Just as another data point, I tried this version under cygwin and it also fails to give an equality.

\n\tfldl LC0\n\tsubl $8,%esp\n\tfstpl (%esp)\n\tfldl LC1\n\tsubl $8,%esp\n\tfstpl (%esp)\n\tcall _pow\n\taddl $16,%esp\n\tfldl LC2\n\tfdivp %st,%st(1)\n\tfstpl -8(%ebp)\n\tfldl LC0\n\tsubl $8,%esp\n\tfstpl (%esp)\n\tfldl LC1\n\tsubl $8,%esp\n\tfstpl (%esp)\n\tcall _pow\n\taddl $16,%esp\n\tfldl LC2\n\tfdivp %st,%st(1)\n\tfldl -8(%ebp)\n\tfucompp\n\tfnstsw %ax\n\tandb $68,%ah\n\txorb $64,%ah\n\tjne L3\n