FLT_EVAL_METHOD

 

C++

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is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)
is_move_constructibleis_trivially_move_constructibleis_nothrow_move_constructible (C++11)(C++11)(C++11)
is_assignableis_trivially_assignableis_nothrow_assignable (C++11)(C++11)(C++11)
is_copy_assignableis_trivially_copy_assignableis_nothrow_copy_assignable (C++11)(C++11)(C++11)
is_move_assignableis_trivially_move_assignableis_nothrow_move_assignable (C++11)(C++11)(C++11)
is_destructibleis_trivially_destructibleis_nothrow_destructible (C++11)(C++11)(C++11)
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Type transformations
aligned_storage (C++11) aligned_union (C++11) decay (C++11) enable_if (C++11) void_t (C++17)	conditional (C++11) common_type (C++11) underlying_type (C++11) result_of (C++11)

 

C numeric limits interface

FLT_ROUNDS

FLT_EVAL_METHOD

 

Defined in header <cfloat>
#define FLT_EVAL_METHOD /* implementation defined */		(since C++11)

Specifies the precision in which all floating-point arithmetic operations other than assignment and cast are done.

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.

See also

C documentation for FLT_EVAL_METHOD