Intel® C++ Compiler 19.1 for Windows* Host Release Notes for Intel® System Studio 2020

ID 788301
Updated 10/29/2020

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

Change History

Changes since Intel® C++ Compiler 19.1.2 (New in Intel® C++ Compiler 19.1.3)

  • Corrections to reported problems.

Changes since Intel® C++ Compiler 19.1.1 (New in Intel® C++ Compiler 19.1.2)

  • Corrections to reported problems.

Changes since Intel® C++ Compiler 19.1 (New in Intel® C++ Compiler 19.1.1)

  • Corrections to reported problems.

Changes since Intel® C++ Compiler 19.0 (New in Intel® C++ Compiler 19.1)

System Requirements

 Host Hardware Requirements

  • 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)
  • 2GB RAM (4GB recommended)
  • 4GB free disk space required for all product features and all architectures

 Host Software Requirements

  • Microsoft Windows* 10, Microsoft Windows Server* 2016, 2019 (Intel® 64 only).  

 Target Hardware Requirements

  • Development platform based on the Intel Atom® processor Z5xx, N4xx, N5xx, D5xx E6xx, N2xxx, D2xxx, Z2xxx, Z3xxx, E3xxx, S1xxx, C2xxx, C3xxx, Intel Atom® processor X Series, the Intel Atom® processor CE4xxx, CE53xx or the Intel® Puma6™ Media Gateway.
  • Alternatively development platform based on 4th, 5th, 6th,7th or 8th generation Intel® Core™ microarchitecture based Intel® Core™ processor or Intel® Xeon® Processor
  • Development targeting Intel® Quark™ processor X1xxx, D1xxx, D2xxx,  Intel® Quark™ SE C1xxx
  • Needed hard disk space
    • 13MB (IA-32) / 15MB (Intel® 64)

Target Software Requirements

The target platform should be based on one of the following environments:

  • SUSE* Linux* Enterprise Server 12, 15
  • Red Hat* Enterprise Linux* (RHEL) 7, 8
  • CentOS* 7, 8
  • Ubuntu* 18.04 LTS
  • Wind River* Linux* LTS 19
  • Yocto Project* 2.x, 3.x based environment

How to use the Intel® C++ Compiler

Intel System Studio 2020: Getting Started with the Intel® C++ Compiler 19.1* at <install-dir>\documentation_2020\en\compiler_c\iss2020\get_started_lc.htm contains information on how to use the Intel® C++ Compiler from the command line.


Product documentation is linked from <install-dir>\documentation_2020\en\.  Full documentation for all tool components is available at the Intel System Studio Documentation page.

Offline Core Documentation Removed from the Installed Image

The core documentation for the components of Intel® System Studio is available at the Intel® Software Documentation Library for viewing online. You can also download an offline version of the documentation from the Intel® Software Development Products Registration Center: Product List > Intel® System Studio Documentation.

Intel-provided debug solutions


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

Technical Support

If you did not register your compiler during installation, please do so 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.

New and Changed Features

The following features are new or significantly enhanced in this version.  For more information on these features, please refer to the documentation.

Access to Intel® C++ Compiler Based on the Modern LLVM* Framework, aka ICC NextGen

  • /Qnextgen compiler option invokes the Early Access ICC NextGen compiler. These options are only available for Windows* or Linux* ICC/ICL/ICPC drivers.  

C++20 features supported

  • The Intel® C++ Compiler 19.1 supports the following features under the /Qstd=c++20 (Windows*) or -std=c++20 (Linux*/macOS*) options:
    • std::is_constant_evaluated and __builtin_is_constant_evaluated

Features from OpenMP* 5.0

  • IF clause on SIMD directive
  • NONTEMPORAL clause on SIMD directive

Parallel STL for parallel and vector execution of the C++ STL

Intel(R) C++ Compiler is installed with Parallel STL, an implementation of the C++ standard library algorithms with support for execution policies.

Features/API changes

  • More algorithms support parallel and vector execution policies: find_first_of, is_heap, is_heap_until, replace, replace_if.
  • More algorithms support vector execution policies: remove, remove_if.
  • More algorithms support parallel execution policies: partial_sort.

To learn more, please refer to this article

Support Deprecated

Support Removed

  • Support for Android* target is removed
  • FreeBSD* support is removed  
  • Microsoft Windows* 7, Windows Server* 2008 R2 SP1, Windows Server* 2012 are not supported
  • Microsoft Windows* 7, Windows Server* 2008 R2 SP1, Windows Server* 2012 are not supported with Intel® C++ Compiler 19.1.
  • The Loop Profiler feature will be removed in future compilers.
    • The following compiler options related to Loop Profiler are deprecated and will be removed in future compilers
      • /Qprofile-loops=keyword
      • /Qprofile-loops-report=value
      • /Qprofile-functions
      • /Qguide-profile

Known Issues

  • Parallel STL

unseq and par_unseq policies only have effect with compilers that support '#pragma omp simd' or '#pragma simd. Parallel and vector execution is only supported for a subset of algorithms if random access iterators are provided, while for the rest execution will remain serial. Depending on a compiler, zip_iterator may not work with unseq and par_unseq policies.

  • Pointer Checker requires a dynamic runtime library

When using the -check-pointers option, the runtime library must be linked in. When using options like -static or -static-intel with -check-pointers, be aware that this dynamic library will be linked in regardless of your settings. See the article at Pointer Checker in ICC for more information.