Re: [2.6 patch] loop.c: make two functions static

[Arjan van de Ven]

On Sun, 2005-01-23 at 18:32 +0800, andyliu wrote:
> hi, adrian
> 
> i always see patches which set functions and variables to static.
> what's the main difference between static and non-static things?

1) namespace; static functions/variables are not visible name wise to
other .c files
2) optimisation: because of 1), gcc can know that there are no outside
users (assuming also no address-off is taken, which gcc also knows), and
in that case gcc can do a series of extra optimisations (such as more
agressive inlining, since gcc knows the exact user count of the function
now, but also gcc 3.4 will do things like make the function be regparm=3
equivalent, tail/head optimisations are possible (eg partial inlining)



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