C++ Support in Embedded Studio

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Embedded Studio supports application development in C and C++. Its C runtime library, based on emRun, provides all fundamentals, tweaked for fastest speed or smallest size. In addition, the C++ library provides all required features for efficient C++ applications.

The C++ library adds:

  • C++ header files to wrap up their C equivalents. e.g. cmath to math.h.
  • C++-specific names and functions and mangled names for math.h. e.g. classification (isinf) and comparison (isless) functions, and cosf to cos(float) / cos to cos(double).
  • C++ header files for exception, new, typeinfo.
  • C++ unwinding library. Functions used for target unwinding, such as to implement exceptions.
  • The C++ ABI library. Low-level support for standard C++ libraries.
  • The C++ standard library.

This article describes how to enable the C++ libraries in Embedded Studio to use C++ library functions in target applications.

How to use the C++ Library

Note: For libcxx, Embedded Studio V5.60 or later is required.

Library installation steps (only necessary until ES V7.20)

The C++ standard library is based on the embedded C++ subset of the "libc++" C++ Standard Library.

To limit download and installation size of Embedded Studio, the library is supplied as additional packages for the supported target architectures. To enable the library in a project, only the common package needs to be installed. Embedded Studio takes care of downloading the specific packages if required.

  • Open the package manager under Tools -> Package Manager...
    • Make sure that you have the latest package list loaded to avoid download errors. To refresh the list manually you will find a refresh button in the top right corner of the package manager. The mouse over tool tip shows "Refresh Package List".
  • Select the "ARM libcxx Library Package [Common]" or "RISCV libcxx Library Package [Common]" for installation.
Package Manager
  • Optional: Select the specific libcxx Library Packages for your target architecture(s) for installation.
    • 'If not done, Embedded Studio will download the specific package for your project. See next steps.'
  • Press Next to continue the download and installation.

The library is now ready to use and can be enabled in new and existing projects.

Generic project setup steps

  • Open or create a project.
  • Option the project options and go to Code -> Libraries.
  • In "libcxx Library" select "Yes" or "Yes (No Exceptions)".
    • Optional, if you select Yes and you are using std functions that could throw exceptions make sure that project option "Code > Code Generation > Enable Exception Support" is set to Yes
Project Options
  • Press OK to save the project options.
  • If the specific package for your project has not been installed, yet, Embedded Studio prompts to download and install the package now.
    • Press Yes.
    • Press Next to continue the download and installation.
Package Prompt

The project is now configured to use the C++ standard library. Include the necessary headers and start using the library functions.

Enabling Exception Support

To enable exception support in your C++ project the following must be considered:

  • Make sure your library is installed as explained above. (Project option libcxx Library = Yes)
  • Set project option "Code > Code Generation > Enable Exception Support" to Yes.
  • Make sure that sections readonly and readexec are placed in your linker script.

Changing the C++ standard

Per default C++ support is set to gnu++98. If you are using more modern features of C++ make sure to change the standard to the respective version in project options under Code->Compiler->C++ Language Standard