Language Reference

This document contains the complete description of the Intel® Fortran programming language, which includes Fortran 2003, Fortran 95, Fortran 90, and some Fortran 2008 language features. It contains 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/.

This manual is intended for experienced applications programmers who have a basic understanding of Fortran concepts and the Fortran 2003 and Standard Fortran language.

Some familiarity with your operating system is helpful. This manual is not a Fortran or programming tutorial.

This document contains the following sections:

New Language Features	Describes the major new features for this release.
Program Elements and Source Forms	Describes program elements, the Fortran standard character set, and source forms.
Data Types, Constants, and Variables	Describes intrinsic and derived data types, constants, variables (scalars and arrays), and substrings.
Expressions and Assignment Statements	Summarizes Fortran expressions and assignment statements, which are used to define or redefine variables.
Specification Statements	Summarizes specification statements, which are used to declare the attributes of data objects.
Dynamic Allocation	Summarizes statements used in dynamic allocation: ALLOCATE, DEALLOCATE, and NULLIFY. It also describes the effects of allocation and deallocation.
Execution Control	Summarizes constructs and statements that can transfer control within a program.
Program Units and Procedures	Describes program units (including modules), subroutines and functions, and procedure interfaces.
Intrinsic Procedures	Describes argument keywords used in intrinsic procedures and provides an overview of intrinsic procedures.
Data Transfer I/O Statements	Summarizes data transfer input/output (I/O) statements.
I/O Formatting	Describes the rules for I/O formatting.
File Operation I/O Statements	Summarizes auxiliary I/O statements you can use to perform file operations.
Compilation Control Statements	Summarizes compilation control statements INCLUDE and OPTIONS.
Directive Enhanced Compilation	Describes general directives and OpenMP* Fortran compiler directives.
Scope and Association	Describes scope, which refers to the area in which a name is recognized, and association, which is the language concept that allows different names to refer to the same entity in a particular region of a program.
Deleted and Obsolescent Language Features	Describes deleted features in Fortran 2003 and obsolescent language features in Fortran 2003.
Additional Language Features	Describes some statements and language features supported for programs written in older versions of Fortran.
Additional Character Sets	Describes the additional character sets available on Windows, Linux, and macOS* systems.
Data Representation Models	Describes data representation models for numeric intrinsic functions.
Run-Time Library Routines	Summarizes the many run-time library routines.
Summary of Language Extensions	Summarizes Intel Fortran extensions to the Fortran 2003 Standard.
A to Z Reference	Contains language summary tables and descriptions of all Intel® Fortran statements, intrinsics, directives, and module library routines, which are listed in alphabetical order.
Glossary	Contains abbreviated definitions of some commonly used terms in this manual.

Other books in this documentation set provide details about the features of the compilers, how to improve the run-time performance of Fortran programs, floating-point support, and compiler options.

For information on conventions used in this document, see Conventions.

For a summary of the latest Fortran 2003 features in this release, see Fortran 2003 Features.

For a summary of Fortran 2008 features in this release, see Fortran 2008 Features.