 
 for (;; ptr++)
+Line 3217 
 for (;; ptr++)
              continue;
              case ESC_S:
+             should_flip_negation = TRUE;
              for (c = 0; c < 32; c++) classbits[c] |= ~cbits[c+cbit_space];
              classbits[1] |= 0x08;    /* Perl 5.004 onwards omits VT from \s */
              continue;
-             case ESC_E: /* Perl ignores an orphan \E */
-             continue;
              default:    /* Not recognized; fall through */
              break;      /* Need "default" setting to stop compiler warning. */
              }
-Line 2968 
 for (;; ptr++)
+Line 3401 
 for (;; ptr++)
        entirely. The code for handling \Q and \E is messy. */
        CHECK_RANGE:
-       while (ptr[1] == '\\' && ptr[2] == 'E')
+       while (ptr[1] == CHAR_BACKSLASH && ptr[2] == CHAR_E)
          {
          inescq = FALSE;
          ptr += 2;
-Line 2976 
 for (;; ptr++)
+Line 3409 
 for (;; ptr++)
        oldptr = ptr;
-       if (!inescq && ptr[1] == '-')
+       /* Remember \r or \n */
+       if (c == CHAR_CR || c == CHAR_NL) cd->external_flags |= PCRE_HASCRORLF;
+       /* Check for range */
+       if (!inescq && ptr[1] == CHAR_MINUS)
          {
          int d;
          ptr += 2;
-         while (*ptr == '\\' && ptr[1] == 'E') ptr += 2;
+         while (*ptr == CHAR_BACKSLASH && ptr[1] == CHAR_E) ptr += 2;
          /* If we hit \Q (not followed by \E) at this point, go into escaped
          mode. */
-         while (*ptr == '\\' && ptr[1] == 'Q')
+         while (*ptr == CHAR_BACKSLASH && ptr[1] == CHAR_Q)
            {
            ptr += 2;
-           if (*ptr == '\\' && ptr[1] == 'E') { ptr += 2; continue; }
+           if (*ptr == CHAR_BACKSLASH && ptr[1] == CHAR_E)
+             { ptr += 2; continue; }
            inescq = TRUE;
            break;
            }
-         if (*ptr == 0 || (!inescq && *ptr == ']'))
+         if (*ptr == 0 || (!inescq && *ptr == CHAR_RIGHT_SQUARE_BRACKET))
            {
            ptr = oldptr;
            goto LONE_SINGLE_CHARACTER;
-Line 3012 
 for (;; ptr++)
+Line 3452 
 for (;; ptr++)
          not any of the other escapes. Perl 5.6 treats a hyphen as a literal
          in such circumstances. */
-         if (!inescq && d == '\\')
+         if (!inescq && d == CHAR_BACKSLASH)
            {
            d = check_escape(&ptr, errorcodeptr, cd->bracount, options, TRUE);
            if (*errorcodeptr != 0) goto FAILED;
-           /* \b is backslash; \X is literal X; \R is literal R; any other
+           /* \b is backspace; \X is literal X; \R is literal R; any other
            special means the '-' was literal */
            if (d < 0)
              {
-             if (d == -ESC_b) d = '\b';
+             if (d == -ESC_b) d = CHAR_BS;
-             else if (d == -ESC_X) d = 'X';
+             else if (d == -ESC_X) d = CHAR_X;
-             else if (d == -ESC_R) d = 'R'; else
+             else if (d == -ESC_R) d = CHAR_R; else
                {
                ptr = oldptr;
                goto LONE_SINGLE_CHARACTER;  /* A few lines below */
-Line 3043 
 for (;; ptr++)
+Line 3483 
 for (;; ptr++)
          if (d == c) goto LONE_SINGLE_CHARACTER;  /* A few lines below */
+         /* Remember \r or \n */
+         if (d == CHAR_CR || d == CHAR_NL) cd->external_flags |= PCRE_HASCRORLF;
          /* In UTF-8 mode, if the upper limit is > 255, or > 127 for caseless
          matching, we have to use an XCLASS with extra data items. Caseless
          matching for characters > 127 is available only if UCP support is
-Line 3161 
 for (;; ptr++)
+Line 3605 
 for (;; ptr++)
          if ((options & PCRE_CASELESS) != 0)
            {
            unsigned int othercase;
-           if ((othercase = _pcre_ucp_othercase(c)) != NOTACHAR)
+           if ((othercase = UCD_OTHERCASE(c)) != c)
              {
              *class_utf8data++ = XCL_SINGLE;
              class_utf8data += _pcre_ord2utf8(othercase, class_utf8data);
-Line 3188 
 for (;; ptr++)
+Line 3632 
 for (;; ptr++)
      /* Loop until ']' reached. This "while" is the end of the "do" above. */
-     while ((c = *(++ptr)) != 0 && (c != ']' || inescq));
+     while ((c = *(++ptr)) != 0 && (c != CHAR_RIGHT_SQUARE_BRACKET || inescq));
      if (c == 0)                          /* Missing terminating ']' */
        {
        *errorcodeptr = ERR6;
        goto FAILED;
        }
+ /* This code has been disabled because it would mean that \s counts as
+ an explicit \r or \n reference, and that's not really what is wanted. Now
+ we set the flag only if there is a literal "\r" or "\n" in the class. */
+ #if 0
      /* Remember whether \r or \n are in this class */
      if (negate_class)
        {
-       if ((classbits[1] & 0x24) != 0x24) cd->external_options |= PCRE_HASCRORLF;
+       if ((classbits[1] & 0x24) != 0x24) cd->external_flags |= PCRE_HASCRORLF;
        }
      else
        {
-       if ((classbits[1] & 0x24) != 0) cd->external_options |= PCRE_HASCRORLF;
+       if ((classbits[1] & 0x24) != 0) cd->external_flags |= PCRE_HASCRORLF;
        }
+ #endif
      /* If class_charcount is 1, we saw precisely one character whose value is
      less than 256. As long as there were no characters >= 128 and there was no
      use of \p or \P, in other words, no use of any XCLASS features, we can
      optimize.
