Base, Debug, and Release are the three default build configurations. Base acts as a base set of option values that is used in all the configurations you subsequently create. The Debug configuration enables optimization and debugging, as well as setting specific syntax options. The Release configuration doesn't produce symbolic debugging information as well as the code is not generated for TRACE and ASSERT calls, meaning the size of your executable is reduced. 

You can change option values in any configuration, including Base. You can delete the Debug and Release configurations, but you cannot delete the Base configuration.  

You can change option values in any configuration, including Base. You can delete the Debug and Release configurations, but you cannot delete the Base configuration.

Every project has an active build configuration associated with it, as well as any number of other inactive build configurations that you have created.  

The active build configuration is used in Compile and Build commands for the project. Use the Build Configuration Manager to specify the active configuration for a selected project or project group (choose ProjectConfiguration Manager).

Each configuration, except Base, is based on another configuration from which it inherits its values. The Debug and Release configurations inherit their values from Base.  

You can, in turn, create a new configuration based on any configuration, and the new configuration inherits values from its parent. After creating a configuration, you can change its values to whatever you want, and you can make it the active configuration for a project or projects. You can also delete any configuration except Base. 

Unless it is changed, a configuration inherits its option values from its parent configuration. This inheritance is not static: if the parent configuration changes, so do its children for all inherited values. 

The default value of an option is its value in its parent configuration. You can revert an option to its default value.

You can also save a configuration's option values to a file as a named option set using a file save dialog. You can apply option set values to any configuration in any project. 

Note that a configuration is different from an option set, though they are related. Both consist of sets of option values. The main distinction is that configurations are associated with projects, whereas option sets are saved in files independent of projects. Build configuration values are stored in the project file, so saving a project saves changes to configurations, but option sets are unaffected. Changing a project's configurations and adding or deleting configurations does not affect option sets. Similarly, saving option sets does not change configurations.  

The Build Configuration drop-down menu lists configurations for that project—not option sets. Each project has its own list of configurations, independent of other projects. However, you can access any option set from any project.

Note that configurations and option sets may not contain values for all possible project options--they contain only the options that are different from the parent configuration. Base also does not contain values for all possible options.  

If an option value is not in a configuration, the IDE looks in its parent configuration, then the parent's parent configuration, and so on. If not found in any of the configurations in the inheritance chain, the value comes from the appropriate tool that is being configured.  

For instance, if a configuration inheritance chain does not include a value for a particular compiler option, the default value is specified by the compiler itself. When you save a configuration or option set, only its values are saved--not values for every option.

Some options that contain a list of items, such as defines or paths, have a Merge check box.  

If Merge is checked, the IDE merges the option's list with that of its immediate ancestor's configuration's list for that option. Note that the IDE does not actually change the contents of the option, but acts as if the list included the ancestor's list. If the ancestor's Merge check box is also checked, the IDE merges this ancestor's list for that option, and so on up the inheritance chain.  

If Merge is unchecked, the IDE uses only the items in the option.

Some options available in previous releases are no longer available, except possibly through the tool option flags. See Unavailable Options for more information.

MSBuild Overview 

Creating Named Build Configurations (C++) 

Applying the Active Build Configuration 

Working With Named Option Sets 

Setting C++ Project Options 

Unavailable Options