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Language standard

Language standard supported by compiler

Model Configuration Pane: Code Generation

Description

The Language standard parameter specifies the language standard supported by your compiler.

Dependencies

  • C++03 is available for use only if you select C++ for the Language parameter.

  • When you change the value of the Language parameter, the Language standard is updated to C99 (ISO) for C and C++11 (ISO) for C++.

Settings

C99 (ISO) if Language is set to C or C++11 (ISO) if Language is set to C++ (default) | C89/C90 (ANSI) | C++03 (ISO)
C89/C90 (ANSI)

Generates code that conforms to the ISO®/IEC 9899:1990 C language standard.

C99 (ISO)

Generates code that conforms to the ISO/IEC 9899:1999 C language standard.

C++03 (ISO)

Generates code that conforms to the ISO/IEC 14882:2003 C++ language standard and is compatible with subsequent versions of C++, such as C++14 and C++17.

C++11 (ISO)

Generates code that conforms to the ISO/IEC 14882:2011 C++ language standard and is compatible with subsequent versions of C++, such as C++14 and C++17.

Tips

  • Before setting this parameter, verify that your compiler supports the standard you want to use. If you select a parameter value that your compiler does not support, compiler errors can occur.

    • For example, if you select C99 (ISO), the code generator implements minimal scoping in the generated code, which is not supported by C89/90 compilers.

  • If you are using a compiler that does not support ISO/IEC 9899:1999 C, set this parameter to C89/C90 (ANSI).

  • The build process checks whether the specified language standard and toolchain are compatible. If they are not compatible, a warning occurs during code generation and the build process continues.

  • If you use a Linux® GCC compiler for the build process, the software uses the compiler default language standard to compile the generated code. Depending on the compiler version, the default language standard varies. For more information, see C++ Standards Support in GCC.

    For example, if you use the GCC compiler version 8.x and set the parameter Language standard to C++03, the software uses the C++14 language standard during compilation. The usage of C++14 enables building the generated code that integrates custom code that uses C++11 or C++14 features.

    If you want to enforce the language standard specified in the parameter on the compilation process, then you must add language standard specific compiler flags manually. If your model is configured to use a toolchain for building code, use this procedure:

    1. In the Configuration Parameters dialog box, set Build configuration to Specify.

    2. Under Toolchain details, at the end of the C Compiler and C++ Compiler Options field entries, manually add these compiler flags:

      • When the Language standard is set to C99(ISO), add the flag -std=c99 -pedantic.

      • When the Language standard is set to C89/90(ANSI), add the flag -ansi -pedantic -Wno-long-long. Depending on model configuration, the build process might include a coder typedef header file that contains the definition 'typedef unsigned long long ulonglong_T'. -Wno-long-long suppresses the C90 compiler warning about the use of the long long type.

      • When the Language standard is set to C++03, add the flag -std=c++03 -pedantic.

      • When the Language standard is set to C++11, add the flag -std=c++11 -pedantic.

Recommended Settings

ApplicationSetting
DebuggingNo impact
TraceabilityNo impact
EfficiencyValid library
Safety precautionNo impact

Programmatic Use

Parameter: TargetLangStandard
Type: character vector
Value: 'C89/C90 (ANSI)' | 'C99 (ISO)' | 'C++03 (ISO)' | 'C++11 (ISO)'
Default: For C, 'C99 (ISO)'; for C++ 'C++11 (ISO)'

Version History

Introduced in R2014a

See Also

Topics