      In UTF-8 mode, we can optimize the negative case only if there were no
      characters >= 128 because OP_NOT and the related opcodes like OP_NOTSTAR
      operate on single-bytes only. This is an historical hangover. Maybe one day
-Line 3225 
 for (;; ptr++)
+Line 3677 
 for (;; ptr++)
      reqbyte, save the previous value for reinstating. */
  #ifdef SUPPORT_UTF8
      if (class_charcount == 1 && !class_utf8 &&
        (!utf8 || !negate_class || class_lastchar < 128))
  #else
      if (class_charcount == 1)
-Line 3269 
 for (;; ptr++)
+Line 3721 
 for (;; ptr++)
      zeroreqbyte = reqbyte;
      /* If there are characters with values > 255, we have to compile an
-     extended class, with its own opcode. If there are no characters < 256,
+     extended class, with its own opcode, unless there was a negated special
-     we can omit the bitmap in the actual compiled code. */
+     such as \S in the class, because in that case all characters > 255 are in
+     the class, so any that were explicitly given as well can be ignored. If
+     (when there are explicit characters > 255 that must be listed) there are no
+     characters < 256, we can omit the bitmap in the actual compiled code. */
  #ifdef SUPPORT_UTF8
-     if (class_utf8)
+     if (class_utf8 && !should_flip_negation)
        {
        *class_utf8data++ = XCL_END;    /* Marks the end of extra data */
        *code++ = OP_XCLASS;
-Line 3299 
 for (;; ptr++)
+Line 3754 
 for (;; ptr++)
        }
  #endif
-     /* If there are no characters > 255, negate the 32-byte map if necessary,
+     /* If there are no characters > 255, set the opcode to OP_CLASS or
-     and copy it into the code vector. If this is the first thing in the branch,
+     OP_NCLASS, depending on whether the whole class was negated and whether
-     there can be no first char setting, whatever the repeat count. Any reqbyte
+     there were negative specials such as \S in the class. Then copy the 32-byte
-     setting must remain unchanged after any kind of repeat. */
+     map into the code vector, negating it if necessary. */
+     *code++ = (negate_class == should_flip_negation) ? OP_CLASS : OP_NCLASS;
      if (negate_class)
        {
-       *code++ = OP_NCLASS;
        if (lengthptr == NULL)    /* Save time in the pre-compile phase */
          for (c = 0; c < 32; c++) code[c] = ~classbits[c];
        }
      else
        {
-       *code++ = OP_CLASS;
        memcpy(code, classbits, 32);
        }
      code += 32;
-Line 3323 
 for (;; ptr++)
+Line 3777 
 for (;; ptr++)
      /* Various kinds of repeat; '{' is not necessarily a quantifier, but this
      has been tested above. */
-     case '{':
+     case CHAR_LEFT_CURLY_BRACKET:
      if (!is_quantifier) goto NORMAL_CHAR;
      ptr = read_repeat_counts(ptr+1, &repeat_min, &repeat_max, errorcodeptr);
      if (*errorcodeptr != 0) goto FAILED;
      goto REPEAT;
-     case '*':
+     case CHAR_ASTERISK:
      repeat_min = 0;
      repeat_max = -1;
      goto REPEAT;
-     case '+':
+     case CHAR_PLUS:
      repeat_min = 1;
      repeat_max = -1;
      goto REPEAT;
-     case '?':
+     case CHAR_QUESTION_MARK:
      repeat_min = 0;
      repeat_max = 1;
-Line 3374 
 for (;; ptr++)
+Line 3828 
 for (;; ptr++)
      but if PCRE_UNGREEDY is set, it works the other way round. We change the
      repeat type to the non-default. */
-     if (ptr[1] == '+')
+     if (ptr[1] == CHAR_PLUS)
        {
        repeat_type = 0;                  /* Force greedy */
        possessive_quantifier = TRUE;
        ptr++;
        }
-     else if (ptr[1] == '?')
+     else if (ptr[1] == CHAR_QUESTION_MARK)
        {
        repeat_type = greedy_non_default;
        ptr++;
-Line 3495 
 for (;; ptr++)
+Line 3949 
 for (;; ptr++)
        if (repeat_max == 0) goto END_REPEAT;
+       /*--------------------------------------------------------------------*/
+       /* This code is obsolete from release 8.00; the restriction was finally
+       removed: */
        /* All real repeats make it impossible to handle partial matching (maybe
        one day we will be able to remove this restriction). */
-       if (repeat_max != 1) cd->nopartial = TRUE;
+       /* if (repeat_max != 1) cd->external_flags |= PCRE_NOPARTIAL; */
+       /*--------------------------------------------------------------------*/
        /* Combine the op_type with the repeat_type */
-Line 3645 
 for (;; ptr++)
+Line 4104 
 for (;; ptr++)
          goto END_REPEAT;
          }
+       /*--------------------------------------------------------------------*/
+       /* This code is obsolete from release 8.00; the restriction was finally
+       removed: */
        /* All real repeats make it impossible to handle partial matching (maybe
        one day we will be able to remove this restriction). */
-       if (repeat_max != 1) cd->nopartial = TRUE;
+       /* if (repeat_max != 1) cd->external_flags |= PCRE_NOPARTIAL; */
+       /*--------------------------------------------------------------------*/
        if (repeat_min == 0 && repeat_max == -1)
          *code++ = OP_CRSTAR + repeat_type;
-Line 3706 
 for (;; ptr++)
+Line 4170 
 for (;; ptr++)
        if (repeat_min == 0)
          {
-         /* If the maximum is also zero, we just omit the group from the output
+         /* If the maximum is also zero, we used to just omit the group from the
-         altogether. */
+         output altogether, like this:
-         if (repeat_max == 0)
+         ** if (repeat_max == 0)
-           {
+         **   {
-           code = previous;
+         **   code = previous;
-           goto END_REPEAT;
+         **   goto END_REPEAT;
-           }
+         **   }
+         However, that fails when a group is referenced as a subroutine from
+         elsewhere in the pattern, so now we stick in OP_SKIPZERO in front of it
+         so that it is skipped on execution. As we don't have a list of which
+         groups are referenced, we cannot do this selectively.
+         If the maximum is 1 or unlimited, we just have to stick in the BRAZERO
+         and do no more at this point. However, we do need to adjust any
+         OP_RECURSE calls inside the group that refer to the group itself or any
+         internal or forward referenced group, because the offset is from the
+         start of the whole regex. Temporarily terminate the pattern while doing
+         this. */
-         /* If the maximum is 1 or unlimited, we just have to stick in the
+         if (repeat_max <= 1)    /* Covers 0, 1, and unlimited */
-         BRAZERO and do no more at this point. However, we do need to adjust
-         any OP_RECURSE calls inside the group that refer to the group itself or
-         any internal or forward referenced group, because the offset is from
-         the start of the whole regex. Temporarily terminate the pattern while
-         doing this. */
-         if (repeat_max <= 1)
            {
            *code = OP_END;
            adjust_recurse(previous, 1, utf8, cd, save_hwm);
            memmove(previous+1, previous, len);
            code++;
+           if (repeat_max == 0)
+             {
+             *previous++ = OP_SKIPZERO;
+             goto END_REPEAT;
+             }
            *previous++ = OP_BRAZERO + repeat_type;
            }
-Line 3773 
 for (;; ptr++)
+Line 4247 
 for (;; ptr++)
            {
            /* In the pre-compile phase, we don't actually do the replication. We
            just adjust the length as if we had. Do some paranoid checks for
-           potential integer overflow. */
+           potential integer overflow. The INT64_OR_DOUBLE type is a 64-bit
+           integer type when available, otherwise double. */
            if (lengthptr != NULL)
              {
              int delta = (repeat_min - 1)*length_prevgroup;
-             if ((double)(repeat_min - 1)*(double)length_prevgroup >
+             if ((INT64_OR_DOUBLE)(repeat_min - 1)*
-                                                             (double)INT_MAX ||
+                   (INT64_OR_DOUBLE)length_prevgroup >
+                     (INT64_OR_DOUBLE)INT_MAX ||
                  OFLOW_MAX - *lengthptr < delta)
                {
                *errorcodeptr = ERR20;
-Line 3825 
 for (;; ptr++)
+Line 4301 
 for (;; ptr++)
          just adjust the length as if we had. For each repetition we must add 1
          to the length for BRAZERO and for all but the last repetition we must
          add 2 + 2*LINKSIZE to allow for the nesting that occurs. Do some
