java - JVM 上的浮点运算会在所有平台上给出相同的结果吗？

Question

我在多台机器上运行的应用程序中使用 Java，所有机器都需要获得相同的数学运算结果。使用 Java 的浮点原语是否安全？还是应该只使用定点数学库？

Answer 1

一般来说，不。但是，您可以使用 strictfp expressions :

Within an FP-strict expression, all intermediate values must be elements of the float value set or the double value set, implying that the results of all FP-strict expressions must be those predicted by IEEE 754 arithmetic on operands represented using single and double formats.

Within an expression that is not FP-strict, some leeway is granted for an implementation to use an extended exponent range to represent intermediate results; the net effect, roughly speaking, is that a calculation might produce "the correct answer" in situations where exclusive use of the float value set or double value set might result in overflow or underflow.