That is because with x87 floating point, when the number is in registers, it is ...

		yuhong on Jan 4, 2011 \| parent \| context \| favorite \| on: PHP 5.3.3 hangs on numeric value 2.225073858507201... That is because with x87 floating point, when the number is in registers, it is 80-bit, but when the compiler spills it to memory, it is 64-bit, which is why -ffloat-store works.