-         paranoid checks to avoid integer overflow. */
+         paranoid checks to avoid integer overflow. The INT64_OR_DOUBLE type is
+         a 64-bit integer type when available, otherwise double. */
          if (lengthptr != NULL && repeat_max > 0)
            {
            int delta = repeat_max * (length_prevgroup + 1 + 2 + 2*LINK_SIZE) -
 - 2*LINK_SIZE;   /* Last one doesn't nest */
-           if ((double)repeat_max *
+           if ((INT64_OR_DOUBLE)repeat_max *
-                 (double)(length_prevgroup + 1 + 2 + 2*LINK_SIZE)
+                 (INT64_OR_DOUBLE)(length_prevgroup + 1 + 2 + 2*LINK_SIZE)
-                   > (double)INT_MAX ||
+                   > (INT64_OR_DOUBLE)INT_MAX ||
                OFLOW_MAX - *lengthptr < delta)
              {
              *errorcodeptr = ERR20;
-Line 3910 
 for (;; ptr++)
+Line 4387 
 for (;; ptr++)
            uschar *scode = bracode;
            do
              {
-             if (could_be_empty_branch(scode, ketcode, utf8))
+             if (could_be_empty_branch(scode, ketcode, utf8, cd))
                {
                *bracode += OP_SBRA - OP_BRA;
                break;
-Line 3922 
 for (;; ptr++)
+Line 4399 
 for (;; ptr++)
          }
        }
+     /* If previous is OP_FAIL, it was generated by an empty class [] in
+     JavaScript mode. The other ways in which OP_FAIL can be generated, that is
+     by (*FAIL) or (?!) set previous to NULL, which gives a "nothing to repeat"
+     error above. We can just ignore the repeat in JS case. */
+     else if (*previous == OP_FAIL) goto END_REPEAT;
      /* Else there's some kind of shambles */
      else
-Line 3946 
 for (;; ptr++)
+Line 4430 
 for (;; ptr++)
      if (possessive_quantifier)
        {
        int len;
-       if (*tempcode == OP_EXACT || *tempcode == OP_TYPEEXACT ||
-           *tempcode == OP_NOTEXACT)
+       if (*tempcode == OP_TYPEEXACT)
+         tempcode += _pcre_OP_lengths[*tempcode] +
+           ((tempcode[3] == OP_PROP || tempcode[3] == OP_NOTPROP)? 2 : 0);
+       else if (*tempcode == OP_EXACT || *tempcode == OP_NOTEXACT)
+         {
          tempcode += _pcre_OP_lengths[*tempcode];
+ #ifdef SUPPORT_UTF8
+         if (utf8 && tempcode[-1] >= 0xc0)
+           tempcode += _pcre_utf8_table4[tempcode[-1] & 0x3f];
+ #endif
+         }
        len = code - tempcode;
        if (len > 0) switch (*tempcode)
          {
-Line 3967 
 for (;; ptr++)
+Line 4462 
 for (;; ptr++)
          case OP_NOTQUERY: *tempcode = OP_NOTPOSQUERY; break;
          case OP_NOTUPTO:  *tempcode = OP_NOTPOSUPTO; break;
+         /* Because we are moving code along, we must ensure that any
+         pending recursive references are updated. */
          default:
+         *code = OP_END;
+         adjust_recurse(tempcode, 1 + LINK_SIZE, utf8, cd, save_hwm);
          memmove(tempcode + 1+LINK_SIZE, tempcode, len);
          code += 1 + LINK_SIZE;
          len += 1 + LINK_SIZE;
-Line 3994 
 for (;; ptr++)
+Line 4494 
 for (;; ptr++)
      lookbehind or option setting or condition or all the other extended
      parenthesis forms.  */
-     case '(':
+     case CHAR_LEFT_PARENTHESIS:
      newoptions = options;
      skipbytes = 0;
      bravalue = OP_CBRA;
-Line 4003 
 for (;; ptr++)
+Line 4503 
 for (;; ptr++)
      /* First deal with various "verbs" that can be introduced by '*'. */
-     if (*(++ptr) == '*' && (cd->ctypes[ptr[1]] & ctype_letter) != 0)
+     if (*(++ptr) == CHAR_ASTERISK && (cd->ctypes[ptr[1]] & ctype_letter) != 0)
        {
        int i, namelen;
+       const char *vn = verbnames;
        const uschar *name = ++ptr;
        previous = NULL;
-       while ((cd->ctypes[*++ptr] & ctype_letter) != 0);
+       while ((cd->ctypes[*++ptr] & ctype_letter) != 0) {};
-       if (*ptr == ':')
+       if (*ptr == CHAR_COLON)
          {
          *errorcodeptr = ERR59;   /* Not supported */
          goto FAILED;
          }
-       if (*ptr != ')')
+       if (*ptr != CHAR_RIGHT_PARENTHESIS)
          {
          *errorcodeptr = ERR60;
          goto FAILED;
-Line 4023 
 for (;; ptr++)
+Line 4524 
 for (;; ptr++)
        for (i = 0; i < verbcount; i++)
          {
          if (namelen == verbs[i].len &&
-             strncmp((char *)name, verbs[i].name, namelen) == 0)
+             strncmp((char *)name, vn, namelen) == 0)
            {
-           *code = verbs[i].op;
+           /* Check for open captures before ACCEPT */
-           if (*code++ == OP_ACCEPT) cd->had_accept = TRUE;
+           if (verbs[i].op == OP_ACCEPT)
+             {
+             open_capitem *oc;
+             cd->had_accept = TRUE;
+             for (oc = cd->open_caps; oc != NULL; oc = oc->next)
+               {
+               *code++ = OP_CLOSE;
+               PUT2INC(code, 0, oc->number);
+               }
+             }
+           *code++ = verbs[i].op;
            break;
            }
+         vn += verbs[i].len + 1;
          }
        if (i < verbcount) continue;
        *errorcodeptr = ERR60;
-Line 4038 
 for (;; ptr++)
+Line 4551 
 for (;; ptr++)
      /* Deal with the extended parentheses; all are introduced by '?', and the
      appearance of any of them means that this is not a capturing group. */
-     else if (*ptr == '?')
+     else if (*ptr == CHAR_QUESTION_MARK)
        {
        int i, set, unset, namelen;
        int *optset;
-Line 4047 
 for (;; ptr++)
+Line 4560 
 for (;; ptr++)
        switch (*(++ptr))
          {
-         case '#':                 /* Comment; skip to ket */
+         case CHAR_NUMBER_SIGN:                 /* Comment; skip to ket */
          ptr++;
-         while (*ptr != 0 && *ptr != ')') ptr++;
+         while (*ptr != 0 && *ptr != CHAR_RIGHT_PARENTHESIS) ptr++;
          if (*ptr == 0)
            {
            *errorcodeptr = ERR18;
-Line 4059 
 for (;; ptr++)
+Line 4572 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
-         case '|':                 /* Reset capture count for each branch */
+         case CHAR_VERTICAL_LINE:  /* Reset capture count for each branch */
          reset_bracount = TRUE;
          /* Fall through */
          /* ------------------------------------------------------------ */
-         case ':':                 /* Non-capturing bracket */
+         case CHAR_COLON:          /* Non-capturing bracket */
          bravalue = OP_BRA;
          ptr++;
          break;
          /* ------------------------------------------------------------ */
-         case '(':
+         case CHAR_LEFT_PARENTHESIS:
          bravalue = OP_COND;       /* Conditional group */
          /* A condition can be an assertion, a number (referring to a numbered
-Line 4091 
 for (;; ptr++)
+Line 4604 
 for (;; ptr++)
          the switch. This will take control down to where bracketed groups,
          including assertions, are processed. */
-         if (ptr[1] == '?' && (ptr[2] == '=' || ptr[2] == '!' || ptr[2] == '<'))
+         if (ptr[1] == CHAR_QUESTION_MARK && (ptr[2] == CHAR_EQUALS_SIGN ||
+             ptr[2] == CHAR_EXCLAMATION_MARK || ptr[2] == CHAR_LESS_THAN_SIGN))
            break;
          /* Most other conditions use OP_CREF (a couple change to OP_RREF
-Line 4103 
 for (;; ptr++)
+Line 4617 
 for (;; ptr++)
          /* Check for a test for recursion in a named group. */
-         if (ptr[1] == 'R' && ptr[2] == '&')
+         if (ptr[1] == CHAR_R && ptr[2] == CHAR_AMPERSAND)
            {
            terminator = -1;
            ptr += 2;
-Line 4113 
 for (;; ptr++)
+Line 4627 
 for (;; ptr++)
          /* Check for a test for a named group's having been set, using the Perl
          syntax (?(<name>) or (?('name') */
-         else if (ptr[1] == '<')
+         else if (ptr[1] == CHAR_LESS_THAN_SIGN)
            {
-           terminator = '>';
+           terminator = CHAR_GREATER_THAN_SIGN;
            ptr++;
            }
-         else if (ptr[1] == '\'')
+         else if (ptr[1] == CHAR_APOSTROPHE)
            {
-           terminator = '\'';
+           terminator = CHAR_APOSTROPHE;
            ptr++;
            }
          else
            {
            terminator = 0;
-           if (ptr[1] == '-' || ptr[1] == '+') refsign = *(++ptr);
+           if (ptr[1] == CHAR_MINUS || ptr[1] == CHAR_PLUS) refsign = *(++ptr);
            }
          /* We now expect to read a name; any thing else is an error */
-Line 4146 
 for (;; ptr++)
+Line 4660 
 for (;; ptr++)
            {
            if (recno >= 0)
              recno = ((digitab[*ptr] & ctype_digit) != 0)?
