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The C++ extension settings are highly configurable. This article explains the schema for the c_cpp_properties.json file. For general information about settings in VS Code, refer to Configure settings, as well as the Variables reference and Default VS Code Settings.

Looking to get started with configuring your C++ project? Begin with configure Intellisense.

Example of variables

The following JSON snippet is an example configuration for c_cpp_properties.json. You only need to include relevant variables in your JSON file, and any missing fields are filled in with their default values by the C++ extension.

{
  "env": {
    "myIncludePath": ["${workspaceFolder}/include", "${workspaceFolder}/src"],
    "myDefines": ["DEBUG", "MY_FEATURE=1"]
  },
  "configurations": [
    {
      "name": "Mac",
      "compilerPath": "/usr/bin/clang++",
      "intelliSenseMode": "macos-clang-x64",
      "includePath": ["${myIncludePath}", "${workspaceFolder}/**"],
      "defines": ["${myDefines}"],
      "cStandard": "c17",
      "cppStandard": "c++20",
      "macFrameworkPath": ["/System/Library/Frameworks", "/Library/Frameworks"],
      "browse": {
        "path": ["${myIncludePath}", "${workspaceFolder}"]
      }
    }
  ],
  "version": 4,
  "enableConfigurationSquiggles": true
}

Top-level properties

• env: An array of user-defined variables that are available for substitution in the configurations via the standard environment variable syntax: ${<var>} or ${env:<var>}. Strings and arrays of strings are accepted.

• configurations: An array of configuration objects that provide the IntelliSense engine with information about your project and your preferences. By default, the extension creates a configuration for you based on your operating system. You can also add more configurations.

• version: We recommend that you don't edit this field. It tracks the current version of the c_cpp_properties.json file, so that the extension knows what properties and settings should be present and how to upgrade this file to the latest version.

• enableConfigurationSquiggles: Set to true to report errors detected in c_cpp_properties.json file to the C++ extension.

Configuration properties

• name: A user-friendly name that identifies a configuration. Linux, Mac, and Win32 are special identifiers for configurations that are autoselected on those platforms. The Status Bar in VS Code shows you which configuration is active. You can also select the label in the Status Bar to change the active configuration.

• compilerPath: The full path to the compiler you use to build your project, for example /usr/bin/gcc, to enable more accurate IntelliSense. The extension queries the compiler to determine the system include paths and default defines to use for IntelliSense.

  Putting "compilerPath": "" (empty string) skips querying a compiler. This is useful if your preferred compiler doesn't support the arguments that are used for the query, as the extension defaults to any supported compilers it can find (like MSVC). Leaving out the compilerPath property does not skip the query.

• compilerArgs: Compiler arguments to modify the includes paths or defines used, for example -nostdinc++, -m32, etc. Arguments that take additional space-delimited arguments should be entered as separate arguments in the array, for example, for --sysroot <arg> use \"--sysroot\", \"<arg>\".

• intelliSenseMode: The IntelliSense mode to use that maps to an architecture-specific variant of MSVC, gcc, or Clang. If not set or if set to ${default}, the extension chooses the default for that platform.

  Platform defaults:

  • Windows: windows-msvc-x64
  • Linux: linux-gcc-x64
  • macOS: macos-clang-x64

  IntelliSense modes that only specify <compiler>-<architecture> variants (for example, gcc-x64) are legacy modes and are automatically converted to the <platform>-<compiler>-<architecture> variants based on the host platform.

• includePath: An include path is a directory of header files that are included by a source file. For example, a source file contains the include directive #include "myHeaderFile.h", adding the path of this header file to the includePath. Specify a list of paths for the IntelliSense engine to use while searching for included header files. Searching on these paths is not recursive. Specify /** at the end of the path to indicate recursive search. For example, ${workspaceFolder}/** searches through all subdirectories while ${workspaceFolder} will not. If you are on Windows with Visual Studio installed, or if a compiler is specified in the compilerPath setting, the system include paths should not be listed here.

• defines: A list of preprocessor definitions for the IntelliSense engine to use while parsing files. Optionally, use = to set a value, for example VERSION=1.

• cStandard: The version of the C language standard to use for IntelliSense. For example, c17, gnu23, or ${default}. Note: GNU standards are only used to query the set compiler to get GNU defines, and IntelliSense emulates the equivalent C standard version.

• cppStandard: The version of the C++ language standard to use for IntelliSense. For example, c++20, gnu++23, or ${default}. Note: GNU standards are only used to query the set compiler to get GNU defines, and IntelliSense emulates the equivalent C++ standard version.

