pcre2_set_compile_extra_options - Man Page

#include <pcre2.h>

int pcre2_set_compile_extra_options(pcre2_compile_context *ccontext,
  uint32_t extra_options);

This function sets additional option bits for pcre2_compile() that are housed in a compile context. It completely replaces all the bits. The extra options are:

 PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK     Allow \K in lookarounds
 PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES  Allow \x{d800} to \x{dfff}
                                        in UTF-8 and UTF-32 modes
 PCRE2_EXTRA_ALT_BSUX                 Extended alternate \u, \U, and
                                        \x handling
 PCRE2_EXTRA_ASCII_BSD                \d remains ASCII in UCP mode
 PCRE2_EXTRA_ASCII_BSS                \s remains ASCII in UCP mode
 PCRE2_EXTRA_ASCII_BSW                \w remains ASCII in UCP mode
 PCRE2_EXTRA_ASCII_DIGIT              [:digit:] and [:xdigit:] POSIX classes
                                        remain ASCII in UCP mode
 PCRE2_EXTRA_ASCII_POSIX              POSIX classes remain ASCII in
                                        UCP mode
 PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL    Treat all invalid escapes as
                                        a literal following character
 PCRE2_EXTRA_CASELESS_RESTRICT        Disable mixed ASCII/non-ASCII
                                        case folding
 PCRE2_EXTRA_ESCAPED_CR_IS_LF         Interpret \r as \n
 PCRE2_EXTRA_MATCH_LINE               Pattern matches whole lines
 PCRE2_EXTRA_MATCH_WORD               Pattern matches "words"

There is a complete description of the PCRE2 native API in the pcre2api page and a description of the POSIX API in the pcre2posix page.