MDEV-28032 "git submodule update --depth 1" may fail with old Git

submodules.cmake: don't use "--depth 1" with old Git Old Git may not work with "--depth 1" when the referenced commit hash is far from HEAD. Newer Git improves the situation. For example: git/git@fb43e31 It's safe to not use "--depth 1" with old Git. Closes #2049

Author: kou

cmake/submodules.cmake

@@ -17,20 +17,29 @@ IF(GIT_EXECUTABLE AND EXISTS "${CMAKE_SOURCE_DIR}/.git")
  ${GIT_EXECUTABLE} config cmake.update-submodules yes")
  ELSEIF(git_config_get_result EQUAL 128)
  SET(update_result 0)
- ELSEIF (cmake_update_submodules MATCHES force)
- MESSAGE(STATUS "Updating submodules (forced)")
- EXECUTE_PROCESS(COMMAND "${GIT_EXECUTABLE}" submodule update --init --force --depth=1
- WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
- RESULT_VARIABLE update_result)
- ELSEIF (cmake_update_submodules MATCHES yes)
- EXECUTE_PROCESS(COMMAND "${GIT_EXECUTABLE}" submodule update --init --depth=1
- WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
- RESULT_VARIABLE update_result)
  ELSE()
- MESSAGE(STATUS "Updating submodules")
- EXECUTE_PROCESS(COMMAND "${GIT_EXECUTABLE}" submodule update --init --depth=1
- WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
- RESULT_VARIABLE update_result)
+ SET(UPDATE_SUBMODULES_COMMAND
+ "${GIT_EXECUTABLE}" submodule update --init --recursive)
+ # Old Git may not work with "--depth 1".
+ # See also: https://github.com/git/git/commit/fb43e31f2b43076e7a30c9cd00d0241cb8cf97eb
+ IF(NOT GIT_VERSION_STRING VERSION_LESS "2.8.0")
+ SET(UPDATE_SUBMODULES_COMMAND ${UPDATE_SUBMODULES_COMMAND} --depth 1)
+ ENDIF()
+ IF(cmake_update_submodules MATCHES force)
+ MESSAGE(STATUS "Updating submodules (forced)")
+ EXECUTE_PROCESS(COMMAND ${UPDATE_SUBMODULES_COMMAND} --force
+ WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
+ RESULT_VARIABLE update_result)
+ ELSEIF(cmake_update_submodules MATCHES yes)
+ EXECUTE_PROCESS(COMMAND ${UPDATE_SUBMODULES_COMMAND}
+ WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
+ RESULT_VARIABLE update_result)
+ ELSE()
+ MESSAGE(STATUS "Updating submodules")
+ EXECUTE_PROCESS(COMMAND ${UPDATE_SUBMODULES_COMMAND}
+ WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}"
+ RESULT_VARIABLE update_result)
+ ENDIF()
  ENDIF()
 ENDIF()