Cheerp - a C/C++ compiler for Web applications

Cheerp is an open-source, commercial C/C++ compiler for Web applications. It allows to compile virtually any C/C++ code (up to C++14) to WebAssembly, JavaScript, asm.js or a combination thereof.

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Main documentation link: https://github.com/leaningtech/cheerp-meta/wiki

Main project link: https://leaningtech.com/pages/cheerp.html

This repository is the main reference for documentation, issue tracking, and release notes.

What is Cheerp

Cheerp is a C/C++ compiler for the Web, based and integrated into the LLVM/clang infrastructure, and featuring numerous custom optimisation steps to maximise performance and minimise size of the compiled JavaScript/WebAssembly output. As such, Cheerp is the best performing, most optimised C++ to WebAssembly compiler available on the market

Cheerp is used mainly to port existing C/C++ libraries and applications to HTML5, but can also be used to write high-performance Web applications and components from scratch. C/C++ gets optimised and compiled into JavaScript/WebAssembly, and can easily be deployed as part of a web page.

What is unique about Cheerp?

Cheerp enables C/C++ code to be compiled to WebAssembly, JavaScript, asm.js or a combination thereof. Compared to alternative C/C++ compilers for web applications such as Emscripten, Cheerp:

Generates 6% faster (on average) WebAssembly code, but can also compile to a JavaScript output with dynamic memory (garbage-collectible output), zero-overhead DOM manipulation and access to WebApis and superior C++-JavaScript interoperability.
Allows to compile a single code base into a combination of WebAssembly and JavaScript by (optionally) tagging portions of the code with [[cheerp::genericjs]] and [[cheerp::wasm]].
Can generate code on average 11% smaller than Emscripten (8% post compression).

Cheerp is open-source software and is free to use for GPLv2 projects. Non-copyleft commercial licenses, commercial support and consulting packages are available from Leaning Technologies.

Get started

First time user? We recommend following the Getting started page, that will guide though this steps:

Or look at the sidebar to find lots of useful materials

Bugs and Questions

You can get in touch with us using our Gitter chat, or by filing a bug on our Issue tracker.

Documentation