if(GIT_FOUND)
  execute_process(
    COMMAND "${GIT_EXECUTABLE}" describe --tags
    WORKING_DIRECTORY "${PROJECT_SOURCE_DIR}"
    RESULT_VARIABLE HAS_TERRA_VERSION
    OUTPUT_VARIABLE TERRA_VERSION
    ERROR_QUIET
  )
endif()

if(HAS_TERRA_VERSION EQUAL 0)
  string(STRIP "${TERRA_VERSION}" TERRA_VERSION)
  string(REGEX REPLACE "^(release-)" ""
    TERRA_VERSION "${TERRA_VERSION}"
  )
else()
  set(TERRA_VERSION unknown)
endif()

set(TERRA_VERSION_DEFINITIONS "TERRA_VERSION_STRING=\"${TERRA_VERSION}\"")