Error Squiggles inside Template in C++

[srivishalv18]

Environment

• OS and Version: macOS Sonoma
• VS Code Version: 1.78.0
• C/C++ Extension Version: Latest (1.19.7)
• If using SSH remote, specify OS of remote machine: -

Bug Summary and Steps to Reproduce

Bug Summary:
The Error Squiggles will not show up inside a template inside a class. I have attached screen shots of what happens when I have the template line, and when its commented out.

Steps to reproduce:

1. Make a new header file
2. have a basic header like include iostream
3. Make a template : template
4. Make a class
5. Error Lines will not show up in the class inside template.
6. See error

Expected behavior:

Error Squiggles inside template.
Without Template:

With Template:

Configuration and Logs

{
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${default}"
            ],
            "defines": [],
            "compilerPath": "/usr/bin/g++",
            "cStandard": "c17",
            "cppStandard": "c++20",
            "intelliSenseMode": "${default}"
        },
        {
            "name": "Mac",
            "includePath": [
                "${default}",
                "/opt/homebrew/Cellar/googletest/1.14.0/include"
            ],
            "defines": [],
            "compilerPath": "/usr/bin/g++",
            "cStandard": "c17",
            "cppStandard": "c++20",
            "intelliSenseMode": "${default}"
        }
    ],
    "version": 4
}

-------- Diagnostics - 3/13/2024, 1:36:03 AM
Version: 1.19.7
Current Configuration:
{
    "name": "Mac",
    "includePath": [
        "/opt/homebrew/Cellar/googletest/1.14.0/include"
    ],
    "defines": [],
    "macFrameworkPath": [
        "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks"
    ],
    "cStandard": "c17",
    "cppStandard": "c++17",
    "intelliSenseMode": "macos-clang-arm64",
    "compilerPathIsExplicit": true,
    "cStandardIsExplicit": true,
    "cppStandardIsExplicit": true,
    "intelliSenseModeIsExplicit": true,
    "mergeConfigurations": false,
    "compilerPath": "/usr/bin/clang",
    "browse": {
        "path": [
            "/opt/homebrew/Cellar/googletest/1.14.0/include",
            "${workspaceFolder}"
        ],
        "limitSymbolsToIncludedHeaders": true
    }
}
cpptools version (native): 1.19.7.0
Translation Unit Mappings:
[ /Users/srivishal/Documents/Data Structs/Projects/ProjectX/Starter Code/prqueue_main.cpp - source TU]:
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/c++/v1/__iterator/prev.h
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/c++/v1/__utility/pair.h
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/c++/v1/atomic
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/stdio.h
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/stdlib.h
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/sys/_types/_in_addr_t.h
    /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/sys/wait.h
    /Users/srivishal/Documents/Data Structs/Projects/ProjectX/Starter Code/prqueue.h
[ /Users/srivishal/Documents/Data Structs/Projects/ProjectX/Starter Code/temp.h - source TU]:
Translation Unit Configurations:
[ /Users/srivishal/Documents/Data Structs/Projects/ProjectX/Starter Code/prqueue_main.cpp ]:
    Process ID: 34509
    Memory Usage: 7 MB
    Compiler Path: /usr/bin/clang
    Includes:
        /opt/homebrew/Cellar/googletest/1.14.0/include
        /usr/local/include
        /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/c++/v1
        /Library/Developer/CommandLineTools/usr/lib/clang/15.0.0/include
        /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include
        /Library/Developer/CommandLineTools/usr/include
    Frameworks:
        /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/System/Library/Frameworks
    Standard Version: c++17
    IntelliSense Mode: macos-clang-arm64
    Other Flags:
        --clang
        --clang_version=160000
[ /Users/srivishal/Documents/Data Structs/Projects/ProjectX/Starter Code/temp.h ]:
    Process ID: 34553
    Memory Usage: 77 MB
    Compiler Path: /usr/bin/clang
    Includes:
        /opt/homebrew/Cellar/googletest/1.14.0/include
        /usr/local/include
        /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include/c++/v1
        /Library/Developer/CommandLineTools/usr/lib/clang/15.0.0/include
        /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/usr/include
        /Library/Developer/CommandLineTools/usr/include
    Frameworks:
        /Library/Developer/CommandLineTools/SDKs/MacOSX14.2.sdk/System/Library/Frameworks
    Standard Version: c++17
    IntelliSense Mode: macos-clang-arm64
    Other Flags:
        --clang
        --clang_version=160000
Total Memory Usage: 84 MB

------- Workspace parsing diagnostics -------
Number of files discovered (not excluded): 11500

Other Extensions

Additional context

I'm sorry if this is not a bug, I've been trying to start on my project which is due Friday but the error squiggles don't work. The error squiggles help me out a lot and I don't think I can code without them so please let me know if anything is wrong !

Code from my project where I discovered the bug:
Take a look at parent, it should give me an error, but it doesn't.

It does when I comment the template out though.

[sean-mcmanus]

We're already tracking this with #1946 and #2973 , so you can upvote those.