On 25/11/15 05:06 AM, Clemens Ladisch wrote:
> Mathias Krause wrote:
>> [...]
>> So, prior extending the usage of the __read_only annotation some
>> toolchain support is needed. Maybe a gcc plugin that'll warn/error on
>> code that writes to such a variable but is not __init itself.
> 
> Or mark them as "const".  This would require the initialization code to
> cast it away, probably with a helper macro.
> 
> 
> Regards,
> Clemens
> 

That would be undefined. It would only be safe if you exposed a const
pointer as the only way of accessing a non-const variable. It would be
silly to mangle the code simply to get a warning as it should be easy
enough to add to GCC. The usefulness isn't just limited to the kernel
either.