I have a very simple program that I am attempting to run with vs code using the c++ extension with clang++ on mac m1 chip.

I’ve done a decently exhaustive search on this issue, and haven’t figured out the root cause. This seems to be a common early mistake to new c++ users, so any solution I will try my best to communicate along. Here are my files.

add.hpp:

int add(int x, int y);

main.cpp:

#include "add.hpp"
#include <iostream>

int main()
{
    std::cout << "The sum of 3 and 4 is " << add(3, 4) << 'n';
    return 0;
}

task.json:

{
    "tasks": [
        {
            "type": "cppbuild",
            "label": "C/C++: clang++ build active file",
            "command": "/usr/bin/clang++",
            "args": [
                "-fcolor-diagnostics",
                "-fansi-escape-codes",
                "-g",
                "-O2",
                "-DNDEBUG",
                "-ggdb",
                "-pedantic-errors",
                "-Wall",
                "-Weffc++",
                "-Wextra",
                "-Wconversion",
                "-Wsign-conversion",
                "-std=c++17",
                "${fileDirname}/**.cpp",
                "-o",
                "${fileDirname}/${fileBasenameNoExtension}"
            ],
            "options": {
                "cwd": "${fileDirname}"
            },
            "problemMatcher": [
                "$gcc"
            ],
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "detail": "Task generated by Debugger."
        }
    ],
    "version": "2.0.0"
}

I receive the following error:

Starting build...
/usr/bin/clang++ -fcolor-diagnostics -fansi-escape-codes -g -O2 -DNDEBUG -ggdb -pedantic-errors -Wall -Weffc++ -Wextra -Wconversion -Wsign-conversion -std=c++17 /Users/kendallreid/cpp_bug/**.cpp -o /Users/kendallreid/cpp_bug/main
Undefined symbols for architecture arm64:
  "add(int, int)", referenced from:
      _main in main-11e098.o
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Build finished with error(s).