IBM z/OS XL C/C++
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IBM z/OS XL C/C++ is a C/C++ compiler for z/OS based on the LLVM open-source Clang infrastructure.

The z/OS XL C/C++ compiler uses the C/C++ runtime environment and library of runtime services available with the Language Environment® and Runtime Library Extensions elements provided with z/OS. The compiler supports embedded CICS® and SQL statements in C/C++ source, simplifying the operation of C/C++ within CICS and Db2® environments. IBM Application Delivery Foundation for z/OS can be used with XL C/C++ to help accelerate the delivery of z/OS® applications.

IBM Open XL C/C++ is based on the LLVM open-source Clang infrastructure and supports current C/C++ language standards and the latest IBM z16™ servers. Open XL C/C++ is a web deliverable that current z/OS XL C/C++ clients on z/OS 2.4 or 2.5 can download at no charge.

Read about the next generation of IBM C/C++ compiler generally available on z/OS
Benefits Easily migrate applications to z/OS

Get support for C17, C18 and C++17 language standards. It uses the Clang command line interface, which significantly improves cross platform compatibility for C/C++ applications.

Increase return on investments

Optimize application performance with leading-edge optimization technology while leveraging the latest features of the IBM Z® servers.

Leverage system programming capabilities

Take advantage of the METAL option to simplify system programming by using C syntax to generate optimized low-level free-standing applications on z/OS.

IBM Open XL C/C++ compiler features Based on open-source LLVM framework

Fully incorporates the Clang and LLVM compiler infrastructure for C/C++. Combines open-source technology and IBM's strength in compiler optimization technology.

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Supports current C/C++ language standards

Supports up to C17, C18 and C++17 language standard features.

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Advanced optimization technology that supports the latest IBM Z server

Supports the hardware features in the latest IBM z16™ servers. Delivers hardware level capabilities directly to you through compiler options.

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Provides cross platform compatibility

Adopts the Clang command line interface, which improves cross platform compatibility for C/C++ applications on z/OS.

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Supports high-performance mathematical computing libraries

Supports the OpenBLAS library for high-performance mathematical computing.

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Supports 64-bit and runs on z/OS UNIX System Service

Use the advanced 64-bit compiler that supports EBCDIC and ASCII and generates AMODE 64 code, making it ideal for porting applications from distributed platforms.

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IBM z/OS XL C/C++ compiler features METAL C for system programming capabilities

Provides the METAL option to support system program development on z/OS. Target system programs written in Metal C to new IBM Z servers by recompiling to include optimizations for the target system.

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Support for program diagnosis and debug

Increases programmer productivity and code generation with a cost-effective way of diagnosing potential language semantics adherence. It is supported by debugging tools such as IBM Debug for z/OS and dbx.

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Industry standards support

Conforms to C89, C99, C++98, C++03, core C11, C++11 and C++14 standards, enabling porting for optimal performance. GNU C/C++ language extensions and compatibility optimize migration and programming.

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Support for automatic SIMDization optimization

Use automatic SIMDization or automatic vectorization optimization that uses single or multiple data (SIMD) instructions to automatically generate SIMD code without parallel programming.

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Advanced optimization technology

Use advanced compilation and optimization technology such as high-order transformation (HOT) loop, interprocedural analysis (IPA) and profile-directed feedback (PDF) for improved performance. 

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High-performance mathematical computing libraries

Use the Mathematical Acceleration Subsystem (MASS) and Automatically Tuned Linear Algebra Software (ATLAS) for accelerated execution of math and algebra functions used in business analytics.

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Integration with IBM Application Delivery Foundation for z/OS

Use the compiler to integrate IBM Developer for z/OS Enterprise Edition tools, which include IBM Debug for z/OS, IBM Fault Analyzer for z/OS and IBM Application Performance Analyzer for z/OS.

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Support for embedded CICS and SQL statements

Simplifies the operation of C/C++ within CICS and Db2 environments with support for embedded CICS and SQL statements in C/C++ source that are passed through without the need for a preprocessing step.

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Explore products

IBM Open XL C/C++ for z/OS

The newest C and C++ compiler on z/OS, supports the latest C/C++ language standards with the Clang interface for improved cross platform compatibility.

IBM z/OS XL C/C++

An advanced optimizing C and C++ compiler on z/OS that leverages the IBM Z architecture features. 

Entitled via IBM z/OS XL C/C++

A priced feature of z/OS

Clients need to enable the IBM z/OS XL C/C++ priced feature of z/OS

Monthly License Charge (MLC)

Clients who are currently running IBM z/OS XL C/C++ can download Open XL C/C++ at no charge

World-class IBM support

Monthly License Charge (MLC)

Contact your IBM representative for detailed pricing information

World-class IBM support

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Resources Code optimization with the IBM z/OS XL C/C++ Compiler

Read this document to learn about the capabilities that you can use to maximize the performance of your C/C++ applications.

Upgrading z/OS XL C/C++ compilers

Check out this paper which outlines the new features introduced in recent releases of the XL C/C++ compiler and their benefits.

SOS info utility for z/OS XL C/C++ compiler

Learn how to use the SOS info utility to obtain options information from an executable file without the need to produce and maintain listing files.

IBM’s next generation C/C++ compiler now available on z/OS

Learn more about this new C/C++ compiler and IBM’s strategy of adopting LLVM open-source infrastructure.

Using inline assembly for z/OS XL C/C++ compiler

Learn two ways to use high-level languages in low-level programming.

AutoSIMD compiler optimization for z/OS XL C/C++ programs

Learn about the AutoSIMD optimization introduced in the z/OS 2.2 XL C/C++ compiler.

Watch this video which introduces IBM z/OS XL C/C++, an advanced optimizing C and C++ compiler on z/OS that leverages the IBM Z architecture features.

Watch this video about the Metal C feature in the IBM z/OS XL C/C++ compiler.

Open XL C/C++ and XL C/C++ for z/OS documentation library

Check out this library which contains a collection of announcement letters and product documentation for Open XL C/C++ and XL C/C++ for z/OS.

Fix list for z/OS XL C/C++

Check out a complete listing of releases, refreshes, fix packs and interim fixes sorted by version for IBM z/OS XL C/C++.

Related products IBM XL C/C++ for z/VM

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IBM XL C/C++ for AIX

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IBM XL C for AIX

Learn more about a high-performance compiler for developing complex C programs on AIX® .

Next steps

Find out how you can use an advanced optimizing C and C++ compiler on z/OS to exploit the latest IBM Z architecture. 

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