ENABLE_PYTHON3 is used in the CMakeLists.txt in the bindings
directory but if it's defined alone it won't trigger building the
bindings.
ADD_SUBDIRECTORY (src)
ADD_SUBDIRECTORY (ext)
ADD_SUBDIRECTORY (tools)
-IF (ENABLE_PERL OR ENABLE_PYTHON OR ENABLE_RUBY OR ENABLE_TCL)
+IF (ENABLE_PERL OR ENABLE_PYTHON OR ENABLE_PYTHON3 OR ENABLE_RUBY OR ENABLE_TCL)
ADD_SUBDIRECTORY (bindings)
-ENDIF (ENABLE_PERL OR ENABLE_PYTHON OR ENABLE_RUBY OR ENABLE_TCL)
+ENDIF (ENABLE_PERL OR ENABLE_PYTHON OR ENABLE_PYTHON3 OR ENABLE_RUBY OR ENABLE_TCL)
ADD_SUBDIRECTORY (examples)
ADD_SUBDIRECTORY (doc)