Setting up a GTest Hello World Project on Windows with MSYS2, MinGW-w64, and vcpkg

Welcome to my updated demo of a Google Test “Hello, World!” project on Windows using MSYS2, MinGW-w64, and vcpkg. In this guide, we’ll walk through:

1. Adjusting environment variable priority in Windows so the correct g++ is picked up.
2. Installing and configuring MSYS2, MinGW-w64, and vcpkg.
3. Dealing with common issues such as “Unable to find a valid Visual Studio instance” and how to ensure we’re using the x64-mingw-dynamic triplet.
4. Building and running a minimal Google Test example.

1. Prioritize the Correct Compiler in Windows

When you have multiple versions of g++ on your system (from MSYS2, Cygwin, or elsewhere), it’s important that MSYS2’s MinGW-w64 compiler is picked up first. You can check which ones are visible in PATH by opening Command Prompt (not MSYS2) and running:

C:\Users\Gordon> where g++

If you see multiple paths, reorder your Windows environment variables so that:

C:\msys64\mingw64\bin

appears before any others in the PATH. This ensures that when you run g++, Windows uses the MinGW-w64 version first.

1. Open “System Properties” → “Advanced” → “Environment Variables.”
2. Edit the Path variable and move C:\msys64\mingw64\bin to the top.
3. Apply changes and restart any open terminals so the updated PATH is recognized.

2. Installing MSYS2 and MinGW-w64

1. Install MSYS2
   Download MSYS2 and run through the official installer.

2. Open MSYS2 and update packages with:

   pacman -Syuu
   

   (Follow on-screen prompts, then reopen MSYS2 if necessary.)

3. Install Required Tools (in MSYS2 MingW64 shell):

   pacman -S --needed git base-devel mingw-w64-x86_64-toolchain \
     mingw-w64-x86_64-clang mingw-w64-x86_64-cmake
   

4. Create a Symlink for make
   By default, MinGW’s make is named mingw32-make.exe. To ease usage:

   cd /mingw64/bin
   ln -s mingw32-make.exe make.exe
   

3. Bootstrapping vcpkg in MSYS2

3.1 Clone vcpkg

In the MingW64 terminal:

cd /mingw64/bin
git clone https://github.com/microsoft/vcpkg.git
cd vcpkg

3.2 Run the Bootstrap Script

./bootstrap-vcpkg.bat

4. Common Installation Pitfall

If you try installing GTest before specifying your triplet, you may see:

error: in triplet x64-windows: Unable to find a valid Visual Studio instance
Could not locate a complete Visual Studio instance

This happens because vcpkg defaults to the x64-windows triplet, expecting Visual Studio.

5. Setting the Correct Triplet

To use MinGW-w64, export these environment variables first:

export VCPKG_DEFAULT_TRIPLET=x64-mingw-dynamic
export VCPKG_DEFAULT_HOST_TRIPLET=x64-mingw-dynamic

Then install GTest again:

./vcpkg install gtest

6. Integrate vcpkg (Optional)

Run:

./vcpkg integrate install

This instructs you to use:

-DCMAKE_TOOLCHAIN_FILE=C:/msys64/mingw64/bin/vcpkg/scripts/buildsystems/vcpkg.cmake

in your CMake commands.

7. Verifying Installed Packages

Check what’s installed with:

./vcpkg list

You should see gtest:x64-mingw-dynamic listed.

8. Creating a Minimal GTest Project

Here’s a simple folder structure for a “Hello, World!” project:

gtest_MinGW64_vscode_win_helloworld/
├── CMakeLists.txt
├── src/
│   └── main.cpp
└── tests/
    └── test_helloworld.cpp

CMakeLists.txt

cmake_minimum_required(VERSION 3.10)
project(GTestHelloWorld CXX)

# Option A: Hard-code the vcpkg toolchain file here
#set(CMAKE_TOOLCHAIN_FILE "C:/msys64/mingw64/bin/vcpkg/scripts/buildsystems/vcpkg.cmake" CACHE STRING "" FORCE)

# Option B: Omit the line above and specify via command line

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED True)

add_executable(helloworld src/main.cpp)

find_package(GTest CONFIG REQUIRED)

add_executable(tests tests/test_helloworld.cpp)
target_link_libraries(tests PRIVATE GTest::gtest GTest::gtest_main)

enable_testing()
add_test(NAME MyHelloWorldTest COMMAND tests)

src/main.cpp

#include <iostream>

int main() {
    std::cout << "Hello, World!" << std::endl;
    return 0;
}

tests/test_helloworld.cpp

#include <gtest/gtest.h>

// Sample function to test
int add(int a, int b) {
    return a + b;
}

TEST(HelloWorldTest, TestAdd) {
    EXPECT_EQ(add(2, 2), 4);
    EXPECT_EQ(add(-1, 1), 0);
}

TEST(HelloWorldTest, AnotherTest) {
    EXPECT_TRUE(true);
}

9. Building and Running Tests

1. Create a build directory and go inside it:

   cd gtest_MinGW64_vscode_win_helloworld
   mkdir build && cd build
   

2. Invoke CMake using the MinGW Makefiles generator and the vcpkg toolchain:

   cmake -G "MinGW Makefiles" \
     -DCMAKE_TOOLCHAIN_FILE=C:/msys64/mingw64/bin/vcpkg/scripts/buildsystems/vcpkg.cmake \
     -DVCPKG_TARGET_TRIPLET=x64-mingw-dynamic \
     ..
   

3. Build the project:

   cmake --build .
   

   This produces helloworld.exe and tests.exe.

4. Run the tests:

   ./tests
   

   You should see Google Test’s output indicating 2 passing tests.

Conclusion

By prioritizing the correct g++ in your Windows PATH and setting the x64-mingw-dynamic triplet, you can avoid the Visual Studio dependency and run GTest projects with MSYS2 + MinGW-w64. The vcpkg package manager simplifies installing libraries like GTest, and you’re free to expand this skeleton into a more advanced project.

If you have any questions or run into issues, feel free to reach out. Happy coding!