fix cpack windows

Author: dkropachev

CMakeLists.txt

@@ -259,7 +259,13 @@ set(CPACK_PACKAGE_VERSION ${PROJECT_VERSION_STRING})
 set(CPACK_PACKAGE_VERSION_MAJOR ${PROJECT_VERSION_MAJOR})
 set(CPACK_PACKAGE_VERSION_MINOR ${PROJECT_VERSION_MINOR})
 set(CPACK_PACKAGE_VERSION_PATCH ${PROJECT_VERSION_PATCH})
-set(CPACK_PACKAGING_INSTALL_PREFIX "${CMAKE_INSTALL_PREFIX}")
+if(WIN32)
+  # Prevent drive letters from bleeding into the staging path when CPack creates
+  # the temporary install tree on Windows.
+  set(CPACK_PACKAGING_INSTALL_PREFIX "/")
+else()
+  set(CPACK_PACKAGING_INSTALL_PREFIX "${CMAKE_INSTALL_PREFIX}")
+endif()
 set(CPACK_MONOLITHIC_INSTALL ON)
 set(CPACK_VERBATIM_VARIABLES ON)