{"id":20922,"date":"2018-09-18T16:13:10","date_gmt":"2018-09-18T16:13:10","guid":{"rendered":"https:\/\/devblogs.microsoft.com\/vcblog\/?p=20922"},"modified":"2019-05-17T08:05:04","modified_gmt":"2019-05-17T08:05:04","slug":"parallel-custom-build-tools-in-visual-studio-2017","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/cppblog\/parallel-custom-build-tools-in-visual-studio-2017\/","title":{"rendered":"Parallel Custom Build Tools in Visual Studio 2017"},"content":{"rendered":"

Many projects need to use additional tools during their build to generate sources for further compilation or perform other custom build tasks. VC projects have always supported Custom Build Tool integration, but it had some limitations. One of the popular requests on UserVoice is Allow custom build tools to run in parallel<\/a>. Another problem is that often custom build outputs need to be passed to other build tools (for instance, some tools can generate C\/C++ sources, which need to be passed to the compiler) and there was no easy way to specify that.<\/p>\n

To solve these problems, we added support for parallel execution of custom build tools and new options for easier build integration in Visual Studio 2017 15.8.<\/p>\n

Also, one of the most common build customizations is copying files. Before, we recommended using \u201cCustom Build Step\u201d or \u201cCustom Build Tool\u201d and specifying copy commands there. Now you can use simple Copy File options.<\/p>\n

Custom Build Tool Options<\/h3>\n

If you are familiar with Custom Build Tool usage, you can skip this section and go to New Custom Build Tool Options.<\/p>\n

Custom Build Tool options are not visible in the \u201cProject Properties\u201d until you have at least one file using \u201cCustom Build Tool\u201d as its \u201cItem Type\u201d. You can set it in the file\u2019s \u201cGeneral\u201d properties:<\/p>\n

\"Custom<\/a><\/p>\n

As for other tools, you can set \u201cCustom Build Tool\u201d properties for each file, but usually it is easier to set them at the project configuration level, so they apply to all files which use \u201cCustom Build Tool\u201d. Note that you can use MSBuild Well-known Item Metadata<\/a> there to specify file specific options. Unfortunately, you cannot use other item properties as they are not guaranteed to be defined before their usage.<\/p>\n

\"Custom<\/a><\/p>\n

Command Line<\/strong><\/p>\n

Specifies the command(s) to execute in cmd.exe. If you want several commands to be executed for the same file, you can add them to a script file or just enter them in the property editor, each command on a separate line:<\/p>\n

\"Custom<\/a><\/p>\n

Description<\/strong><\/p>\n

Specifies a message to be printed before execution of the command(s), optional. It is added as \u2018\u2019echo\u201d command, so if you want to use \u201c>\u201d symbol, it needs to be escaped: \u201c^>\u201d.<\/p>\n

Outputs<\/strong><\/p>\n

Specifies the output files the custom build tool generates.<\/p>\n

Additional Dependencies<\/strong><\/p>\n

Specifies any additional input files to use for the custom build tool. Required for incremental build.<\/p>\n

Link Objects<\/strong><\/p>\n

Specify whether the Inputs and outputs files with specific extensions (.obj, .lib, .res, .rsc) are passed to the linker.\nThis property was added in VS 2010 to maintain the behavior of pre-msbuild vc projects (VS 2009 and before) where file extensions determined which build action was performed on them.<\/p>\n

MSBuild is operating on items included into a particular named ItemGroup (Item Type), so we recommend using the new \u201cAdd Outputs to Item Type\u201d property instead.<\/p>\n

Treat Output As Content<\/strong><\/p>\n

Specify whether the output file is a deployable content. Only used in projects supporting packaging (Universal Windows).<\/p>\n

Content Root Folder<\/strong><\/p>\n

Content root folder to use for packaging.<\/p>\n

Execute After, Execute Before<\/strong><\/p>\n

Define when to execute Custom Build Tool and Custom Build Step commands. For historical reasons they are executed at the same time.\nThe options are using msbuild target names, which requires you to have some understanding of msbuild targets execution order during build. There is a long list of the targets in the dropdown you can select from and you can type the target name there as well, but usually you just need to select one of the following targets which represent 3 main steps of C++ build:<\/p>\n