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

ID 767251
Date 3/31/2023
Public

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Document Table of Contents

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

This document is for version 2021.9 of Intel® Fortran Compiler Classic (ifort) and version 2023.1 of Intel® Fortran Compiler (ifx).

This guide provides information about Intel® Fortran Compiler Classic (ifort) and its runtime environment, and about Intel® Fortran Compiler (ifx), which is a new compiler based on the Intel Fortran Compiler Classic (ifort) frontend and runtime libraries, using LLVM backend technology.

Refer to the Intel® Fortran Compiler product page and the Release Notes for more information about features, specifications, and downloads.

Use this guide to learn about:

  • Compiler Setup: How to invoke the compiler on the command line or from within an IDE.
  • Compiler Options: Information about options you can use to affect optimization, code generation, and more.
  • Language Reference: Information on language syntax and semantics, on adherence to various Fortran standards, and on extensions to those standards.
  • OpenMP* Support: Details about compiler support for OpenMP 5.0 Version TR4 features and some OpenMP Version 5.1 features.
  • Fortran Language Extensions: Information on using additional implementation features, including creating a Component Object Model server, generating listing and map files, and more.
  • Mixed-Language Programming: Information about Fortran and C interoperable procedures and data types, as well as various specifics of mixed-language programming.
  • Runtime Error Messages: Information about the errors processed by the Intel® Fortran runtime library (RTL).

For more information, refer to Introducing the Intel® Fortran Compiler Classic and Intel® Fortran Compiler.

Notices and Important Information

  • Support for 32-bit targets is deprecated in ifort and may be removed in a future release. ifx does not support 32-bit targets.
  • macOS* support is deprecated for Intel® Fortran Compiler Classic (ifort) in the oneAPI 2023.1 release. macOS support for Intel® Fortran Compiler Classic (ifort) will not be available starting with the oneAPI 2024.0 release:
    • Support for Interprocedural Optimization (IPO) is disabled for macOS SDK 11 or higher.
    • Xcode* integration capabilities within our Intel® Fortran Compiler bundle have been removed. The command-line interface remains fully functional for macOS.

      Installing 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

Using the Compiler Documentation

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