imfs.h: warning cast from pointer to integer of different size

[Gedare Bloom]

On Thu, Mar 19, 2015 at 12:00 PM, Ric Claus <claus at slac.stanford.edu> wrote:
>
> On Mar 19, 2015, at 4:30 PM, Sebastian Huber <sebastian.huber at embedded-brains.de> wrote:
>
>>
>> ----- Joel Sherrill <joel.sherrill at oarcorp.com> schrieb:
>>>
>>>
>>> On March 19, 2015 9:52:56 AM CDT, Gedare Bloom <gedare at rtems.org> wrote:
>>>> On Thu, Mar 19, 2015 at 10:49 AM, Joel Sherrill
>>>> <joel.sherrill at oarcorp.com> wrote:
>>>>> Hi
>>>>>
>>>>> On one platform, we get a warning for this piece of code in imfs.h
>>>>>
>>>>> static inline ino_t IMFS_node_to_ino( const IMFS_jnode_t *node )
>>>>> {
>>>>>  return (ino_t) node;
>>>>> }
>>>>>
>>>>> On this target, "typedef unsigned long ino_t;" and
>>>>> sizeof(void *) < sizeof(unsigned long) so the cast is safe.
>>>>>
>>>>> Would we be better off with ino_t being uintptr_t since we
>>>>> do cast it back and forth?
>>>>>
>>>>> Any other suggestions?
>>>>>
>>>> The safest fix is to use the new CPU_Uint32ptr type. This resolves to
>>>> uintptr_t on most 32-bit+ archs.
>>>
>>> The type ino_t is defined in newlib so this doesn't work.
>>
>> The only requirement on the ino number is that it uniquely indentifies a node in a file system.  We only have a problem if sizeof(IMFS_jnode_t *) > sizeof(long).
>
Using the intermediate cast to uintptr_t is fine. We should keep ino_t
defined as a long.

> I’m curious what you all think about doing:
>
>   return (const char*)node - (const char*)0;
>
This still results in a pointer-type, the return value will be cast to
ino_t implicitly and give a similar warning.

>         Ric
>
> _______________________________________________
> devel mailing list
> devel at rtems.org
> http://lists.rtems.org/mailman/listinfo/devel