error: clobbers must be last on the x87 stack

Hi,

I've stumbled upon that error that makes no sense to me, being a complete novice in asm. The code is
  asm ("fsincos;" : "=t" (*ct), "=u" (*st) : "0" (t) : "st(7)");

Would there be a good soul to tell me how to correct it? I tried random permutations but to no avail.

Thanks,

Luc Bourhis

asm ("fsincos;" : "=t" (*ct), "=u" (*st) : "0" (t));

/jakob