CONFIG_PRINTK doesn't makes size smaller

["colin" <colin@realtek.com.tw>]

Hi there,
I tried to make kernel with CONFIG_PRINTK off. I considered it should become
smaller, but it didn't because it actually isn't an empty function, and
there are many copies of it in vmlinux, not just one. Here is its
definition:
    static inline int printk(const char *s, ...) { return 0; }

I change the definition to this and it can greatly reduce the size by about
5%:
    #define printk(...) do {} while (0)
However, this definition would lead to error in some situations. For
example:
    1. (printk)
    2. ret = printk

I hope someone could suggest a better definition of printk that can both
make printk smaller and eliminate errors.

Regards,
Colin