Re: const from include/asm-i386/byteorder.h

[William Lee Irwin III <wli@holomorphy.com>]

On Mon, Jun 02, 2003 at 03:51:39PM +0400, Nikita Danilov wrote:
> Gcc info page:
> `const'
>      Many functions do not examine any values except their arguments,
>      and have no effects except the return value.  Basically this is
>      just slightly more strict class than the `pure' attribute above,
>      since function is not allowed to read global memory.
> So, it seems byte swapping functions should be __attribute__((const))
> Here is a patch:

I'm very skeptical, in particular, about these hunks:


On Mon, Jun 02, 2003 at 03:51:39PM +0400, Nikita Danilov wrote:
>  #include <linux/thread_info.h>
> -static inline struct task_struct *get_current(void) __attribute__ (( __const__ ));
> +static inline struct task_struct *get_current(void) __attribute_const;
>  static inline struct task_struct *get_current(void)
>  {
> ===== include/asm-arm/thread_info.h 1.6 vs edited =====
> --- 1.6/include/asm-arm/thread_info.h	Sat Dec 28 19:26:45 2002
> +++ edited/include/asm-arm/thread_info.h	Mon Jun  2 14:44:24 2003
> @@ -74,7 +74,7 @@
>  /*
>   * how to get the thread information struct from C
>   */
> -static inline struct thread_info *current_thread_info(void) __attribute__ (( __const__ ));
> +static inline struct thread_info *current_thread_info(void) __attribute_const;
>  
>  static inline struct thread_info *current_thread_info(void)
>  {

Someone needs to doublecheck whether this actually works. Last I heard,
it did not, but that could have changed since. It vaguely appears some
assumption about it working was made recently since __const__ was there.


-- wli