Intel® Fortran Compiler 19.0 for Linux* Release Notes for Intel® Parallel Studio XE 2019

ID 658750
Updated 8/4/2021
Version Latest



This document provides a summary of new and changed product features and includes notes about features and problems not described in the product documentation. 

Please see the licenses included in the distribution as well as the Disclaimer and Legal Information section of these release notes for details. Please see the following links for information on this release of the Intel® Fortran Compiler 19.0.

Change History

This section highlights important changes from the previous product version and changes in product updates.

Changes in Update 7 (Intel® Fortran Compiler 19.0.9)

This is release for Intel® Compilers 2019 Update 7, compilers version 19.0.9.  Highlights for this release:

  • 2019 Update 7 is provided for Linux only.
  • 2019 Update 7 is only released in Composer Edition.  No Profession or Cluster Edition packages are provided for this update.
  • 2019 Update 7 is only a Compiler update.  No other components have changed since PSXE 2019 Update 6.
  • Only the Intel® C++ Compiler has changed.  It has a fix for a minor issue related to the _mm_prefetch intrinsic.  If you do not use the _mm_prefetch you will get no benefit from this update.
  • 2019 Update 7 has no fixes for the Fortran Compiler.
  • Both C++ and Fortran Compilers have updated license checking library files to address potential security issues.

The compiler version appears in the version string as version 19.0.9 in this PSXE 2019 Update 7.  This is due to compiler updates released outside of Parallel Studio packages that used compiler versions 19.0.7 and 19.0.8.  For details on compiler versions included in Parallel Studio releases please visit Intel Ccompiler and Composer Update Version Numbers to Compiler Version Number Mapping.

Changes in Update 6 (Intel® Fortran Compiler 19.0.8)

This is release for Intel® Compilers 2019 Update 6, compilers version 19.0.8.  Highlights for this release:

  • Intel® Parallel Studio XE 2019 Update 6 Composer Edition contains Compiler Update 8.
  • Compilers Update 6 and 7 are not available to the general public.
  • Compilers Update 6 and 7 were special releases not available to all customers.
  • Corrections to reported problems.
  • Includes certain functional and security updates. We recommend updating for these functional and security updates.

Changes in Update 5 (Intel® Fortran Compiler 19.0.5)

Highlights for this update release:

  • Red Hat Enterprise Linux* 8 support
  • Includes certain functional and security updates.  We recommend updating for these functional and security updates.
  • Floating License Server Upgrade required
  • Corrections to reported problems

Changes in Update 4 Eng/Jpn (Intel® Fortran Compiler 19.0.4 build 243)
IRC post date 05/23/2019

This is the final release of 2019 Update 4.  Use this compiler unless you need to validate against the same compiler used to publish SPEC benchmark (see Update 4 SPEC227 below).

Changes in Update 4 initial 227 (Intel® Fortran Compiler 19.0.4 build 227)
IRC post date 05/06/2019

This is the initial release of 2019 Update 4.  This was released in Linux* and Windows* packages only (no macOS* release).
This compiler is only available in the Intel® Registration Center in packages for:

  1. Intel® Parallel Studio XE Composer Edition for Fortran and C++  Linux, 2019 Update 4 227
  2. Intel® Parallel Studio Composer Edition for Fortran and C++ Windows, 2019 Update 4 228

This version provides initial support for VS2019 Integrations and includes certain functional and security updates.  We recommend updating for these functional and security updates. The default version "Update 4 Eng/Jpn" build should be used as it is the latest Update 4 compiler (see above).  If you are macOS* user there was no "Update 4 initial" compiler release (see Update 4 Eng/Jpn above).

IRC Links: Download the "Update 4 initial" compilers with the links below:

These packages contain both the Intel® C++ Compiler and the Intel® Fortran Compiler.  During installation you can select one or both compilers using the CUSTOM installation options.