-               recno * 10 + *ptr - '0' : -1;
+               recno * 10 + *ptr - CHAR_0 : -1;
            ptr++;
            }
          namelen = ptr - name;
-         if ((terminator > 0 && *ptr++ != terminator) || *ptr++ != ')')
+         if ((terminator > 0 && *ptr++ != terminator) ||
+             *ptr++ != CHAR_RIGHT_PARENTHESIS)
            {
            ptr--;      /* Error offset */
            *errorcodeptr = ERR26;
-Line 4173 
 for (;; ptr++)
+Line 4688 
 for (;; ptr++)
              *errorcodeptr = ERR58;
              goto FAILED;
              }
-           if (refsign == '-')
+           recno = (refsign == CHAR_MINUS)?
+             cd->bracount - recno + 1 : recno +cd->bracount;
+           if (recno <= 0 || recno > cd->final_bracount)
              {
-             recno = cd->bracount - recno + 1;
+             *errorcodeptr = ERR15;
-             if (recno <= 0)
+             goto FAILED;
-               {
-               *errorcodeptr = ERR15;
-               goto FAILED;
-               }
              }
-           else recno += cd->bracount;
            PUT2(code, 2+LINK_SIZE, recno);
            break;
            }
          /* Otherwise (did not start with "+" or "-"), start by looking for the
-         name. */
+         name. If we find a name, add one to the opcode to change OP_CREF or
+         OP_RREF into OP_NCREF or OP_NRREF. These behave exactly the same,
+         except they record that the reference was originally to a name. The
+         information is used to check duplicate names. */
          slot = cd->name_table;
          for (i = 0; i < cd->names_found; i++)
-Line 4203 
 for (;; ptr++)
+Line 4718 
 for (;; ptr++)
            {
            recno = GET2(slot, 0);
            PUT2(code, 2+LINK_SIZE, recno);
+           code[1+LINK_SIZE]++;
            }
          /* Search the pattern for a forward reference */
-         else if ((i = find_parens(ptr, cd->bracount, name, namelen,
+         else if ((i = find_parens(cd, name, namelen,
                          (options & PCRE_EXTENDED) != 0)) > 0)
            {
            PUT2(code, 2+LINK_SIZE, i);
+           code[1+LINK_SIZE]++;
            }
          /* If terminator == 0 it means that the name followed directly after
-Line 4228 
 for (;; ptr++)
+Line 4745 
 for (;; ptr++)
          /* Check for (?(R) for recursion. Allow digits after R to specify a
          specific group number. */
-         else if (*name == 'R')
+         else if (*name == CHAR_R)
            {
            recno = 0;
            for (i = 1; i < namelen; i++)
-Line 4238 
 for (;; ptr++)
+Line 4755 
 for (;; ptr++)
                *errorcodeptr = ERR15;
                goto FAILED;
                }
-             recno = recno * 10 + name[i] - '0';
+             recno = recno * 10 + name[i] - CHAR_0;
              }
            if (recno == 0) recno = RREF_ANY;
            code[1+LINK_SIZE] = OP_RREF;      /* Change test type */
-Line 4248 
 for (;; ptr++)
+Line 4765 
 for (;; ptr++)
          /* Similarly, check for the (?(DEFINE) "condition", which is always
          false. */
-         else if (namelen == 6 && strncmp((char *)name, "DEFINE", 6) == 0)
+         else if (namelen == 6 && strncmp((char *)name, STRING_DEFINE, 6) == 0)
            {
            code[1+LINK_SIZE] = OP_DEF;
            skipbytes = 1;
            }
-         /* Check for the "name" actually being a subpattern number. */
+         /* Check for the "name" actually being a subpattern number. We are
+         in the second pass here, so final_bracount is set. */
-         else if (recno > 0)
+         else if (recno > 0 && recno <= cd->final_bracount)
            {
            PUT2(code, 2+LINK_SIZE, recno);
            }
-Line 4272 
 for (;; ptr++)
+Line 4790 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
-         case '=':                 /* Positive lookahead */
+         case CHAR_EQUALS_SIGN:                 /* Positive lookahead */
          bravalue = OP_ASSERT;
          ptr++;
          break;
          /* ------------------------------------------------------------ */
-         case '!':                 /* Negative lookahead */
+         case CHAR_EXCLAMATION_MARK:            /* Negative lookahead */
          ptr++;
-         if (*ptr == ')')          /* Optimize (?!) */
+         if (*ptr == CHAR_RIGHT_PARENTHESIS)    /* Optimize (?!) */
            {
            *code++ = OP_FAIL;
            previous = NULL;
-Line 4292 
 for (;; ptr++)
+Line 4810 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
-         case '<':                 /* Lookbehind or named define */
+         case CHAR_LESS_THAN_SIGN:              /* Lookbehind or named define */
          switch (ptr[1])
            {
-           case '=':               /* Positive lookbehind */
+           case CHAR_EQUALS_SIGN:               /* Positive lookbehind */
            bravalue = OP_ASSERTBACK;
            ptr += 2;
            break;
-           case '!':               /* Negative lookbehind */
+           case CHAR_EXCLAMATION_MARK:          /* Negative lookbehind */
            bravalue = OP_ASSERTBACK_NOT;
            ptr += 2;
            break;
-Line 4315 
 for (;; ptr++)
+Line 4833 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
-         case '>':                 /* One-time brackets */
+         case CHAR_GREATER_THAN_SIGN:           /* One-time brackets */
          bravalue = OP_ONCE;
          ptr++;
          break;
          /* ------------------------------------------------------------ */
-         case 'C':                 /* Callout - may be followed by digits; */
+         case CHAR_C:                 /* Callout - may be followed by digits; */
          previous_callout = code;  /* Save for later completion */
          after_manual_callout = 1; /* Skip one item before completing */
          *code++ = OP_CALLOUT;
            {
            int n = 0;
            while ((digitab[*(++ptr)] & ctype_digit) != 0)
-             n = n * 10 + *ptr - '0';
+             n = n * 10 + *ptr - CHAR_0;
-           if (*ptr != ')')
+           if (*ptr != CHAR_RIGHT_PARENTHESIS)
              {
              *errorcodeptr = ERR39;
              goto FAILED;
-Line 4350 
 for (;; ptr++)
+Line 4868 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
-         case 'P':                 /* Python-style named subpattern handling */
+         case CHAR_P:              /* Python-style named subpattern handling */
-         if (*(++ptr) == '=' || *ptr == '>')  /* Reference or recursion */
+         if (*(++ptr) == CHAR_EQUALS_SIGN ||
+             *ptr == CHAR_GREATER_THAN_SIGN)  /* Reference or recursion */
            {
-           is_recurse = *ptr == '>';
+           is_recurse = *ptr == CHAR_GREATER_THAN_SIGN;
-           terminator = ')';
+           terminator = CHAR_RIGHT_PARENTHESIS;
            goto NAMED_REF_OR_RECURSE;
            }
-         else if (*ptr != '<')    /* Test for Python-style definition */
+         else if (*ptr != CHAR_LESS_THAN_SIGN)  /* Test for Python-style defn */
            {
            *errorcodeptr = ERR41;
            goto FAILED;
-Line 4367 
 for (;; ptr++)
+Line 4886 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
          DEFINE_NAME:    /* Come here from (?< handling */
-         case '\'':
+         case CHAR_APOSTROPHE:
            {
-           terminator = (*ptr == '<')? '>' : '\'';
+           terminator = (*ptr == CHAR_LESS_THAN_SIGN)?
