自己编写一个 PHP 扩展，可以正常编译，使用的时候报错 Unable to load dynamic library ... _pcre_free

自己编写了一个扩展，引用了一个第三方的 c++ 的库，编译的时候一切正常，加载到 PHP 后运行报错

PHP Warning:  PHP Startup: Unable to load dynamic library '/Users/hooklife/Projects/php-build/7.3/lib/php/extensions/no-debug-non-zts-20180731/r3_route.so' (tried: /Users/hooklife/Projects/php-build/7.3/lib/php/extensions/no-debug-non-zts-20180731/r3_route.so (dlopen(/Users/hooklife/Projects/php-build/7.3/lib/php/extensions/no-debug-non-zts-20180731/r3_route.so, 9): Symbol not found: _pcre_free
  Referenced from: /Users/hooklife/Projects/php-build/7.3/lib/php/extensions/no-debug-non-zts-20180731/r3_route.so
  Expected in: flat namespace

这是我的 config.m4

AC_PROG_CC
AC_PROG_CC_STDC
AC_FUNC_VPRINTF
AC_CHECK_FUNCS([gettimeofday memset strchr strdup strndup strstr pcre])

PHP_ARG_ENABLE(r3_route, whether to enable r3_route support,
[  --enable-r3_route          Enable r3_route support], no)


if test "$PHP_R3_ROUTE" != "no"; then

  r3_sources="
  r3/src/str.c
  r3/src/token.c
  r3/src/slug.c
  r3/src/edge.c
  r3/src/node.c
  r3/src/list.c
  r3/src/match_entry.c"

  AC_DEFINE(HAVE_PCRE, 1, [ ])
  PHP_ADD_INCLUDE(/usr/local/include/pcre)
  PHP_ADD_LIBRARY_WITH_PATH(z,/usr/local/lib/pcre, R3_ROUTE_SHARED_LIBADD)
  PHP_ADD_INCLUDE("$srcdir/r3/include")


  PHP_NEW_EXTENSION(r3_route, $r3_sources r3_route.c, $ext_shared)

  PHP_SUBST(R3_ROUTE_SHARED_LIBADD)
fi

查找了很长时间没找到相关内容，请求大家帮帮忙。随便问下有没有什么专门的 PHP 扩展的群或者论坛，我能更方便的获取信息

感谢～～