cannot open source file "iostream". Please run the 'Select IntelliSense Configuration...' - #include errors detected. Please update your includePath

[JustinC333]

Environment

• VS Code Version: I have the most recent VSCode (Today is 11/19/24)
• C/C++ Extension Version: v1.22.11

Bug Summary and Steps to Reproduce

This problem popped up out of nowhere in the middle of October.

" cannot open source file "iostream". Please run the 'Select IntelliSense Configuration...' command to locate your system headers.C/C++(1696)"

I'm getting this error in all of my .cpp files.

I am on a MacBook Air btw and I have Clang version 16. The same problem happened on my PC, but I was able to fix that by following the instructions on the VSC website. But nothing seems to work for my Mac. Can some one please help?

I've tried clean uninstalling and reinstalling, changing the compiler path, and the Include path, and I've tried changing the "c_cpp_properties.json" file, but nothing seems to work. I've watched countless youtube videos trying to fix this issue but nothing seemed to work so far. I've spent at least 4+ hours trying to fix this :( .`

(I've included a simple code to show the problem)

(When I type in #include , usually the option for "iostream would pop up but it isn't even showing anymore)

Configuration and Logs

c_cpp_properties: 
{
    "configurations": [
        {
            "name": "Mac",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "defines": [],
            "macFrameworkPath": [
                "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
            ],
            "compilerPath": "/usr/bin/clang",
            "cStandard": "c17",
            "cppStandard": "c++17",
            "intelliSenseMode": "macos-clang-x64"
        }
    ],
    "version": 4
}

Other Extensions

No response

Additional context

No response

[sean-mcmanus]

@JustinC333 What version of the C/C++ extension are you using? 1.22.11 is the latest and 1.23.1 is the latest pre-release.

[JustinC333]

v1.22.11, I just checked @sean-mcmanus

[sean-mcmanus]

@JustinC333 Can you open a .cpp file and run C/C++: Log Diagnostics? The system includes paths should be printed and if you don't see c++ system include paths then it's possible they might not be installed.

It's also possible you may need to run the xcode-select command to switch to the correct system libraries that have C++ installed.

You might also try changing "compilerPath": "/usr/bin/clang", to "compilerPath": "/usr/bin/clang++",.

[JustinC333]

-------- Diagnostics - 11/19/2024, 2:53:52 PM
Version: 1.22.11
Current Configuration:
{
"name": "Mac",
"includePath": [
"/Users/justin.chiang/Documents/VSC/"
],
"defines": [],
"macFrameworkPath": [
"/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
],
"compilerPath": "/usr/bin/clang",
"cStandard": "c17",
"cppStandard": "c++17",
"intelliSenseMode": "macos-clang-x64",
"compilerPathIsExplicit": true,
"cStandardIsExplicit": true,
"cppStandardIsExplicit": true,
"intelliSenseModeIsExplicit": true,
"compilerPathInCppPropertiesJson": "/usr/bin/clang",
"mergeConfigurations": false,
"browse": {
"path": [
"/Users/justin.chiang/Documents/VSC/",
"${workspaceFolder}"
],
"limitSymbolsToIncludedHeaders": true
}
}
Additional Tracked Settings:
{
"editorTabSize": 4,
"editorInsertSpaces": true,
"editorAutoClosingBrackets": "languageDefined",
"filesEncoding": "utf8",
"filesAssociations": {},
"filesExclude": {
"/.git": true,
"/.svn": true,
"/.hg": true,
"/CVS": true,
"/.DS_Store": true,
"/Thumbs.db": true
},
"filesAutoSaveAfterDelay": false,
"editorInlayHintsEnabled": true,
"editorParameterHintsEnabled": true,
"searchExclude": {
"/node_modules": true,
"/bower_components": true,
"**/*.code-search": true
},
"workbenchSettingsEditor": "ui"
}
cpptools version (native): 1.22.11.0
Current database path: /Users/justin.chiang/Library/Caches/vscode-cpptools/b7d6a086ddd06d13e3b74937111de4d8/.browse.VC.db
Translation Unit Mappings:
[ /Users/justin.chiang/Documents/VSC/1. CS10B/1. Labs/Lab 1/main.cpp - source TU]:
Translation Unit Configurations:
[ /Users/justin.chiang/Documents/VSC/1. CS10B/1. Labs/Lab 1/main.cpp ]
Process ID: 12010
Memory Usage: 8 MB
Compiler Path: /usr/bin/clang
Includes:
System Includes:
/usr/local/include
/Library/Developer/CommandLineTools/usr/include/c++/v1
/Library/Developer/CommandLineTools/usr/lib/clang/16/include
/Library/Developer/CommandLineTools/SDKs/MacOSX15.1.sdk/usr/include
/Library/Developer/CommandLineTools/usr/include
Frameworks:
/Library/Developer/CommandLineTools/SDKs/MacOSX15.1.sdk/System/Library/Frameworks
Standard Version: c++17
IntelliSense Mode: macos-clang-arm64
Other Flags:
--clang
--clang_version=170006
Total Memory Usage: 8 MB

------- Workspace parsing diagnostics -------
Number of files discovered (not excluded): 10029

@sean-mcmanus This is what it says when I ran C/C++: Log Diagnostics

[JustinC333]

and I also changed my Compiler path to /usr/bin/clang++ and it did not work

[sean-mcmanus]

@JustinC333 Did you run the C/C++: Select IntelliSense Configuration command from the command palette and select /usr/bin/clang++?

Your log diagnostics system includes seem correct to me.

What happens if you type #include <iostream> and then right-click and do Go to Definition on the iostream? Does a file open?

[JustinC333]

@sean-mcmanus
Sorry for the late message, but when I do the "Go To Definition", it just says "No definition found for iostream".

And yes, I've tried selecting /usr/bin/clang++ from the Configuration but nothing seemed to change

[github-actions]

Hey @sean-mcmanus, this issue might need further attention.

@JustinC333, you can help us out by closing this issue if the problem no longer exists, or adding more information.

[leonbehrndt-parloa]

I am running into the same issue.

[jchinyou]

Sharing here... I don't have the exact root cause of this, but I too had this challenge.

System Info:
Mac OS: Sequoia 15.2
VSCode-Insiders:
Version: 1.97.0-insider Commit: 31188fed068c5c724d73a1956c846401d4d7b01d Date: 2025-01-16T05:07:10.789Z Electron: 32.2.7 ElectronBuildId: 10660205 Chromium: 128.0.6613.186 Node.js: 20.18.1 V8: 12.8.374.38-electron.0 OS: Darwin x64 24.2.0

C/C++: 1.23.3 (Pre-Release)

To resolve this:

Delete Folder: /Library/Developer/CommandLineTools

From the Apple Developer Website (Login Required) Re-Install xCode Command Line Tools, do NOT use xcode-select --install.

VSCode did not pull the include paths automatically, I manually applied them.

To locate the include paths:
From the terminal I ran: clang++ -v -x c++ /dev/null -fsyntax-only

My guess is there is some bug or change, I just don't have the time right now to fully chase it out but hope this unblocks anyone.

[rakhim-ova]

I also had the same issue as above, i tried everything on the internet but finally decided to uninstall Command Line Tools. after reinstalling them, the problem was solved.

[Scissorunner]

I had the same problem after a software update on Mac OS.
Used this guide to uninstall and then reinstall Xcode Command Line Tools.

Uninstall Xcode Command Line Tools: [](url)
Reinstall Xcode Command Line Tools: [](url)

Problem solved.