Re: RFC (branch prediction): PATCH to implement P0479R5, [[likely]] and [[unlikely]].

[Martin Liška]

Hi Jason.

Just small nits I noticed for:

cat test4.C
int a, b, c;

void
__attribute__((noinline))
bar()
{
  if (a == 123)
    [[likely]] c = 5;
  else
    [[likely]] b = 77;
}

int main()
{
  bar ();
  return 0;
}

$ g++ test4.C -c
test4.C: In function ‘void bar()’:
test4.C:8:16: warning: both branches of ‘if’ statement marked as ‘hot label’ 
[-Wattributes]
    8 |     [[likely]] c = 5;
      |                ^
    9 |   else
   10 |     [[likely]] b = 77;
      |                ~

1) I would expect 'likely' instead of 'hot label'
2) maybe we can put the carousel to the attribute instead of the first 
statement in the block?

Thanks,
Martin