+             CHAR_GREATER_THAN_SIGN : CHAR_APOSTROPHE;
            name = ++ptr;
            while ((cd->ctypes[*ptr] & ctype_word) != 0) ptr++;
-Line 4400 
 for (;; ptr++)
+Line 4920 
 for (;; ptr++)
                }
              }
-           /* In the real compile, create the entry in the table */
+           /* In the real compile, create the entry in the table, maintaining
+           alphabetical order. Duplicate names for different numbers are
+           permitted only if PCRE_DUPNAMES is set. Duplicate names for the same
+           number are always OK. (An existing number can be re-used if (?|
+           appears in the pattern.) In either event, a duplicate name results in
+           a duplicate entry in the table, even if the number is the same. This
+           is because the number of names, and hence the table size, is computed
+           in the pre-compile, and it affects various numbers and pointers which
+           would all have to be modified, and the compiled code moved down, if
+           duplicates with the same number were omitted from the table. This
+           doesn't seem worth the hassle. However, *different* names for the
+           same number are not permitted. */
            else
              {
+             BOOL dupname = FALSE;
              slot = cd->name_table;
              for (i = 0; i < cd->names_found; i++)
                {
                int crc = memcmp(name, slot+2, namelen);
-Line 4412 
 for (;; ptr++)
+Line 4945 
 for (;; ptr++)
                  {
                  if (slot[2+namelen] == 0)
                    {
-                   if ((options & PCRE_DUPNAMES) == 0)
+                   if (GET2(slot, 0) != cd->bracount + 1 &&
+                       (options & PCRE_DUPNAMES) == 0)
                      {
                      *errorcodeptr = ERR43;
                      goto FAILED;
                      }
+                   else dupname = TRUE;
                    }
-                 else crc = -1;      /* Current name is substring */
+                 else crc = -1;      /* Current name is a substring */
                  }
+               /* Make space in the table and break the loop for an earlier
+               name. For a duplicate or later name, carry on. We do this for
+               duplicates so that in the simple case (when ?(| is not used) they
+               are in order of their numbers. */
                if (crc < 0)
                  {
                  memmove(slot + cd->name_entry_size, slot,
                    (cd->names_found - i) * cd->name_entry_size);
                  break;
                  }
+               /* Continue the loop for a later or duplicate name */
                slot += cd->name_entry_size;
                }
+             /* For non-duplicate names, check for a duplicate number before
+             adding the new name. */
+             if (!dupname)
+               {
+               uschar *cslot = cd->name_table;
+               for (i = 0; i < cd->names_found; i++)
+                 {
+                 if (cslot != slot)
+                   {
+                   if (GET2(cslot, 0) == cd->bracount + 1)
+                     {
+                     *errorcodeptr = ERR65;
+                     goto FAILED;
+                     }
+                   }
+                 else i--;
+                 cslot += cd->name_entry_size;
+                 }
+               }
              PUT2(slot, 0, cd->bracount + 1);
              memcpy(slot + 2, name, namelen);
              slot[2+namelen] = 0;
              }
            }
-         /* In both cases, count the number of names we've encountered. */
+         /* In both pre-compile and compile, count the number of names we've
+         encountered. */
-         ptr++;                    /* Move past > or ' */
          cd->names_found++;
+         ptr++;                    /* Move past > or ' */
          goto NUMBERED_GROUP;
          /* ------------------------------------------------------------ */
-         case '&':                 /* Perl recursion/subroutine syntax */
+         case CHAR_AMPERSAND:            /* Perl recursion/subroutine syntax */
-         terminator = ')';
+         terminator = CHAR_RIGHT_PARENTHESIS;
          is_recurse = TRUE;
          /* Fall through */
          /* We come here from the Python syntax above that handles both
          references (?P=name) and recursion (?P>name), as well as falling
-         through from the Perl recursion syntax (?&name). */
+         through from the Perl recursion syntax (?&name). We also come here from
+         the Perl \k<name> or \k'name' back reference syntax and the \k{name}
+         .NET syntax, and the Oniguruma \g<...> and \g'...' subroutine syntax. */
          NAMED_REF_OR_RECURSE:
          name = ++ptr;
-Line 4462 
 for (;; ptr++)
+Line 5030 
 for (;; ptr++)
          if (lengthptr != NULL)
            {
+           if (namelen == 0)
+             {
+             *errorcodeptr = ERR62;
+             goto FAILED;
+             }
            if (*ptr != terminator)
              {
              *errorcodeptr = ERR42;
-Line 4475 
 for (;; ptr++)
+Line 5048 
 for (;; ptr++)
            recno = 0;
            }
-         /* In the real compile, seek the name in the table */
+         /* In the real compile, seek the name in the table. We check the name
+         first, and then check that we have reached the end of the name in the
+         table. That way, if the name that is longer than any in the table,
+         the comparison will fail without reading beyond the table entry. */
          else
            {
            slot = cd->name_table;
            for (i = 0; i < cd->names_found; i++)
              {
-             if (strncmp((char *)name, (char *)slot+2, namelen) == 0) break;
+             if (strncmp((char *)name, (char *)slot+2, namelen) == 0 &&
+                 slot[2+namelen] == 0)
+               break;
              slot += cd->name_entry_size;
              }
-Line 4491 
 for (;; ptr++)
+Line 5069 
 for (;; ptr++)
              recno = GET2(slot, 0);
              }
            else if ((recno =                /* Forward back reference */
-                     find_parens(ptr, cd->bracount, name, namelen,
+                     find_parens(cd, name, namelen,
                        (options & PCRE_EXTENDED) != 0)) <= 0)
              {
              *errorcodeptr = ERR15;
-Line 4507 
 for (;; ptr++)
+Line 5085 
 for (;; ptr++)
          /* ------------------------------------------------------------ */
-         case 'R':                 /* Recursion */
+         case CHAR_R:              /* Recursion */
          ptr++;                    /* Same as (?0)      */
          /* Fall through */
          /* ------------------------------------------------------------ */
-         case '-': case '+':
+         case CHAR_MINUS: case CHAR_PLUS:  /* Recursion or subroutine */
-         case '0': case '1': case '2': case '3': case '4':   /* Recursion or */
+         case CHAR_0: case CHAR_1: case CHAR_2: case CHAR_3: case CHAR_4:
-         case '5': case '6': case '7': case '8': case '9':   /* subroutine */
+         case CHAR_5: case CHAR_6: case CHAR_7: case CHAR_8: case CHAR_9:
            {
            const uschar *called;
+           terminator = CHAR_RIGHT_PARENTHESIS;
-           if ((refsign = *ptr) == '+') ptr++;
+           /* Come here from the \g<...> and \g'...' code (Oniguruma
-           else if (refsign == '-')
+           compatibility). However, the syntax has been checked to ensure that
+           the ... are a (signed) number, so that neither ERR63 nor ERR29 will
+           be called on this path, nor with the jump to OTHER_CHAR_AFTER_QUERY
+           ever be taken. */
+           HANDLE_NUMERICAL_RECURSION:
+           if ((refsign = *ptr) == CHAR_PLUS)
+             {
+             ptr++;
+             if ((digitab[*ptr] & ctype_digit) == 0)
+               {
+               *errorcodeptr = ERR63;
+               goto FAILED;
