{"id":30425,"date":"2022-04-20T20:20:17","date_gmt":"2022-04-20T20:20:17","guid":{"rendered":"https:\/\/devblogs.microsoft.com\/cppblog\/?p=30425"},"modified":"2022-04-20T20:23:17","modified_gmt":"2022-04-20T20:23:17","slug":"whats-new-for-c-debugging-in-visual-studio-code","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/cppblog\/whats-new-for-c-debugging-in-visual-studio-code\/","title":{"rendered":"What\u2019s new for C++ Debugging in Visual Studio Code"},"content":{"rendered":"

It\u2019s been a minute since our last blog post about C++ in VS Code, but we\u2019ve been working hard on new features and bug fixes! Today, we\u2019re excited to fill you in on the latest and greatest C++ debugger improvements in VS Code, including support for the Apple M1 chip, data breakpoints, and a new run\/debug play button!<\/p>\n

Apple Silicon ARM64 (M1 chip)<\/h2>\n

Last year, we enabled language server support for Apple Silicon ARM64 architecture, which meant you could run the C++ extension\u2019s language server (responsible for things like IntelliSense, code navigation, and autocomplete) natively on the Apple M1 chip. At the time, the C++ extension\u2019s debugger binaries did not run natively on the M1 chip. Now, they do!<\/p>\n

With this latest release<\/a> of the C++ extension, you can seamlessly debug C++ programs when running VS Code on the M1 chip. Give it a try and let us know what you think! If you run into any issues, please follow up on the GitHub tracking issue (#7035)<\/a>.<\/p>\n

Data breakpoints<\/h2>\n

In case you missed it, version 1.8.4 of the C++ extension brought support for data breakpoints (#1410)<\/a> while debugging C++ programs with GDB in VS Code. Data breakpoints break execution when a value stored at a specified memory address changes.<\/p>\n

To set a data breakpoint while debugging in VS Code, right click on a variable in the debug pane and select Break on Value Change<\/strong>.<\/p>\n

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

Immediately, you\u2019ll see the data breakpoint listed in the Breakpoints<\/strong> section of the debug pane.<\/p>\n

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

In this example, if we continue running the program, the next time it breaks will be when local variable i<\/code> changes value. Use the debug control panel to continue running the program.<\/p>\n

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

Sure enough, execution breaks when i<\/code> changes value from 1 to 2.<\/p>\n

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

Troubleshooting data breakpoints<\/h2>\n

In this same example program, if you set a data breakpoint on msg<\/code> of type string, you might see an error message in the Debug Console that says: Unable to set data breakpoint: Value does not fall within the expected range. (Parameter \u2018size\u2019)<\/code>.<\/p>\n

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

This is because the string type is 32 bytes, and there\u2019s a limitation on the size we can set data breakpoints on. This limitation comes from the fact that the architecture that your program runs on has a limited number of hardware data breakpoints it can use. The table below shows how many registers are available to use per architecture.<\/p>\n\n\n\n\n\n\n\n\n\n
DATA BREAKPOINT HARDWARE LIMITATIONS<\/strong><\/td>\n<\/tr>\n
Architecture<\/strong><\/td>\nNumber of hardware supported data breakpoints<\/strong><\/td>\nMax byte size<\/strong><\/td>\n<\/tr>\n<\/thead>\n
x86<\/td>\n4<\/td>\n4<\/td>\n<\/tr>\n
x64<\/td>\n4<\/td>\n8<\/td>\n<\/tr>\n
ARM<\/td>\n1<\/td>\n4<\/td>\n<\/tr>\n
ARM64<\/td>\n2<\/td>\n8<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

<\/h2>\n

Quick run\/debug play button<\/h2>\n

We know that setting up tasks.json and launch.json to run and debug C++ files isn\u2019t always fun. We\u2019re excited to announce that, thanks to this latest release, running and debugging C++ files in VS Code has never been easier!<\/p>\n

With the 1.9.7 update<\/a>, you\u2019ll see a play button in the top right corner of the editor whenever a C or C++ file is active. It\u2019s the same play button used by the Python extension, Java extension, and Code Runner extension.<\/p>\n

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

The play button has two modes: \u201cRun C\/C++ File\u201d and \u201cDebug C\/C++ File.\u201d The default mode is \u201cRun C\/C++ File,\u201d and you can use the drop-down to switch modes.<\/p>\n

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

If you already have a launch.json file in your workspace, the play button will read from it when figuring out how to run and debug your C++ file. If you don\u2019t have launch.json, the play button will create a temporary \u201cquick debug\u201d configuration on the fly, eliminating the need for launch.json altogether!<\/p>\n

We also simplified F5<\/strong> (Run > Start Debugging<\/strong>) to use the same temporary \u201cquick debug\u201d configurations as the play button when your project doesn\u2019t have launch.json. If you need to create launch.json to customize debugging, select Run > Add Configuration… <\/strong>from the main menu.<\/p>\n

Note: <\/strong>We’re still rolling out the run\/debug play button, so you might not see it by default, but you can opt in by enabling C_Cpp: Debug Shortcut<\/strong> in User settings.<\/p>\n

What do you think?<\/h2>\n

Download the C++ extension for Visual Studio Code<\/a>\u202ftoday, give it a try, and let us know what you think. If you run into any issues, or have any suggestions, please report them in the\u202fIssues section of our GitHub repository<\/a>. We can be reached via the comments below or in email at\u202fvisualcpp@microsoft.com<\/a>. You can also find our team on Twitter at\u202f@<\/a>VisualC<\/a>.<\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

It\u2019s been a minute since our last blog post about C++ in VS Code, but we\u2019ve been working hard on new features and bug fixes! Today, we\u2019re excited to fill you in on the latest and greatest C++ debugger improvements in VS Code, including support for the Apple M1 chip, data breakpoints, and a new […]<\/p>\n","protected":false},"author":27203,"featured_media":35994,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-30425","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cplusplus"],"acf":[],"blog_post_summary":"

It\u2019s been a minute since our last blog post about C++ in VS Code, but we\u2019ve been working hard on new features and bug fixes! Today, we\u2019re excited to fill you in on the latest and greatest C++ debugger improvements in VS Code, including support for the Apple M1 chip, data breakpoints, and a new […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/posts\/30425","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/users\/27203"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/comments?post=30425"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/posts\/30425\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/media\/35994"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/media?parent=30425"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/categories?post=30425"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/cppblog\/wp-json\/wp\/v2\/tags?post=30425"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}