bug#18777: [PATCH] dfa: improvement for checking of multibyte character boundary

[Paul Eggert]

Norihiro Tanaka wrote:
> However, first it is no longer portable after
> remove it.

"portable"?  This issue is independent of platform, surely.  By "portable" did 
you mean "robust in the presence of future changes?

> Second if it is compiled with GCC 4.3 or later, the function
> is inlined by and "WCP == NULL &&" will be pruned.

True, but I wasn't worried so much about that.  I was worried about the case 
where WCP != NULL: there, the inlined function will be slower because it won't 
use the faster approach of checking always_character_boundary[*p]: it'll always 
use the much-slower loop.