[RFC 4/6] ARC: Initial port to glibc

[Vineet Gupta]

On 06/27/2017 06:55 PM, Joseph Myers wrote:
> On Tue, 27 Jun 2017, Vineet Gupta wrote:
> 
>>>> +typedef struct sigcontext mcontext_t;
>>>
>>> You can avoid this problematic definition for a new architecture, even
>>> while we're still discussing eliminating it for existing architectures.
>>
>> So just use struct sigcontext as data type for uc_mcontext ?
> 
> No.  Define mcontext_t to be a struct without a tag, with the same layout
> as struct sigcontext, as the identifier sigcontext (and non-reserved
> identifiers for its elements) are not in the POSIX namespace permitted for
> ucontext.h.
> 
> https://sourceware.org/ml/libc-alpha/2017-06/msg00946.html

thx for this link - per comments there the contents of struct sigcontext could 
come from kernel which is

   struct sigcontext {
	struct user_regs_struct regs;
   };

Now I'd rather prefer to not duplicate user_regs_struct here, but instead just 
refer to kernel variant, something like ...

   typedef struct user_regs_struct mcontext_t;

Will that work or do I absolutely need to redefine this in userspace hdrs ?

-Vineet