Before this change, the SBOM generation only considered the CMAKE_INSTALL_PREFIX set at configure time for the purposes of file checksum computation, external document lookup, and SBOM file installation. When cmake --install . --prefix <path> is used, the install time CMAKE_INSTALL_PREFIX variable is overridden with the provided path, and can be different from the configure time value. This path was applied to the installation of regular files, libraries, etc, but not to the SBOM generation. This caused issues like not being able to find a library to compute its checksum. Instead of hard-coding the value to QT_STAGING_PREFIX, just don't pass a value at all, and rely on the new default of using an install-time-evaluated \${CMAKE_INSTALL_PREFIX}. Keep the ability of specifying a custom prefix just in case. Modify all the code that used a hard-coded CMAKE_INSTALL_PREFIX to use a install-time-evaluated one instead. As a drive-by, also set a proper default value for the INSTALL_SBOM_DIR option. Pick-to: 6.8 Fixes: QTBUG-131883 Change-Id: Ifde6ab282ac40f10c5bf51976121065c7dc631eb Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>