Improper formatting of intellisense text for C function 'free'

[RushilJalal]

Environment

• OS and Version: Windows 11
• VS Code Version: 1.106.3(user setup)
• C/C++ Extension Version: 1.29.2
• If using SSH remote, specify OS of remote machine: Ubuntu WSL2 24.04.3 LTS

Bug Summary and Steps to Reproduce

Bug Summary:

Steps to reproduce:

1. Create a C file. Ensure you have the C/C++ extension.
2. Add this code

#include <stdlib.h>

int main(){
  free();
}

3. Hover over the function free
4. Notice the formatting issue.

Expected behavior:
Normal formatting of text

Configuration and Logs

{
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${workspaceFolder}/**"
            ],
            "defines": [],
            "compilerPath": "/usr/bin/gcc",
            "cStandard": "c17",
            "cppStandard": "gnu++17",
            "intelliSenseMode": "linux-gcc-x64"
        }
    ],
    "version": 4
}

-------- Diagnostics - 12/9/2025, 8:25:23 AM
Version: 1.29.2
Current Configuration:
{
    "name": "Linux",
    "includePath": [
        "/home/rushil/code/text-editor/**"
    ],
    "defines": [],
    "compilerPath": "/usr/bin/gcc",
    "cStandard": "c17",
    "cppStandard": "gnu++17",
    "intelliSenseMode": "linux-gcc-x64",
    "compilerPathInCppPropertiesJson": "/usr/bin/gcc",
    "intelliSenseModeIsExplicit": false,
    "cStandardIsExplicit": false,
    "cppStandardIsExplicit": false,
    "mergeConfigurations": false,
    "recursiveIncludes": {},
    "recursiveIncludesReduceIsExplicit": false,
    "recursiveIncludesPriorityIsExplicit": false,
    "recursiveIncludesOrderIsExplicit": false,
    "compilerPathIsExplicit": false,
    "browse": {
        "limitSymbolsToIncludedHeaders": true
    }
}
Additional Tracked Settings:
{
    "editorTabSize": 4,
    "editorInsertSpaces": true,
    "editorAutoClosingBrackets": "languageDefined",
    "filesEncoding": "utf8",
    "filesAssociations": {
        "*.css": "css",
        "*.ejs": "html",
        "termios.h": "c"
    },
    "filesExclude": {
        "**/.git": true,
        "**/.svn": true,
        "**/.hg": true,
        "**/.DS_Store": true,
        "**/Thumbs.db": true
    },
    "filesAutoSaveAfterDelay": true,
    "editorInlayHintsEnabled": true,
    "editorParameterHintsEnabled": true,
    "searchExclude": {
        "**/node_modules": true,
        "**/bower_components": true,
        "**/*.code-search": true
    },
    "workbenchSettingsEditor": "ui"
}
cpptools version (native): 1.29.2.0
Current database path: /home/rushil/.cache/vscode-cpptools/d4408fc46f5f5febc3c5553de1ef4ec5/.browse.VC.db
Translation Unit Mappings:
[ /home/rushil/code/text-editor/main.c - source TU]:
    /usr/include/stdlib.h
Translation Unit Configurations:
[ /home/rushil/code/text-editor/main.c ]
    Process ID: 100373
    Memory Usage: 24 MB
    Compiler Path: /usr/bin/gcc
    Include paths:
        system include: /usr/lib/gcc/x86_64-linux-gnu/13/include
        system include: /usr/local/include
        system include: /usr/include/x86_64-linux-gnu
        system include: /usr/include
    Standard Version: c17
    IntelliSense Mode: linux-gcc-x64
    Other Flags:
        --gcc
        --gnu_version=130300
Total Memory Usage: 24 MB

------- Workspace parsing diagnostics -------
Number of files discovered (not excluded): 2998
Number of files parsed: 258

Other Extensions

No response

Additional context

I would like to work on this issue, if possible.

[sean-mcmanus]

@RushilJalal The fix would probably in in our closed source cpptools process.

The problem is that gcc is using

`quick_exit'

and the backtick is currently treated as markdown, so we'd have to add a special case for a backtick followed by a normal '.