FE_DIVBYZERO, FE_INEXACT, FE_INVALID, FE_OVERFLOW, FE_UNDERFLOW, FE_ALL_EXCEPT
From cppreference.com
Defined in header <<fenv.h>>


#define FE_DIVBYZERO /*implementation defined power of 2*/ 
(since C99)  
#define FE_INEXACT /*implementation defined power of 2*/ 
(since C99)  
#define FE_INVALID /*implementation defined power of 2*/ 
(since C99)  
#define FE_OVERFLOW /*implementation defined power of 2*/ 
(since C99)  
#define FE_UNDERFLOW /*implementation defined power of 2*/ 
(since C99)  
#define FE_ALL_EXCEPT FE_DIVBYZERO  FE_INEXACT  \ FE_INVALID  FE_OVERFLOW  \ 
(since C99)  
All these macro constants (except FE_ALL_EXCEPT) expand to integer constant expressions that are distinct powers of 2, which uniquely identify all supported floatingpoint exceptions. Each macro is only defined if it is supported.
The macro constant FE_ALL_EXCEPT, which expands to the bitwise OR of all other FE_*
, is always defined and is zero if floatingpoint exceptions are not supported by the implementation.
Constant  Explanation 
FE_DIVBYZERO

division by zero occurred during the earlier floatingpoint operation 
FE_INEXACT

inexact result: rounding was necessary to store the result of the earlier floatingpoint operation 
FE_INVALID

invalid operation: the earlier floatingpoint operation could not performed 
FE_OVERFLOW

the result of the earlier floatingpoint operation was too large to be representable 
FE_UNDERFLOW

the result of the earlier floatingpoint operation was subnormal 
FE_ALL_EXCEPT

bitwise OR of all supported floatingpoint exceptions 
The implementation may define additional macro constants in <fenv.h>
to identify additional floatingpoint exceptions. All such constants begin with FE_
followed by at least one uppercase letter.
Example
This section is incomplete Reason: no example 
See also
C++ documentation for floating point exception macros
