Install CMake package version file

Reviewed-on: #19

CMakeLists.txt

@@ -361,8 +361,17 @@ configure_package_config_file(
     INSTALL_DESTINATION ${akerror_install_cmakedir}
 )
 
+# The SOVERSION is the project major version, so packages with the same major
+# are ABI-compatible and a different major must be rejected.
+write_basic_package_version_file(
+    "${CMAKE_CURRENT_BINARY_DIR}/akerrorConfigVersion.cmake"
+    VERSION ${PROJECT_VERSION}
+    COMPATIBILITY SameMajorVersion
+)
+
 install(FILES
     "${CMAKE_CURRENT_BINARY_DIR}/akerrorConfig.cmake"
+    "${CMAKE_CURRENT_BINARY_DIR}/akerrorConfigVersion.cmake"
     DESTINATION ${akerror_install_cmakedir}
 )