Does casting double to float always return same value?

Question

Does casting double to float always produce same result, or can there be some \"rounding differences\"?

For example, is x in

Answer 1

The results should not be language dependent, unless the language deviates from the IEEE specification.

All floats can be exactly represented as doubles, so the round trip from float to double to float should yield the same value that you started with.

Similarly, casting any double value to float should always yield the same result, but, of course, there are many different double values that would truncate to the same float value.