From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Sat, 12 Sep 2009 15:53:03 +0100 Subject: [PATCH v2 RESEND 1/2] ARM: Introduce ARM_L1_CACHE_SHIFT to define cache line size In-Reply-To: References: <1252771155-5828-1-git-send-email-kirill@shutemov.name> <4AABA3F7.2050301@ru.mvista.com> <4AABAE4D.6050909@ru.mvista.com> Message-ID: <20090912145303.GA15899@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, Sep 12, 2009 at 05:38:31PM +0300, Kirill A. Shutemov wrote: > On Sat, Sep 12, 2009 at 5:21 PM, Sergei Shtylyov > wrote: > > Hello. > > > > Kirill A. Shutemov wrote: > >> You can write anything in your .config (like 2+3), so I think parens is > >> needed. > >> > > > > ?You can -- but that won't be an integer option. > > But kernel will be still compilable, but broken. > > I think parens for defines from .config is a good practice. However, defines are not taken from .config. The .config file is processed by the kernel configurator, which writes out the autoconf.h header. It does this by re-evaluating the contents of .config against all the Kconfig files. It does not merely copy .config to autoconf.h. In fact, if you try to write '2+3' into your .config, Kconfig will reject it. Eg: .config:210:warning: symbol value '127+1' invalid for OMAP_32K_TIMER_HZ and then it asks you to provide a valid value instead. So yes, as pointed out, the parens are not required since Kconfig will ensure that the symbol is a simple integer.