我在Mac 电脑上编译比特币源码，开发环境配置已经完成，
执行autogen.sh报错
localhost:bitcoin zsc$ ./autogen.sh
configure.ac:28: installing 'build-aux/install-sh'
configure.ac:28: installing 'build-aux/missing'
Makefile.am:8: error: Libtool library used but 'LIBTOOL' is undefined
Makefile.am:8: The usual way to define 'LIBTOOL' is to add 'LT_INIT'
Makefile.am:8: to 'configure.ac' and run 'aclocal' and 'autoconf' again.
Makefile.am:8: If 'LT_INIT' is in 'configure.ac', make sure
Makefile.am:8: its definition is in aclocal's search path.
Makefile.am: installing 'build-aux/depcomp'
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: error: am__fastdepCXX does not appear in AM_CONDITIONAL
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: The usual way to define 'am__fastdepCXX' is to add 'AC_PROG_CXX'
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: to 'configure.ac' and run 'aclocal' and 'autoconf' again
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: error: AMDEP does not appear in AM_CONDITIONAL
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: The usual way to define 'AMDEP' is to add one of the compiler tests
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: AC_PROG_CC, AC_PROG_CXX, AC_PROG_OBJC, AC_PROG_OBJCXX,
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: AM_PROG_AS, AM_PROG_GCJ, AM_PROG_UPC
/usr/local/Cellar/automake/1.16.1_1/share/automake-1.16/am/depend2.am: to 'configure.ac' and run 'aclocal' and 'autoconf' again
Makefile.am: error: C++ source seen but 'CXX' is undefined
Makefile.am: The usual way to define 'CXX' is to add 'AC_PROG_CXX'
Makefile.am: to 'configure.ac' and run 'autoconf' again.
parallel-tests: installing 'build-aux/test-driver'
autoreconf: automake failed with exit status: 1
根据这些信息，解决办法是要在configure.ac文件中加入AC_PROG_CXX
应该怎么加