src/sys/sendfile/CMakeLists.txt - llvm-project/libc - Git at Google

 if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
 endif()

 add_entrypoint_object(
   sendfile
   ALIAS
   DEPENDS
     .${LIBC_TARGET_OS}.sendfile
 )
	if(EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
	add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/${LIBC_TARGET_OS})
	endif()

	add_entrypoint_object(
	sendfile
	ALIAS
	DEPENDS
	.${LIBC_TARGET_OS}.sendfile
	)