# FLT_EVAL_METHOD

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Type support
 size_t ptrdiff_t NULL max_align_t(since C11) offsetof Numeric limits

Numeric limits
 FLT_ROUNDS FLT_EVAL_METHOD(C99)

 Defined in header  #define FLT_EVAL_METHOD /* implementation defined */ (since C99)

Specifies range and precision of floating-point values obtained from floating-point constants and from all operations (operators, implicit conversions of operands) except assignment, cast, and library function call.

 Value Explanation negative values except -1 implementation-defined behavior -1 the default precision is not known 0 all operations and constants evaluate in the range and precision of the type used. Additionally, float_t and double_t are equivalent to float and double respectively 1 all operations and constants evaluate in the range and precision of double. Additionally, both float_t and double_t are equivalent to double 2 all operations and constants evaluate in the range and precision of long double. Additionally, both float_t and double_t are equivalent to long double

### Notes

Regardless of the value of FLT_EVAL_METHOD, any floating-point expression may be contracted, that is, calculated as if all intermediate results have infinite range and precision (unless #pragma STDC FP_CONTRACT is off)

Cast and assignment strip away any extraneous range and precision: this models the action of storing a value from an extended-precision FPU register into a standard-sized memory location.