For your next steps, use this table and the notes that follow the table:

2019 U4 Initial Release Decision Matrix

  1. If you are a licensed user of Intel Parallel® Studio XE Composer Edition for Fortran and C++ (Linux* or Windows*) you can find the "Update 4 initial" compiler in your Downloads in Intel® Registration Center.  It is not the default for Update 4.  Use the Prior versions pull-down selector to find this "Update 4 227 or 228" release.
  2. If you are a licensed user of CLUSTER Edition or PROFESSIONAL Edition you will not see the download for this package in your IRC Products downloads list.  Use the IRC LINKS above to directly download the package for your OS.  Your existing license for CLUSTER Edition or PROFESSIONAL Edition will work with the U4 initial packages and compilers.
  3. Licensed users of the Composer Edition for Fortran, or the Composer Edition for C++, use the IRC LINKS above to directly download the package for your OS. You will also need a new license which we will provide for the combined C++ and Fortran product Intel® Parallel Studio XE Composer Edition for Fortran and C++ (for your OS) - visit Technical Support and request your license.  Make sure to indicate Linux* or Windows* or both.  Again, this does not apply to macOS*. 

Changes in this version:

Changes in Update 3 (Intel® Fortran Compiler 19.0.3)

  • Previous compiler versions erroneously permitted a PRIVATE or SEQUENCE statement to appear prior to the declaration of any type parameters in a derive type declaration.  Intel® Fortran Compiler 19.0.3 no longer permits this behavior.
  • Corrections to reported problems

Changes in Update 2 (Intel® Fortran Compiler 19.0.2)

  • Intel® Fortran Compiler 19.0 Update 2 includes functional and security updates. Users should update to the latest version.

Changes in Update 1 (Intel® Fortran Compiler 19.0.1)

  • New code names supported by -[a]x, -mtune and -march options
    • code names supported : cascadelake, kabylake, coffeelake, amberlake, whiskeylake
  • Value safe simd options for !$OMP SIMD directive
  • First update with Japanese Localization
  • Corrections to reported problems

Changes since Intel® Fortran Compiler 18.0 (New in Intel® Fortran Compiler 19.0.0)

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System Requirements

For an explanation of architecture names, see Intel® Architecture Platform Terminology

  • A PC based on an Intel® 64 architecture processor supporting the Intel® Streaming SIMD Extensions 2 (Intel® SSE2) instructions (Intel® 2nd Generation or newer Generation of Intel® Core™ i3, i5, or i7 processors and Intel® Xeon® E3 or E5 processor family, or compatible non-Intel processor)
    • Development of 64-bit applications, and those that offload work to Intel® Xeon Phi™ processors, is supported on a 64-bit version of the OS only.  Development of 32-bit applications is supported on a 64-bit version of the OS only.
    • Development for a 32-bit on a 64-bit host may require optional library components (ia32-libs, lib32gcc1, lib32stdc++6, libc6-dev-i386, gcc-multilib, g++-multilib) to be installed from your Linux distribution.
  • For the best experience, a multi-core or multi-processor system is recommended
  • 2GB of RAM (4GB recommended)
  • 4GB free disk space for all features
  • For Intel® Xeon Phi™ x200 product family development/testing:
    • Intel® Xeon Phi™ processor x200 product family (formerly code named Knights Landing)
    • Intel® Xeon Phi™ Processor Software for Intel® Xeon Phi™ processor x200 product family
  • For development of IA-32 or Intel® 64 architecture applications, one of the following Linux distributions (this is the list of distributions tested by Intel; other distributions may or may not work and are not recommended - please refer to Technical Support if you have questions):
    • Debian* 8.0, 9.0
    • Fedora* 27, 28
    • Red Hat Enterprise Linux* 6, 7
    • SuSE LINUX Enterprise Server* 12 (SP3), 15
    • Ubuntu* 18.04 LTS, 17.10
    • CentOS 7.1, 7.2
    • Intel® Cluster Ready
  • Linux Developer tools component installed, including gcc, g++ and related tools. (this is the list of component versions tested by Intel; other versions may or may not work and are not recommended - please refer to Technical Support if you have questions
    • gcc 4.4 to gcc 7
    • binutils 2.20 to binutils 2.29
  • Library is required in order to use the -traceback option.  Some Linux distributions may require that it be obtained and installed separately.


  • The Intel® compilers are tested with a number of different Linux distributions, with different versions of gcc. The version of glibc you use must be consistent with the version of gcc in use. For best results, use only the gcc versions as supplied with distributions listed above.
  • Compiling very large source files (several thousands of lines) using advanced optimizations such as -O3, -ipo and -qopenmp, may require substantially larger amounts of RAM.
  • Some optimization options have restrictions regarding the processor type on which the application is run. Please see the documentation of these options for more information.

