The CPACK_PACKAGE_VERSION handling is confusing me?

Code
1

I use CPACK for my project:

project(Boost-CMake LANGUAGES C CXX VERSION 1.81.0.3)

The resulting TGZ package is named: Boost-CMake-1.81.0-Darwin.tar.gz

I am missing my last RC number v1.81.0-rc3?

And if I use this project(CPMExampleBoost) the result is CPMExampleBoost-0.1.1-Darwin.tar.bz2
or CPMExampleBoost-1.84.0-Darwin.tar.gz …

How is this CPACK_PACKAGE_VERSION calculated, I see random values if the PROJECT_VERSION is not defined?

build/CPackConfig.cmake:set(CPACK_PACKAGE_VERSION "0.1.1")
2

AFAIK, CPack only models 3-component version numbers (e.g., the WiX generator’s backing tools only support 3 components and ranges on those values to boot due to registry representation limitations). You can craft the filename explicitly with CPACK_PACKAGE_FILE_NAME.