Cmake Set Clang: Ensuring Compatibility with Modern CPUs

When developing games on PC, it's essential to ensure compatibility with modern CPUs. In this article, we'll explore how to use Cmake to set the clang compiler and optimize your code for better performance.

One way to achieve this is by safely requiring SSE3 support, which is supported by all Windows 10-compatible CPUs. This can be done by defining the preprocessor symbol XM_NO_XMVECTOR_OVERLOADS before including the DirectXMath headers in Visual C++.

On Clang/LLVM, however, this results in disabling all XMVECTOR C++ overloads and prevents direct element access via `_m128.m128_f32`. Specifically, the `_m128`, `_m128i`, and `_m128d` types are considered opaque types rather than structs, making it impossible to create C++ overloaded functions using those types.

When compiling with clang-cl.exe, you'll need to use specific command-line options. These include `-Wno-c++98-compat`, `-Wno-c++98-compat-pedantic`, and `-Wno-reserved-id-macro`. These options help ensure that your code is compatible with both Clang/LLVM and GNUC.

The C++ Clang Tools for Windows component must be installed to use the ClangCl platform toolset on Gaming.Desktop platforms. If you've already installed Visual Studio, you'll need to repair your Microsoft Game Development Kit (GDK) installation before using Clang/LLVM.

To get started with Clang/LLVM, make sure that your Visual Studio version is 16.11 or later. The required components include C++ Clang Compiler for Windows and C++ Clang-cl for v142 build tools (圆4/x86).

The ClangCL) Platform Toolset uses the Microsoft Standard C++ Library, but other toolsets and runtime combinations may not be compatible. For official support when developing Microsoft Game Development Kit (GDK) titles using Clang/LLVM, use Visual Studio 2019 or 2022 with the clang/LLVM for Windows toolset v12 or later.

By following these guidelines, you can ensure that your code is optimized for modern CPUs and compatible with various platforms. This will help you develop high-performance games that run smoothly on a wide range of devices.

Cmake set clang