Compilation errors with gcc4.9 and c++1y

[madana gopal <madanagopal123@xxxxxxxxx>]

Hi,

I am compiling below code with c++1y flag with gcc 4.9.

#include <stdio.h>
register unsigned long sp asm ("sp");
int main()
{
    printf("[%d] \n",((unsigned long)(sp) >= 5));
    return 0;
}

I got the error as "Expected address of explicit register variable
sp". Here, the error is coming from the expression (sp). But it is not
coming when i use gcc4.9 without c++1y flag.
gcc4.9 is mandatory to be used in my project. Please let me know, what
is resolution for this ( any flags) or  the reason for this in c++1y.

Regards,
Madan