Satyam Sharma wrote: > On 5/20/07, Stefan Richter <[EMAIL PROTECTED]> wrote: >> > On 5/20/07, Stefan Richter <[EMAIL PROTECTED]> wrote: >> >> config A >> >> bool-or-tristate "option A" >> >> depends on !PLATFORM_X || HELPER_N_ON_PLATFORM_X [...] > Umm, if A requires helper code N (which is available only on platform X), [And, I assumed, 'A' works without helper 'N' on all platforms except 'X'. This is a synthetic example which might not have a real-world application.] > then why/how do we want A to depend on platforms _other_ than X?
The expression means: 'A' can be enabled on all platforms. Except on platform_X, there it can only be enabled if helper_N is built too. [...] >> depends on PM >> depends on SWAP >> depends on (X86 && !SMP) || >> (X86 && SUSPEND_SMP) || >> (PPC64_SWSUSP && !SMP) || >> (PPC64_SWSUSP && SUSPEND_SMP) || >> (FRV && !SMP) || >> (PPC32 && !SMP) > > Ok, so perhaps you actually meant X && N_ON_X above. No. I meant "(X && N_ON_X) || Any_one_platform_other_than_X" above. The 2nd example is a whitelist, while the 1st example is some kind of blacklist. A real-world example of blacklist style: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=a73df4dfdb0e01a1cbf119416a00e520a5e22306 (Lived only 2 days in Linus' tree.) -- Stefan Richter -=====-=-=== -=-= =-==- http://arcgraph.de/sr/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
