Intel® Fortran Compiler Classic and Intel® Fortran Compiler (Beta) Developer Guide and Reference

This document is for version 2021.2 of the compilers.

This document contains information about Intel® Fortran Compiler Classic (ifort) and its runtime environment, and about Intel® Fortran Compiler (Beta) (ifx), which is a new compiler based on the Intel Fortran Compiler Classic (ifort) frontend and runtime libraries, using LLVM backend technology. For more information, see Introducing the Intel® Fortran Compiler Classic and Intel® Fortran Compiler (Beta).

Note

Support for 32-bit targets is deprecated in ifort and may be removed in a future release. ifx does not support 32-bit targets.

Note

macOS* is supported for the ifort compiler. However, support for Interprocedural Optimization (IPO) is disabled for macOS* SDK 11 or higher.

Note

Xcode* integration capabilities within our Intel® Fortran Compiler bundle have been removed. The command-line interface remains fully functional for macOS*.

Keep in mind that installation of Xcode is still recommended because command-line tools from Xcode are required by the command-line compiler. However, you can install just the Xcode Command Line Tools with this command from a terminal window:

xcode-select --install

The following are some important features of the compiler:

Compiler Setup

Compiler Setup explains how to invoke the compiler on the command line or from within an IDE.

Compiler Options

Compiler Options provides information about options you can use to affect optimization, code generation, and more. This document provides an Alphabetical List of Compiler Options for your reference.

Language Reference

The Language Reference provides information on language syntax and semantics, on adherence to various Fortran standards, and on extensions to those standards.

For information about the Fortran standards, visit the Fortran standards technical committee website at http://j3-fortran.org/.

Fortran Language Extensions

Fortran Language Extensions provides information about how to use additional implementation features, such as creating a Component Object Model server and generating listing and map files, among others.

Mixed Language Programming

Mixed Language Programming provides information about Fortran and C interoperable procedures and data types, as well as various specifics of mixed-language programming.

List of Run-Time Error Messages

List of Run-Time Error Messages describes the errors processed by the Intel® Fortran run-time library (RTL).

Context Sensitive/F1 Help

To use the Context Sensitive/F1 Help feature, visit the Download Documentation: Intel® Compiler (Current and Previous) page and follow the instructions provided there.

Download Previous Versions of the Developer Guide and Reference

Visit the Download Documentation: Intel® Compiler (Current and Previous) page to download PDF or FAR HTML versions of previous compiler documentation.

Note

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If you use Mozilla Firefox*, you may encounter an issue where the Search tab does not work. As a workaround, you can use the Contents and Index tabs or a third-party search tool to find your content.