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Intel® Xeon Phi™ Processor Software

Intel® Xeon Phi™ Processor Software is a set of software and utilities that enable functionalities of the Intel® Xeon Phi™ Processor. The Intel® Xeon Phi™ Processor Software may be installed before or after installing the Intel® Fortran Compiler, if you will be developing applications that use Intel® Xeon Phi™ processor product family x200 (formerly code named Knights Landing).

Using the latest version of Intel® Xeon Phi™ Processor Software is recommended. Refer to the Intel® Xeon Phi™ Processor Software documentation for details.

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How to install the Intel® Fortran Compiler

Installation instructions are shipped with all Intel® Software Development Products as part of the documentation. Installation guides for the latest Intel® Parallel Studio XE version are also available online. Please check Intel® Parallel Studio XE getting started page for installation guides. Note that link to Installation Guide is also available on Intel® Registration Center while downloading required installation package. Please refer to Installation FAQ for more details.

How to use the Intel® Fortran Compiler

Intel® Parallel Studio XE 2019: Getting Started with the Intel® Fortran Compiler 19.0 for Linux* at <install-dir>/documentation_2019/en/compiler_f/ps2019/get_started_lf.htm contains information on how to use the Intel® Fortran Compiler.

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Product documentation is linked from <install-dir>/documentation_2019/en/compiler_f/ps2019/get_started_lf.htm.

Offline Core Documentation Removed from the Installed Image

Offline core documentation is removed from the Intel® Parallel Studio XE installed image. The core documentation for the components of Intel® Parallel Studio XE are available at the Intel® Software Documentation Library for viewing online. Offline documentation for older versions is also available from the Intel® Software Development Products Registration CenterProduct List > Intel® Parallel Studio XE Documentation.

User and Reference Guides, What's New and Release Notes, Installation Guides

Refer to the Intel® Parallel Studio XE Support – Documentation for additional User and Reference Guides, What’s New and Release Notes, and Installation Guides.

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Japanese Language Support

Japanese language support is not provided with this release of the product.

If you wish to use Japanese-language support on an English-language operating system, or English-language support on a Japanese-language operating system, you will find instructions at Changing Language Setting to see English on a Japanese OS environment or Vice Versa on Linux*.

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Intel-provided debug solutions

Intel®-provided debug solutions are based GNU* GDB.  Please see  Intel® Parallel Studio 2019 Composer Edition Fortran - Debug Solutions Release Notes for further information.

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Product samples are now available online at Intel® Software Product Samples and Tutorials.

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Redistributable Libraries

Refer to the Redistributable Libraries for Intel® Parallel Studio XE for more information.

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Technical Support

Register your license at the Intel® Software Development Products Registration Center. Registration entitles you to free technical support, product updates and upgrades for the duration of the support term.

For information about how to find Technical Support, Product Updates, User Forums, FAQs, tips and tricks, and other support information, please visit:

Note: If your distributor provides technical support for this product, please contact them for support rather than Intel.

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In general, object code and modules compiled with earlier versions of Intel Fortran Compiler for Linux* (8.0 and later) may be used in a build with version 19.0. Exceptions include:

  • Sources that use the CLASS keyword to declare polymorphic variables and which were built with a compiler version earlier than 12.0 must be recompiled.
  • Objects built with the multi-file interprocedural optimization (-ipo) option must be recompiled with the current version.
  • Objects that use the REAL(16), REAL*16, COMPLEX(16) or COMPLEX*32 datatypes and which were compiled with versions earlier than 12.0 must be recompiled.
  • Objects built for the Intel® 64 architecture with a compiler version earlier than 10.0 and that have module variables must be recompiled.  If non-Fortran sources reference these variables, the external names may need to be changed to remove an incorrect leading underscore.
  • Modules that specified an ATTRIBUTES ALIGN directive outside of a derived type and were compiled with versions earlier than 11.0 must be recompiled.  The compiler will notify you if this issue is encountered.
  • Modules that specified an ATTRIBUTES ALIGN directive inside a derived type declaration cannot be used by compilers older than 13.0.1.
  • The implementation of the Fortran 2008 submodules feature required extensive changes to the internal format of binary .mod files. Therefore module files created by the version 16.0 or newer Fortran compiler cannot be used with version 15.0 or older Fortran compilers.
  • Objects/libraries compiled/built for the Intel® Xeon Phi™ x100 product family are not compatible with objects/libraries compiled/built for the Intel® Xeon Phi™ x200 product family. 

