x86: Forces precision of floating-point expressions.
This option causes the compiler to convert the value of a floating-point expression or function to the type on the left side of an assignment rather than leave the value in a register when the following is true:
The expression or function is assigned to a variable.
The expression is cast to a shorter floating-point type.
To turn off this option, use the -nofstore option.
Due to roundoffs and truncation, the results can be different from those that are generated from the register values.
-nofstore