Development Reference Guides

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Pragmas

Pragmas are directives that provide instructions to the compiler for use in specific cases. For example, you can use the
novector
pragma to specify that a loop should never be vectorized. The keyword
#pragma
is standard in the C++ language, but individual pragmas are machine-specific or operating system-specific, and vary by compiler.
Some pragmas provide the same functionality as compiler options. Pragmas override behavior specified by compiler options.
Some pragmas are available for both Intel® and non-Intel microprocessors but they may perform additional optimizations for Intel® microprocessors than they perform for non-Intel microprocessors. Refer to the individual pragma name for detailed description.
The
Intel® oneAPI
DPC++/C++
Compiler
pragmas are categorized as follows:
  • Intel-specific Pragmas - pragmas developed or modified by Intel to work specifically with the
    Intel oneAPI
    DPC++/C++
    Compiler
  • Intel Supported Pragmas - pragmas developed by external sources that are supported by the
    Intel oneAPI
    DPC++/C++
    Compiler
    for compatibility reasons

Using Pragmas

You enter pragmas into your C++ source code using the following syntax:
#pragma <pragma name>

Individual Pragma Descriptions

Each pragma description has the following details:
Section
Description
Short Description
Contains a brief description of what the pragma does.
Syntax
Contains the pragma syntax.
Arguments
Contains a list of the arguments (parameters).
Description
Contains a detailed description of what the pragma does.
Example
Contains typical usage example/s.
See Also
Contains links or paths to other pragmas or related topics.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.