Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference

ID 767251
Date 7/13/2023
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

IEEE_SUPPORT_SUBNORMAL

Inquiry Module Intrinsic Function (Generic): Returns whether the processor supports IEEE subnormal numbers.

Module

USE, INTRINSIC :: IEEE_ARITHMETIC

result = IEEE_SUPPORT_SUBNORMAL ([x])

x

(Input; optional) Must be of type REAL; it can be scalar or array valued.

Results

The result is a scalar of type default logical. If x is omitted, the result has the value true if the processor supports arithmetic operations and assignments with subnormal numbers for all real values; otherwise, false.

If x is specified, the result has the value true if the processor supports arithmetic operations and assignments with subnormal numbers for real variables of the same kind type parameter as x; otherwise, false.

IEEE_SUPPORT_SUBNORMAL () and IEEE_SUPPORT_SUBNORMAL (0.0_16) return .TRUE. even though Intel® Fortran’s implementation does not signal when an underflow results in a REAL (16) subnormal value. Intel® Fortran’s implementation does signal when an underflow results in a REAL (16) zero.

Example

IEEE_SUPPORT_SUBNORMAL () has the value true if IEEE subnormal numbers are supported for all real types.