std::numeric_limits<T>::has_denorm_loss

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staticconstbool has_denorm_loss;		(until C++11)
staticconstexprbool has_denorm_loss;		(since C++11) (deprecated in C++23)

The value ofstd::numeric_limits<T>::has_denorm_loss istrue for all floating-point typesT that detect loss of precision when creating a subnormal number as denormalization loss rather than as inexact result (see below).

[edit]Standard specializations

`T`	value ofstd::numeric_limits<T>::has_denorm_loss
/* non-specialized */	false
bool	false
char	false
signedchar	false
unsignedchar	false
wchar_t	false
char8_t(since C++20)	false
char16_t(since C++11)	false
char32_t(since C++11)	false
short	false
unsignedshort	false
int	false
unsignedint	false
long	false
unsignedlong	false
longlong(since C++11)	false
unsignedlonglong(since C++11)	false
float	implementation-defined
double	implementation-defined
longdouble	implementation-defined

[edit]Notes

Standard-compliant IEEE 754 floating-point implementations of subnormal numbers are required to detect the loss of accuracy associated with the creation of such number, if it occurs, and may do so in one of the two distinct ways:

Denormalization loss: the delivered result differs from what would have been computed were exponent range unbounded.
Inexact result: the delivered result differs from what would have been computed were both exponent range and precision unbounded.

No implementation of denormalization loss mechanism exists (accuracy loss is detected after rounding, as inexact result), and this option was removed in the 2008 revision of IEEE Std 754.

libstdc++, libc++, libCstd, and stlport4 define this constant asfalse for all floating-point types. Microsoft Visual Studio defines it astrue for all floating-point types.

As with any floating-point computations, accuracy loss may raiseFE_INEXACT.

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

tinyness_before [static]	identifies floating-point types that detect tinyness before rounding (public static member constant)[edit]
has_denorm [static]	identifies the denormalization style used by the floating-point type (public static member constant)[edit]