The test-security-check and test-symbol-check scripts still reference Autoconf and it's behaviour:
def env_flags() -> list[str]:
# This should behave the same as AC_TRY_LINK, so arrange well-known flags
# in the same order as autoconf would.
#
# See the definitions for ac_link in autoconf's lib/autoconf/c.m4 file for
# reference.
The also expect CPPFLAGS to be passed into them, but this isn't happening from CMake: