Qt6 Cmake and Qmake build different behaviors

when I use configure -nomake examples -nomake tests -cmake, it fails at

– Performing Test CMAKE_HAVE_LIBC_PTHREAD - Success
– Found Threads: TRUE
– Using Qt bundled PCRE2.
– Found WrapPCRE2: TRUE
CMake Error at qtbase/cmake/QtSyncQtHelpers.cmake:7 (message):
Perl needs to be available to build Qt.
Call Stack (most recent call first):
qtbase/cmake/QtSyncQtHelpers.cmake:12 (qt_ensure_perl)
qtbase/cmake/QtModuleHelpers.cmake:168 (qt_ensure_sync_qt)
qtbase/src/corelib/CMakeLists.txt:29 (qt_internal_add_module)

– Configuring incomplete, errors occurred!
See also "D:/c/CMakeFiles/CMakeOutput.log".
See also "D:/c/CMakeFiles/CMakeError.log".
CMake Error at D:/qt6b/qtbase/cmake/QtProcessConfigureArgs.cmake:726 (message):
CMake exited with code 1.

but for qmake configure (without -cmake) everything works fine.

my windows dose not have perl installed and it works on Qt 5 build, which means perl is not needed, right?