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A floating result overflows if the magnitude of the mathematical result is finite but so large that the mathematical result cannot be represented without extraordinary roundoff error in an object of the specified type. If a floating result overflows and default rounding is in effect, then the function returns the value of the macro
HUGE_VAL,HUGE_VALF, orHUGE_VALLaccording to the return type, with the same sign as the correct value of the function; if the integer expressionmath_errhandling & MATH_ERRNOis nonzero, the integer expressionerrnoacquires the valueERANGE; if the integer expressionmath_errhandling & MATH_ERREXCEPTis nonzero, the ‘‘overflow’’ "overflow" floating-point exception is raised.
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