On Sat, Jul 08, 2017 at 10:21:06PM +0800, Shiyao Ma wrote:

Hi,

One thing I feel very un-comfortable when writing kernel module code
is the warning of `mixing declarations and code'.

Is `mixing declarations and code' still frowned upon by kernel
developers?

Yes.  It is a bad idea to ever do this in C code for a lot of various
reasons.

Or is it just a history burden that for some reason one can not mix
`declarations and code'?

Nope, please do not do it, your kernel code has to build with no
compiler warnings for it to be acceptable.

thanks,

greg k-h