# Introduction

This document is a reference for C/C++ programmers. It describes C and C++ compilers for the Qualcomm® Hexagon™ processor architecture. The compilers are based on the LLVM framework and are collectively
referred to as the *LLVM compilers*.

The LLVM compilers work with the Hexagon software development tools and utilities to provide a complete programming system for developing high-performance software.

The compilers run on the Windows and Linux platforms.

Note

The LLVM compilers are commonly referred to as *clang*.

## Conventions

Courier font is used for computer text and code samples, for example, `void foo()`. The following notation is used to define command syntax:

- Square brackets enclose optional items, for example, `[label]`.
- **Bold** indicates literal symbols for example, `[comment]`.
- The vertical bar character, `|`, indicates a choice of items.
- Parentheses enclose a choice of items for example, (`add | del`).
- An ellipsis, `...`, follows items that can appear more than once.

For example:

#define <name>(<parameter1>[, <parameter2>...]) <definition>
    logging (on|off)
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Where:

- `#define` is a preprocessor directive `<name>` is the name of a defined symbol.
- `<parameter1>` and `<parameter>` are macro parameters. The square brackets indicate that the second parameter is optional. The ellipsis indicates that the macro accepts more than parameters.
- `logging`` is an interactive compiler command.
- `on` and `off` are bold to show that they are literal symbols. The vertical bar indicates that they are alternative parameters of the logging command.

## Technical assistance

For assistance or clarification on information in this document, submit a case to Qualcomm Technologies, Inc. (QTI) at [https://support.qualcomm.com/](https://support.qualcomm.com/).

Last Published: Oct 06, 2026

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