[PATCH] Fix PR23471

[Hurugalawadi, Naveen]

>> With -O1 there is -fno-strict-overflow in effect which is not
>> TYPE_OVERFLOW_UNDEFINED.

Thanks for the details. The below code has the following condition
and hence not working for O1. 
if (FLOAT_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))

Then PR23471 is fixed with the current sources.

Thanks,
Naveen