Intel® Fortran Compiler Developer Guide and Reference

This document is for version 2025.2 of the Intel® Fortran Compiler (ifx).

Attention

The Intel® Fortran Compiler Classic (ifort) was discontinued after the 2024.2 version release. To access past versions of documentation that includes content for the Intel® Fortran Compiler Classic (ifort):

Intel recommends transitioning to the LLVM-based Intel® Fortran Compiler (ifx) for continued Linux* and Windows* support, new language support, new language features, and optimizations. For the latest information on transitioning from ifort to ifx, see the Porting Guide for ifort Users to ifx.

This developer guide provides information about the Intel® Fortran Compiler (ifx), which uses 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:

For more information, refer to the Intel® Fortran Compiler Introduction.

Notices and Important Information

In this document, you may see features labeled as experimental. An experimental feature is one that requires further testing and possible refinement. Depending on testing results, such features may be fully defined and implemented or they may be removed in a future release.

Using the Compiler Documentation

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 provided instructions.

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.