On 12.4.2012 03:19, Linus Torvalds wrote: > On Wed, Apr 11, 2012 at 4:58 PM, Linus Torvalds > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: >> >> I think we can easily drop IS_ENABLED() if it has been causing >> problems. And it clearly is. What is really causing problems is that kconfig has no view of the entire kernel configuration. >> And I had never even looked at that generated file. It's disgusting. >> We need to stop doing that. It must be driving compile-times up too - >> just parsing that monster is RealWork(tm). You forgot that it also contributes to global warming. > Oh, but I have a sick and twisted mind. And I'm incredibly smart and > photogenic too. > > Here's an implementation of IS_ENABLED() that works in C. Well, > "gcc-C". It depends on the optimizer DTRT, but gcc really does seem to > do it. > > Ready? You *will* go blind - blinded by the pure beauty and intellect > in this thing: > > #define IS_DEFINED(x) (__stringify(CONFIG_##x)[0]=='1') Nice. Maybe we could make it simply #define IS_DEFINED(x) (__stringify(x)[0]=='1') so that the users are easily grepable and it is obvious that a config option is being tested, like in the current implementation. The only thing we lose is the check if 'x' is really a boolean or tristate option. But it turns out that even now this does not work in all cases. Michal -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