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Stack Alignment Change for REAL(16) and COMPLEX(16) Datatypes

In versions prior to 12.0, when a REAL(16) or COMPLEX(16) (REAL*16 or COMPLEX*32) item was passed by value, the stack address was aligned at 4 bytes.  For improved performance, the version 12 and later compilers align such items at 16 bytes and expects received arguments to be aligned on 16-byte boundaries. This change is also compatible with gcc.

This change primarily affects compiler-generated calls to library routines that do computations on REAL(16) values, including intrinsics. If you have code compiled with earlier versions and link it with the version 12 libraries, or have an application linked to the shared version of the Intel run-time libraries, it may give incorrect results.

In order to avoid errors, you must recompile all Fortran sources that use the REAL(16) and COMPLEX(16) datatypes if they were compiled by compiler versions earlier than 12.0.

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New and Changed Features

The Intel® Fortran Compiler supports all features from the Fortran 2008 standard.

Please refer to the Fortran 2008 Standard (PDF) and the Fortran 2018 Standard (PDF) if necessary.

Intel® Parallel Studio XE 2019 Update 4 requires version 2.9 or higher of the Intel Software License Manager for floating licenses

The Intel® Software License Manager has been updated to version 2.9 for this release. You must upgrade to this version before installing Intel Parallel Studio XE 2019 Update 4 with a floating license. Please refer for more details:

Intel® Software License Manager Download
Intel® Software License Manager Release Notes

Features from Fortran 2018

  • Coarray events
  • Intrinsic function coshape
  • Default accessibility for entities accessed from a module
  • Import Enhancements
  • All standard proceduress in ISO_C_BINDING other than C_F_POINTER are now PURE 

Features from OpenMP*

  • User-Defined Reductions from the OpenMP* 4.5 specifications are now supported:
    !$omp declare reduction(reduction-identifier: type-list : combiner) [initializer-clause]
  • The F2008 standard added the BLOCK/ENDBLOCK construct. It is now allowed to use this construct inside an OMP region.
  • ASSERT clause for !$OMP SIMD directive
    Directs the compiler to assert when the vectorization fails. Similar to deprecated !DIR$ SIMD ASSERT.

New and Changed Directives

  • New clause for dynamic alignment in the VECTOR directive:
    The compiler generates a peel loop for the specified pointer. If no pointer is specified, the compiler automatically decides for which pointer to generate aligned loads and stores, or else doesn’t generate a peel loop. With the nodynamic_align clause, the compiler will not generate a peel loop.
  • New clause for vector length in VECTOR directive:
     !DIR$ VECTOR VECTORLENGTH(vl1, vl2, ..., vln) 
    Vectorizer chooses best vector length from the list according to cost model. If all vector lengths from the list are not profitable, the loop remains scalar. 

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New and Changed Compiler Options

Please refer to the compiler documentation for details

For a list of deprecated compiler options, see the Compiler Options section of the documentation.

Value safe simd options for !$OMP SIMD directive

!$OMP SIMD directive overrides FP value and exception safe settings. Following options introduced in 19.0 Update 1 change that legacy behavior and produce value and exception safe code even for SIMD loops:
  • -q[no-]simd-honor-fp-model: Tells the compiler to obey the selected floating-point model when vectorizing SIMD loops
  • -q[no-]simd-serialize-fp-reduction: Tells the compiler to serialize floating-point reduction when vectorizing SIMD loops.
Note that these options don't  affect auto-vectorization of loops. Please refer to the compiler documentation for more details.

-qopenmp-simd is on by default

-qopenmp-simd option enables OpenMP* SIMD compilation. It is set by default now. In order to disable it please use -qno-openmp-simd- option explicitly.

New -check:shape and -warn:shape options

These switches tell the compiler to produce errors or warnings when shapes of arrays do not match on assignments. This check is done for assignments only (and implicit assignments resulting from an allocate with source= syntax). 

