Conformance, Compatibility, and Fortran Features

This section contains information about Fortran language standards conformance, language compatibility, and supported features.

Language Standards Conformance

The Fortran standard has undergone several revisions since its initial publication as FORTRAN 66 (also known as FORTRAN IV). Subsequent revisions have been FORTRAN 77, Fortran 90, Fortran 95, Fortran 2003, Fortran 2008, Fortran 2018, and Fortran 2023. Each revision has added new features; some revisions have labeled features as "deprecated" (or obsolescent) or they have removed them. Intel® Fortran continues to support deprecated and deleted features.

Intel® Fortran conforms to these standards:

The Fortran Standards committee is currently answering questions of interpretation on Fortran 2018 language features. Any answers given by the committee that are related to features implemented in Intel® Fortran may result in changes in future releases of the Intel® Fortran Compiler, even if the changes produce incompatibilities with earlier releases of Intel® Fortran.

Intel Fortran provides a number of extensions to the Fortran 2018 Standard. In the language reference, extensions (non-standard features) are displayed in this color.

Intel® Fortran also includes support for programs that conform to the previous Fortran standards (ANSI X3.9-1978 and ANSI X3.0-1966), the International Standards Organization standard ISO 1539-1980 (E), the Federal Information Processing Institute standard FIPS 69-1, and the Military Standard 1753 Language Specification.

Language Compatibility

Intel® Fortran is highly source-compatible with Compaq* Visual Fortran on supported systems, and it is substantially source-compatible with DEC* Fortran 90 and VAX* FORTRAN 77.

Fortran 2023 Features

The following Fortran 2023 features are new in this release:

The following Fortran 2023 features are also supported:

Fortran 2018 Features

Fortran 2018 is fully supported, including the following features:

Fortran 2008 Features

Fortran 2008 is fully supported, including the following features:

Fortran 2003 Features

Fortran 2003 is fully supported, including the following features:

See Also