Re: linux kernel building for mips malta target board

[David Daney <ddaney@avtrex.com>]

Stuart Anderson wrote:
> On Wed, 2 Nov 2005, David Daney wrote:
> 
>> Is this the problem you are seeing?:
>> In file included from include/linux/nfs_fs.h:15,
>>                 from init/do_mounts.c:12:
>> include/linux/pagemap.h: In function \x18fault_in_pages_readable\x19:
>> include/linux/pagemap.h:236: error: read-only variable \x18__gu_val\x19 
>> used as \x18asm\x19 output
>> include/linux/pagemap.h:236: error: read-only variable \x18__gu_val\x19 
>> used as \x18asm\x19 output
>> include/linux/pagemap.h:236: error: read-only variable \x18__gu_val\x19 
>> used as \x18asm\x19 output
>> include/linux/pagemap.h:236: error: read-only variable \x18__gu_val\x19 
>> used as \x18asm\x19 output
>>
>> The compiler behavior has changed since 4.0.1, but I think the new 
>> behavior is correct.  I am blaming the __get_user macro in 
>> include/asm-mips/uaccess.h. It should be possible to fix it there.  
>> The alternative is to hack up include/linux/pagemap.h.
> 
> 
> __get_user() is unhappy, with tpyes that are "const". It uses __typeof()
> to create a local variable that it wants to write to. I've intended to
> have offer up a patch by now, but, too manyunexpected thing have 
> happened in the firs thalf of this week.
> 

That is my analysis as well.  The typeof converts the const char * into 
a const char which is then unsuitable as the destination in an inline asm.

David Daney