New -fcf-protection option

This option enables Control-flow Enforcement Technology (CET) protection, which defends your program from certain attacks that exploit vulnerabilities. It is an alias to existing -qcf-protection option. -fcf-protection requires -mibt (for -fcf-protection=branch) or -mshstk (for -fcf-protection=return) to present in command line. 


This option is supported in versions 19.0 update 8 of the compiler and above. The details about this option can be found in the Intel® Fortran Compiler 19.1 Developer Guide and Reference. To find more information, see


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Support Deprecated

-rcd option

Loop Profiler

The Loop Profiler feature is deprecated in the 19.0 compiler and will be removed in future compiler release. The following compiler options related to Loop Profiler are deprecated and will be removed in future compiler release: -profile-loops=keyword, -profile-loops-report=value -profile-functions, -guide-profile.

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Support Removed

Installation on 32-bit hosts has been removed

Installation on 32-bit hosts was removed in  Intel® Parallel Studio XE 2018 versions. Support for generating code for 32-bit targets is supported on 64-bit hosts (only) via compiler option -m32.

Intel® Xeon Phi™ x100 product family coprocessor (formerly code name Knights Corner) is not supported

The Intel® Xeon Phi™ x100 product family coprocessor (formerly code name Knights Corner) was officially announced end of life in January 2017.  As part of the end of life process, the support for this family will only be available in the Intel® Parallel Studio XE 2017 version.  Intel® Parallel Studio XE 2017 will be supported for a period of 3 years ending in January 2020 for the Intel® Xeon Phi™ x100 product family.  Support will be provided for those customers with active support.

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Known Issues

Certain uses of OMP THREADPRIVATE with COMMON block name not diagnosed per OpenMP* 4.5 rules

The OpenMP* 4.5 rules states that if a threadprivate directive specifying a common block name appears in one program unit, then such a directive must also appear in every other program unit that contains a COMMON statement specifying the same name. It must appear after the last such COMMON statement in the program unit.  The Intel Fortran compiler does not properly diagnose this.

For example, the following program does not conform to the OpenMP* 4.5 specification and ifort does not diagnose and issue an error for the COMMON statements following the OMP THREADPRIVATE statement according to the rule above.

    COMMON /common_blk1/x 
    !$OMP THREADPRIVATE(/common_blk1/) 

    COMMON /common_blk1/y 
    COMMON /common_blk1/z


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Fortran 2008 and Fortran 2018 Feature Summary

The Intel® Fortran Compiler now supports all features from the Fortran 2008 standard. The Intel® Fortran Compiler also supports features from the proposed draft Fortran 2018 standard.  Additional features will be supported in future releases. Features from the proposed Fortran 2018 standard supported by the current version include:

  • Assumed type (TYPE(*))
  • Assumed rank (DIMENSION(..))
  • Relaxed restrictions on interoperable dummy arguments
  • C include file ISO_Fortran_binding.h for use by C code manipulating “C descriptors” used by Fortran
  • Coarray events
  • Intrinsic function coshape
  • Default accessibility for entities accessed from a module
  • Import Enhancements
  • All standard proceduress in ISO_C_BINDING other than C_F_POINTER are now PURE 

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Disclaimer and Legal Information

Optimization Notice
Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice. Notice revision #20110804


Intel may make changes to specifications and product descriptions at any time, without notice. Designers must not rely on the absence or characteristics of any features or instructions marked "reserved" or "undefined." Intel reserves these for future definition and shall have no responsibility whatsoever for conflicts or incompatibilities arising from future changes to them. The information here is subject to change without notice. Do not finalize a design with this information.

The products described in this document may contain design defects or errors known as errata which may cause the product to deviate from published specifications. Current characterized errata are available on request.

Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing your product order.

Copies of documents which have an order number and are referenced in this document, or other Intel literature, may be obtained by calling 1-800-548-4725, or go to: 

Intel processor numbers are not a measure of performance. Processor numbers differentiate features within each processor family, not across different processor families. Go to:

The Intel® Fortran Compiler is provided under Intel’s End User License Agreement (EULA). 

Please consult the licenses included in the distribution for details.

Intel, the Intel logo, the Intel Inside logo, Xeon, and Intel Xeon Phi are trademarks of Intel Corporation or its subsidiaries in the U.S. and/or other countries.

* Other names and brands may be claimed as the property of others.

Copyright © 2018 Intel Corporation. All Rights Reserved.

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