This just got me. I upgraded macOS to Mojave (w/ latest Xcode) and I always build w/ maintainer-mode. The problem is that libxml2 will include various unicode/*.h files that have C++ type comments, which causes building to fail (due to Werror). Work around this.
@@ -114,6 +114,10 @@ AC_DEFUN([FIND_LIBXML2], [
if test -n "${xml2_path}" ; then
ac_cv_libxml2=yes
XML2_INCLUDES="${xml2_path}"
+ dnl libxml2 includes unicode/*.h files which uses C++ comments
+ if test "$GCC" = "yes"; then
+ APACHE_ADD_GCC_CFLAG([-Wno-error=comment])
+ fi
else
ac_cv_libxml2=no
fi