+               }
+             }
+           else if (refsign == CHAR_MINUS)
              {
              if ((digitab[ptr[1]] & ctype_digit) == 0)
                goto OTHER_CHAR_AFTER_QUERY;
-Line 4529 
 for (;; ptr++)
+Line 5124 
 for (;; ptr++)
            recno = 0;
            while((digitab[*ptr] & ctype_digit) != 0)
-             recno = recno * 10 + *ptr++ - '0';
+             recno = recno * 10 + *ptr++ - CHAR_0;
-           if (*ptr != ')')
+           if (*ptr != terminator)
              {
              *errorcodeptr = ERR29;
              goto FAILED;
              }
-           if (refsign == '-')
+           if (refsign == CHAR_MINUS)
              {
              if (recno == 0)
                {
-Line 4551 
 for (;; ptr++)
+Line 5146 
 for (;; ptr++)
                goto FAILED;
                }
              }
-           else if (refsign == '+')
+           else if (refsign == CHAR_PLUS)
              {
              if (recno == 0)
                {
-Line 4578 
 for (;; ptr++)
+Line 5173 
 for (;; ptr++)
            if (lengthptr == NULL)
              {
              *code = OP_END;
-             if (recno != 0) called = find_bracket(cd->start_code, utf8, recno);
+             if (recno != 0)
+               called = _pcre_find_bracket(cd->start_code, utf8, recno);
              /* Forward reference */
              if (called == NULL)
                {
-               if (find_parens(ptr, cd->bracount, NULL, recno,
+               if (find_parens(cd, NULL, recno,
-                    (options & PCRE_EXTENDED) != 0) < 0)
+                     (options & PCRE_EXTENDED) != 0) < 0)
                  {
                  *errorcodeptr = ERR15;
                  goto FAILED;
                  }
+               /* Fudge the value of "called" so that when it is inserted as an
+               offset below, what it actually inserted is the reference number
+               of the group. */
                called = cd->start_code + recno;
                PUTINC(cd->hwm, 0, code + 2 + LINK_SIZE - cd->start_code);
                }
-Line 4599 
 for (;; ptr++)
+Line 5200 
 for (;; ptr++)
              recursion that could loop for ever, and diagnose that case. */
              else if (GET(called, 1) == 0 &&
-                      could_be_empty(called, code, bcptr, utf8))
+                      could_be_empty(called, code, bcptr, utf8, cd))
                {
                *errorcodeptr = ERR40;
                goto FAILED;
-Line 4637 
 for (;; ptr++)
+Line 5238 
 for (;; ptr++)
          set = unset = 0;
          optset = &set;
-         while (*ptr != ')' && *ptr != ':')
+         while (*ptr != CHAR_RIGHT_PARENTHESIS && *ptr != CHAR_COLON)
            {
            switch (*ptr++)
              {
-             case '-': optset = &unset; break;
+             case CHAR_MINUS: optset = &unset; break;
-             case 'J':    /* Record that it changed in the external options */
+             case CHAR_J:    /* Record that it changed in the external options */
              *optset |= PCRE_DUPNAMES;
-             cd->external_options |= PCRE_JCHANGED;
+             cd->external_flags |= PCRE_JCHANGED;
              break;
-             case 'i': *optset |= PCRE_CASELESS; break;
+             case CHAR_i: *optset |= PCRE_CASELESS; break;
-             case 'm': *optset |= PCRE_MULTILINE; break;
+             case CHAR_m: *optset |= PCRE_MULTILINE; break;
-             case 's': *optset |= PCRE_DOTALL; break;
+             case CHAR_s: *optset |= PCRE_DOTALL; break;
-             case 'x': *optset |= PCRE_EXTENDED; break;
+             case CHAR_x: *optset |= PCRE_EXTENDED; break;
-             case 'U': *optset |= PCRE_UNGREEDY; break;
+             case CHAR_U: *optset |= PCRE_UNGREEDY; break;
-             case 'X': *optset |= PCRE_EXTRA; break;
+             case CHAR_X: *optset |= PCRE_EXTRA; break;
              default:  *errorcodeptr = ERR12;
                        ptr--;    /* Correct the offset */
-Line 4684 
 for (;; ptr++)
+Line 5285 
 for (;; ptr++)
          both phases.
          If we are not at the pattern start, compile code to change the ims
-         options if this setting actually changes any of them. We also pass the
+         options if this setting actually changes any of them, and reset the
-         new setting back so that it can be put at the start of any following
+         greedy defaults and the case value for firstbyte and reqbyte. */
-         branches, and when this group ends (if we are in a group), a resetting
-         item can be compiled. */
-         if (*ptr == ')')
+         if (*ptr == CHAR_RIGHT_PARENTHESIS)
            {
            if (code == cd->start_code + 1 + LINK_SIZE &&
                 (lengthptr == NULL || *lengthptr == 2 + 2*LINK_SIZE))
              {
              cd->external_options = newoptions;
-             options = newoptions;
              }
-          else
+           else
              {
              if ((options & PCRE_IMS) != (newoptions & PCRE_IMS))
                {
                *code++ = OP_OPT;
                *code++ = newoptions & PCRE_IMS;
                }
-             /* Change options at this level, and pass them back for use
-             in subsequent branches. Reset the greedy defaults and the case
-             value for firstbyte and reqbyte. */
-             *optionsptr = options = newoptions;
              greedy_default = ((newoptions & PCRE_UNGREEDY) != 0);
              greedy_non_default = greedy_default ^ 1;
-             req_caseopt = ((options & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;
+             req_caseopt = ((newoptions & PCRE_CASELESS) != 0)? REQ_CASELESS : 0;
              }
+           /* Change options at this level, and pass them back for use
+           in subsequent branches. When not at the start of the pattern, this
+           information is also necessary so that a resetting item can be
+           compiled at the end of a group (if we are in a group). */
+           *optionsptr = options = newoptions;
            previous = NULL;       /* This item can't be repeated */
            continue;              /* It is complete */
            }
-Line 4830 
 for (;; ptr++)
+Line 5428 
 for (;; ptr++)
      /* Error if hit end of pattern */
-     if (*ptr != ')')
+     if (*ptr != CHAR_RIGHT_PARENTHESIS)
        {
        *errorcodeptr = ERR14;
        goto FAILED;
-Line 4928 
 for (;; ptr++)
+Line 5526 
 for (;; ptr++)
      We can test for values between ESC_b and ESC_Z for the latter; this may
      have to change if any new ones are ever created. */
-     case '\\':
+     case CHAR_BACKSLASH:
      tempptr = ptr;
      c = check_escape(&ptr, errorcodeptr, cd->bracount, options, FALSE);
      if (*errorcodeptr != 0) goto FAILED;
-Line 4937 
 for (;; ptr++)
+Line 5535 
 for (;; ptr++)
        {
        if (-c == ESC_Q)            /* Handle start of quoted string */
          {
-         if (ptr[1] == '\\' && ptr[2] == 'E') ptr += 2; /* avoid empty string */
+         if (ptr[1] == CHAR_BACKSLASH && ptr[2] == CHAR_E)
-           else inescq = TRUE;
+           ptr += 2;               /* avoid empty string */
+             else inescq = TRUE;
          continue;
          }
-Line 4955 
 for (;; ptr++)
+Line 5554 
 for (;; ptr++)
        zerofirstbyte = firstbyte;
        zeroreqbyte = reqbyte;
+       /* \g<name> or \g'name' is a subroutine call by name and \g<n> or \g'n'
+       is a subroutine call by number (Oniguruma syntax). In fact, the value
+       -ESC_g is returned only for these cases. So we don't need to check for <
+       or ' if the value is -ESC_g. For the Perl syntax \g{n} the value is
+       -ESC_REF+n, and for the Perl syntax \g{name} the result is -ESC_k (as
+       that is a synonym for a named back reference). */
+       if (-c == ESC_g)
+         {
+         const uschar *p;
+         save_hwm = cd->hwm;   /* Normally this is set when '(' is read */
+         terminator = (*(++ptr) == CHAR_LESS_THAN_SIGN)?
