${SUBJECT}, but let me explain it a little bit more. I am big autotools fan, and there are no problems with autotools options definition, everything is written in the configure.ac file through either AC_ARG_WITH or AC_ARG_ENABLE, but CMake projects usualli have few CMakeList.txt files ( in the subsirs), and I am confused what should I look for to find which build options CMake might have.
EDIT: or is is also possible to see ./configure --help after autoconf worked properly for autotools
cmake-gui (QT GUI) or ccmake (console UI) utilities are user-friendly ways to look up configurable options.