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Showing content from https://en.cppreference.com/w/cpp/language/../types/numeric_limits/traps.html below:

std::numeric_limits<T>::traps - cppreference.com

static const bool traps;

(until C++11)

static constexpr bool traps;

(since C++11)

The value of std::numeric_limits<T>::traps is true for all arithmetic types T that have at least one value at the start of the program that, if used as an argument to an arithmetic operation, will generate a trap.

[edit] Standard specializations T value of std::numeric_limits<T>::traps /* non-specialized */ false bool false char usually true signed char usually true unsigned char usually true wchar_t usually true char8_t (since C++20) usually true char16_t (since C++11) usually true char32_t (since C++11) usually true short usually true unsigned short usually true int usually true unsigned int usually true long usually true unsigned long usually true long long (since C++11) usually true unsigned long long (since C++11) usually true float usually false double usually false long double usually false [edit] Notes

On most platforms integer division by zero always traps, and std::numeric_limits<T>::traps is true for all integer types that support the value ​0​. The exception is the type bool: even though division by false traps due to integral promotion from bool to int, it is the zero-valued int that traps. Zero is not a value of type bool.

On most platforms, floating-point exceptions may be turned on and off at run time (e.g. feenableexcept() on Linux or _controlfp on Windows), in which case the value of std::numeric_limits<T>::traps for floating-point types reflects the state of floating-point trapping facility at the time of program startup, which is false on most modern systems. An exception would be a DEC Alpha program, where it is true if compiled without -ieee.

[edit] Example

Possible output:

// GCC output:
bool:     traps = true
char:     traps = true
char16_t: traps = true
long:     traps = true
float:    traps = false
 
// Clang output:
bool:     traps = false
char:     traps = true
char16_t: traps = true
long:     traps = true
float:    traps = false
[edit] Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior LWG 497 C++98 it was unclear what is returned if trapping
is enabled or disabled at runtime returns the enable status
at the start of the program [edit] See also Floating-point environment identifies floating-point types that detect tinyness before rounding
(public static member constant) [edit] identifies the floating-point types that detect loss of precision as denormalization loss rather than inexact result
(public static member constant) [edit]

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