+           CHAR_GREATER_THAN_SIGN : CHAR_APOSTROPHE;
+         /* These two statements stop the compiler for warning about possibly
+         unset variables caused by the jump to HANDLE_NUMERICAL_RECURSION. In
+         fact, because we actually check for a number below, the paths that
+         would actually be in error are never taken. */
+         skipbytes = 0;
+         reset_bracount = FALSE;
+         /* Test for a name */
+         if (ptr[1] != CHAR_PLUS && ptr[1] != CHAR_MINUS)
+           {
+           BOOL isnumber = TRUE;
+           for (p = ptr + 1; *p != 0 && *p != terminator; p++)
+             {
+             if ((cd->ctypes[*p] & ctype_digit) == 0) isnumber = FALSE;
+             if ((cd->ctypes[*p] & ctype_word) == 0) break;
+             }
+           if (*p != terminator)
+             {
+             *errorcodeptr = ERR57;
+             break;
+             }
+           if (isnumber)
+             {
+             ptr++;
+             goto HANDLE_NUMERICAL_RECURSION;
+             }
+           is_recurse = TRUE;
+           goto NAMED_REF_OR_RECURSE;
+           }
+         /* Test a signed number in angle brackets or quotes. */
+         p = ptr + 2;
+         while ((digitab[*p] & ctype_digit) != 0) p++;
+         if (*p != terminator)
+           {
+           *errorcodeptr = ERR57;
+           break;
+           }
+         ptr++;
+         goto HANDLE_NUMERICAL_RECURSION;
+         }
        /* \k<name> or \k'name' is a back reference by name (Perl syntax).
        We also support \k{name} (.NET syntax) */
-       if (-c == ESC_k && (ptr[1] == '<' || ptr[1] == '\'' || ptr[1] == '{'))
+       if (-c == ESC_k && (ptr[1] == CHAR_LESS_THAN_SIGN ||
+           ptr[1] == CHAR_APOSTROPHE || ptr[1] == CHAR_LEFT_CURLY_BRACKET))
          {
          is_recurse = FALSE;
-         terminator = (*(++ptr) == '<')? '>' : (*ptr == '\'')? '\'' : '}';
+         terminator = (*(++ptr) == CHAR_LESS_THAN_SIGN)?
+           CHAR_GREATER_THAN_SIGN : (*ptr == CHAR_APOSTROPHE)?
+           CHAR_APOSTROPHE : CHAR_RIGHT_CURLY_BRACKET;
          goto NAMED_REF_OR_RECURSE;
          }
-Line 4971 
 for (;; ptr++)
+Line 5632 
 for (;; ptr++)
        if (-c >= ESC_REF)
          {
+         open_capitem *oc;
          recno = -c - ESC_REF;
          HANDLE_REFERENCE:    /* Come here from named backref handling */
-Line 4980 
 for (;; ptr++)
+Line 5642 
 for (;; ptr++)
          PUT2INC(code, 0, recno);
          cd->backref_map |= (recno < 32)? (1 << recno) : 1;
          if (recno > cd->top_backref) cd->top_backref = recno;
+         /* Check to see if this back reference is recursive, that it, it
+         is inside the group that it references. A flag is set so that the
+         group can be made atomic. */
+         for (oc = cd->open_caps; oc != NULL; oc = oc->next)
+           {
+           if (oc->number == recno)
+             {
+             oc->flag = TRUE;
+             break;
+             }
+           }
          }
        /* So are Unicode property matches, if supported. */
-Line 5061 
 for (;; ptr++)
+Line 5736 
 for (;; ptr++)
      previous = code;
      *code++ = ((options & PCRE_CASELESS) != 0)? OP_CHARNC : OP_CHAR;
      for (c = 0; c < mclength; c++) *code++ = mcbuffer[c];
      /* Remember if \r or \n were seen */
-     if (mcbuffer[0] == '\r' || mcbuffer[0] == '\n')
+     if (mcbuffer[0] == CHAR_CR || mcbuffer[0] == CHAR_NL)
-       cd->external_options |= PCRE_HASCRORLF;
+       cd->external_flags |= PCRE_HASCRORLF;
      /* Set the first and required bytes appropriately. If no previous first
      byte, set it from this character, but revert to none on a zero repeat.
