Msvc Cl

If you're compiling C++ on Windows or porting a GCC-based build to MSVC, this covers the essentials: translating optimization flags, choosing between /MT and /MD runtimes (the main source of LNK2038 errors), and using clang-cl as a drop-in replacement for cl.exe. The flag translation table alone saves you from hunting through MSVC documentation every time you need the equivalent of -O2 or -g. It also walks through vcvars setup, PDB generation, and diagnosing the usual linker mismatches. Honestly, the runtime library section should be required reading for anyone who's ever seen a "mismatch detected for RuntimeLibrary" error and wondered why their third-party library won't link.

skills.sh installs: 671
GitHub stars: 279
last updated: Aug 21, 2026

View on GitHub

Install

$ npx -y skills add mohitmishra786/low-level-dev-skills --skill msvc-cl --agent claude-code

Installs into .claude/skills of the current project.

Files

MSVC cl.exe and clang-cl

Purpose

Guide agents through Windows C/C++ compilation: MSVC cl.exe, clang-cl as MSVC-compatible driver, MSBuild project settings, and runtime library choices.

Triggers

"How do I compile with MSVC from the command line?"
"What is the MSVC equivalent of -O2?"
"/MT vs /MD — which do I use?"
"How do I use clang-cl instead of cl.exe?"
"I'm getting LNK errors on Windows"
"How do I generate PDB files?"

Workflow

1. Set up the environment

MSVC requires the Visual Studio environment variables. Use the Developer Command Prompt or set up manually:

REM x64 native
"C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Auxiliary\Build\vcvars64.bat"

REM x86 cross (host x64, target x86)
"...\vcvarsamd64_x86.bat"

REM Check compiler version
cl /?

In CMake, use the "Visual Studio 17 2022" generator or pass -DCMAKE_GENERATOR="Visual Studio 17 2022".