Hi,

this patch wraps ASM_OUTPUT_LABELREF in a "do {} while (0)".

Without, we can run into a dangling else, generating this kind of warning:
...
$ cat test.c
void bar (int);

int c;

#define barc					\
   if (c)					\
     bar (1);					\
   else						\
     bar (2)

void
foo (int d)
{
   if (d)
     barc;
}
$ gcc test.c -S -Wall
test.c: In function ‘foo’:
test.c:14:6: warning: suggest explicit braces to avoid ambiguous ‘else’ 
[-Wparentheses]
    if (d)
       ^
...

Build for mips target.

Committed as obvious.

Thanks,
- Tom