-Line 5162 
 uschar *code = *codeptr;
+Line 5837 
 uschar *code = *codeptr;
  uschar *last_branch = code;
  uschar *start_bracket = code;
  uschar *reverse_count = NULL;
+ open_capitem capitem;
+ int capnumber = 0;
  int firstbyte, reqbyte;
  int branchfirstbyte, branchreqbyte;
  int length;
  int orig_bracount;
  int max_bracount;
+ int old_external_options = cd->external_options;
  branch_chain bc;
  bc.outer = bcptr;
- bc.current = code;
+ bc.current_branch = code;
  firstbyte = reqbyte = REQ_UNSET;
-Line 5188 
 the code that abstracts option settings
+Line 5866 
 the code that abstracts option settings
  them global. It tests the value of length for (2 + 2*LINK_SIZE) in the
  pre-compile phase to find out whether anything has yet been compiled or not. */
+ /* If this is a capturing subpattern, add to the chain of open capturing items
+ so that we can detect them if (*ACCEPT) is encountered. This is also used to
+ detect groups that contain recursive back references to themselves. */
+ if (*code == OP_CBRA)
+   {
+   capnumber = GET2(code, 1 + LINK_SIZE);
+   capitem.number = capnumber;
+   capitem.next = cd->open_caps;
+   capitem.flag = FALSE;
+   cd->open_caps = &capitem;
+   }
  /* Offset is set zero to mark that this bracket is still open */
  PUT(code, 1, 0);
-Line 5232 
 for (;;)
+Line 5923 
 for (;;)
      return FALSE;
      }
+   /* If the external options have changed during this branch, it means that we
+   are at the top level, and a leading option setting has been encountered. We
+   need to re-set the original option values to take account of this so that,
+   during the pre-compile phase, we know to allow for a re-set at the start of
+   subsequent branches. */
+   if (old_external_options != cd->external_options)
+     oldims = cd->external_options & PCRE_IMS;
    /* Keep the highest bracket count in case (?| was used and some branch
    has fewer than the rest. */
-Line 5282 
 for (;;)
+Line 5982 
 for (;;)
      /* If lookbehind, check that this branch matches a fixed-length string, and
      put the length into the OP_REVERSE item. Temporarily mark the end of the
-     branch with OP_END. */
+     branch with OP_END. If the branch contains OP_RECURSE, the result is -3
+     because there may be forward references that we can't check here. Set a
+     flag to cause another lookbehind check at the end. Why not do it all at the
+     end? Because common, erroneous checks are picked up here and the offset of
+     the problem can be shown. */
      if (lookbehind)
        {
        int fixed_length;
        *code = OP_END;
-       fixed_length = find_fixedlength(last_branch, options);
+       fixed_length = find_fixedlength(last_branch, options, FALSE, cd);
        DPRINTF(("fixed length = %d\n", fixed_length));
-       if (fixed_length < 0)
+       if (fixed_length == -3)
+         {
+         cd->check_lookbehind = TRUE;
+         }
+       else if (fixed_length < 0)
          {
          *errorcodeptr = (fixed_length == -2)? ERR36 : ERR25;
          *ptrptr = ptr;
          return FALSE;
          }
-       PUT(reverse_count, 0, fixed_length);
+       else { PUT(reverse_count, 0, fixed_length); }
        }
      }
-Line 5309 
 for (;;)
+Line 6017 
 for (;;)
    compile a resetting op-code following, except at the very end of the pattern.
    Return leaving the pointer at the terminating char. */
-   if (*ptr != '|')
+   if (*ptr != CHAR_VERTICAL_LINE)
      {
      if (lengthptr == NULL)
        {
-Line 5330 
 for (;;)
+Line 6038 
 for (;;)
      PUT(code, 1, code - start_bracket);
      code += 1 + LINK_SIZE;
-     /* Resetting option if needed */
+     /* If it was a capturing subpattern, check to see if it contained any
+     recursive back references. If so, we must wrap it in atomic brackets.
+     In any event, remove the block from the chain. */
-     if ((options & PCRE_IMS) != oldims && *ptr == ')')
+     if (capnumber > 0)
+       {
+       if (cd->open_caps->flag)
+         {
+         memmove(start_bracket + 1 + LINK_SIZE, start_bracket,
+           code - start_bracket);
+         *start_bracket = OP_ONCE;
+         code += 1 + LINK_SIZE;
+         PUT(start_bracket, 1, code - start_bracket);
+         *code = OP_KET;
+         PUT(code, 1, code - start_bracket);
+         code += 1 + LINK_SIZE;
+         length += 2 + 2*LINK_SIZE;
+         }
+       cd->open_caps = cd->open_caps->next;
+       }
+     /* Reset options if needed. */
+     if ((options & PCRE_IMS) != oldims && *ptr == CHAR_RIGHT_PARENTHESIS)
        {
        *code++ = OP_OPT;
        *code++ = oldims;
-Line 5379 
 for (;;)
+Line 6108 
 for (;;)
      {
      *code = OP_ALT;
      PUT(code, 1, code - last_branch);
-     bc.current = last_branch = code;
+     bc.current_branch = last_branch = code;
      code += 1 + LINK_SIZE;
      }
-Line 5461 
 do {
+Line 6190 
 do {
       if (!is_anchored(scode, options, bracket_map, backref_map)) return FALSE;
       }
-    /* .* is not anchored unless DOTALL is set and it isn't in brackets that
+    /* .* is not anchored unless DOTALL is set (which generates OP_ALLANY) and
-    are or may be referenced. */
+    it isn't in brackets that are or may be referenced. */
     else if ((op == OP_TYPESTAR || op == OP_TYPEMINSTAR ||
-              op == OP_TYPEPOSSTAR) &&
+              op == OP_TYPEPOSSTAR))
-             (*options & PCRE_DOTALL) != 0)
       {
-      if (scode[1] != OP_ANY || (bracket_map & backref_map) != 0) return FALSE;
+      if (scode[1] != OP_ALLANY || (bracket_map & backref_map) != 0)
+        return FALSE;
       }
     /* Check for explicit anchoring */
-Line 5514 
 do {
+Line 6243 
 do {
       NULL, 0, FALSE);
     register int op = *scode;
+    /* If we are at the start of a conditional assertion group, *both* the
+    conditional assertion *and* what follows the condition must satisfy the test
+    for start of line. Other kinds of condition fail. Note that there may be an
+    auto-callout at the start of a condition. */
+    if (op == OP_COND)
+      {
+      scode += 1 + LINK_SIZE;
+      if (*scode == OP_CALLOUT) scode += _pcre_OP_lengths[OP_CALLOUT];
+      switch (*scode)
+        {
+        case OP_CREF:
+        case OP_NCREF:
+        case OP_RREF:
+        case OP_NRREF:
+        case OP_DEF:
+        return FALSE;
+        default:     /* Assertion */
+        if (!is_startline(scode, bracket_map, backref_map)) return FALSE;
+        do scode += GET(scode, 1); while (*scode == OP_ALT);
+        scode += 1 + LINK_SIZE;
+        break;
+        }
+      scode = first_significant_code(scode, NULL, 0, FALSE);
+      op = *scode;
+      }
     /* Non-capturing brackets */
     if (op == OP_BRA)
-Line 5532 
 do {
+Line 6289 
 do {
     /* Other brackets */
-    else if (op == OP_ASSERT || op == OP_ONCE || op == OP_COND)
+    else if (op == OP_ASSERT || op == OP_ONCE)
-      { if (!is_startline(scode, bracket_map, backref_map)) return FALSE; }
+      {
+      if (!is_startline(scode, bracket_map, backref_map)) return FALSE;
+      }
     /* .* means "start at start or after \n" if it isn't in brackets that
     may be referenced. */
-Line 5650 
 Returns:        pointer to compiled data
+Line 6409 
 Returns:        pointer to compiled data
                  with errorptr and erroroffset set
  */
- PCRE_EXP_DEFN pcre *
+ PCRE_EXP_DEFN pcre * PCRE_CALL_CONVENTION
  pcre_compile(const char *pattern, int options, const char **errorptr,
    int *erroroffset, const unsigned char *tables)
  {
-Line 5658 
 return pcre_compile2(pattern, options, N
+Line 6417 
 return pcre_compile2(pattern, options, N
  }
- PCRE_EXP_DEFN pcre *
+ PCRE_EXP_DEFN pcre * PCRE_CALL_CONVENTION
  pcre_compile2(const char *pattern, int options, int *errorcodeptr,
    const char **errorptr, int *erroroffset, const unsigned char *tables)
  {
-Line 5666 
 real_pcre *re;
+Line 6425 
 real_pcre *re;
  int length = 1;  /* For final END opcode */
  int firstbyte, reqbyte, newline;
  int errorcode = 0;
- #ifdef SUPPORT_UTF8
+ int skipatstart = 0;
- BOOL utf8;
+ BOOL utf8 = (options & PCRE_UTF8) != 0;
- #endif
  size_t size;
  uschar *code;
  const uschar *codestart;
-Line 5684 
 to fill in forward references to subpatt
+Line 6442 
 to fill in forward references to subpatt