• configurationProvider: The ID of a VS Code extension that can provide IntelliSense configuration information for source files. For example, use the VS Code extension ID ms-vscode.cmake-tools to provide configuration information from the CMake Tools extension. If you specified a configurationProvider, the configuration it provides takes precedence over your other settings in c_cpp_properties.json.

  A configurationProvider candidate extension must implement vscode-cpptools-api.

• mergeConfigurations: Set to true to merge include paths, defines, and forced includes with those from a configuration provider.

• windowsSdkVersion: The version of the Windows SDK include path to use on Windows, for example 10.0.17134.0.

• macFrameworkPath: A list of paths for the IntelliSense engine to use while searching for included headers from Mac frameworks.

• forcedInclude: A list of files that should be included before any text in the source file is processed. Files are included in the order listed.

• compileCommands: An array of paths that contain the full path to the compile_commands.json file for the workspace. If there is a matching entry in compile_commands.json for a file open in the editor, that command line is used to configure IntelliSense for that file, instead of the other fields of c_cpp_properties.json. For more information about the file format, see the Clang documentation. Some build systems, such as CMake, simplify generating this file.

• dotConfig: A path to a .config file, created by the Kconfig system. The Kconfig system generates a file with all the defines needed to build a project. Examples of projects that use the Kconfig system are the Linux Kernel and NuttX RTOS.

• customConfigurationVariables: Custom variables that can be queried through the command ${cpptools:activeConfigCustomVariable} to use for the input variables in launch.json or tasks.json.

• browse: The set of properties used in conjunction with IntelliSense to identify all symbols in your code base. These properties are used by features such as Go to Definition/Declaration, global symbol search, or when the "default" IntelliSense engine is unable to resolve the #includes in your source files.

• recursiveIncludes: A set of properties used to configure how the extension processes an includePath entry that specifies a recursive search.

Browse properties

• path: A list of paths who's source files are parsed to be used in global symbol searches. If omitted, includePath is used as the path. Searching on these paths is recursive by default. Specify * to indicate nonrecursive search. For example, ${workspaceFolder} searches through all subdirectories while ${workspaceFolder}/* does not.

• limitSymbolsToIncludedHeaders: When true, the Tag Parser only parses header files that are directly or indirectly included by a source file in ${workspaceFolder}. When false, the Tag Parser parses all code files found in the paths specified in the browse.path list.

• databaseFilename: The path to the generated symbol database. This property instructs the extension to save the workspace symbol database somewhere other than the workspace's default storage location. If a relative path is specified, it is made relative to the workspace's default storage location, not the workspace folder itself. The ${workspaceFolder} variable can be used to specify a path relative to the workspace folder (for example ${workspaceFolder}/.vscode/browse.vc.db)

Recursive includes properties

• reduce: When a recursive includePath entry is expanded, it can result in a very large set of include paths for IntelliSense to process when resolving #include statements in your source files. Sending a large set of include paths to the IntelliSense compiler can have an impact on the performance of IntelliSense on some systems. By default, the extension will reduce the set of include paths to the smallest possible set by first tag parsing the source files to search for #include statements and determining which include paths are needed. This reduction process is the same behavior as the always option for this setting. This behavior trades off some initial overhead so that IntelliSense can potentially be faster later on. Setting this property to never will provide the full recursive expansion of include paths to the IntelliSense process. By not parsing any files up front, this behavior trades off potential performance later on to ensure IntelliSense can start up more quickly when source files are opened. In general, reducing the number of recursive include paths in your configuration might improve IntelliSense performance when a large number of paths are involved.

• priority: The priority of recursive include path searches when resolving #include statements. If set to beforeSystemIncludes, the recursive include paths are searched before system include paths. If set to afterSystemIncludes, the recursive include paths will be searched after system include paths. beforeSystemIncludes would more closely reflect the search order of a compiler leading to more predictability, while afterSystemIncludes might result in improved performance.

• order: Whether subdirectories of recursive includes are searched breadthFirst or depthFirst.

Supported variables

You can allow tasks.json or launch.json to query the current active configuration from c_cpp_properties.json. To do this, use the variable ${command:cpptools.activeConfigName} as an argument in a tasks.json or launch.json script.

Default VS Code settings

All default VS Code settings, such as C_Cpp.default.includePath, are supported in c_cpp_properties.json. The only exception is:

C_Cpp.default.systemIncludePath : string[]

This setting allows you to specify the system include path separately from the include path. However, the selected system include path that the C++ extension receives from the compiler is not passed to the IntelliSense process. This is only used in rare scenarios since it overwrites the standard compiler behavior, for example, if your compiler is not supported. Instead, use the setting compilerArgs and using the -isystem flag to specify system headers, which is a better solution in most scenarios.