patacongo opened a new pull request #1168: URL: https://github.com/apache/incubator-nuttx/pull/1168
## Summary In the FLAT build if CONFIG_LIB_SYSCALL=y, then the function task_spawn() will be duplicated.: One version in libs/libc/spawn and one version in sched/task. The version of task_spawn in lib/libc/spawn exists only if CONFIG_LIB_SYSCALL is selected. In that case, the one in sched/task/task_spawn.c should be static, at least in the FLAT build. The version of task_spawn.c in libs/libc/spawn simply marshals the parameters into a structure and calls nx_task_spawn(). If CONFIG_LIB_SYSCALL is defined then nx_task_spawn() will un-marshal the data can call the real task spawn. This nonsense is only necessary because task_spawn has 8 parameters and the maximum number of parameters in a system call is only 6. Without syscalls: Application should call directly in task_spawn() in sched/task/task_spawn.c and, hence, it must not be static With syscalls: Application should call the marshalling task_spawn() in libs/libc/spawn/lib_task_spawn.c -> That will call the autogenerated nx_task_spawn() proxy -> And generate a system call -> The system call will the unmarshalling nx_task_spawn() in sched/task/task_spawn.c -> Which will, finally, call the real task_spawn(). The side-effect of making task_spawn() static is that it then cannot be used within the OS. But as far as I can tell, nothing in the OS itself currently uses task_spawn() so I think it is safe to make it conditionally static. But that only protects from duplicate symbols in the useless case mentioned above. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
