Compiler Explorer

Compiler Explorer is an interactive compiler exploration website. Edit code in C, C++, C#, F#, Rust, Go, D, Haskell, Swift, Pascal, ispc, Python, Java or in any of the other 30+ supported languages, and see how that code looks after being compiled in real time. Multiple compilers are supported for each language, many different tools and visualisations are available, and the UI layout is configurable.

Using Compiler Explorer

Assuming you have a compatible version of node installed, on Linux simply running make ought to get you up and running with an Explorer running on port 10240 on your local machine: http://localhost:10240/. Currently, Compiler Explorer requires node 16 (LTS version) installed, either on the path or at NODE_DIR (an environment variable or make parameter), and will soon be moving to v18.

Running with make EXTRA_ARGS='--language LANG' will allow you to load hermes exclusively. If you want to use other languages locally, you may run make without any arguments.

For development, we suggest using make dev to enable some useful features, such as automatic reloading on file changes and shorter startup times. You can also use npm run dev to run if make dev doesn't work on your machine.

Using Hermes

Compiler Explorer will look for a hermes executable on your system $PATH. This means you must add the build directory for hermes to your path. In the case of a CMake build, it could be something like this in your .zshrc:

# add release hermes to the path
export PATH=$PATH:~/builds/release/bin

A typical use-case for using compiler explorer is to A/B a local version of the hermes compiler against main. To support this workflow, compiler explorer will also try to look for an executable hermes-base. It's easiest to just rename the hermes executable produced during a typical build to hermes-base. Then both hermes and hermes-base will be side-by-side in the same build directory, and you can point the $PATH there.

Sample CMake workflow

Setup

• git clone https://github.com/fbmal7/hbc-explorer.git
• cd hbc-explorer
• make EXTRA_ARGS='--language hermes' - note this will also start the server.

Running

• Start from a checkout of a stable commit
• cd ~/builds/release
• ninja && cp bin/hermes bin/hermes-base
• Checkout your experimental diff
• Rebuild hermes, ninja
• Run npm run dev
• Select Templates --> Diff Two Compilers

Note that every time you rebuild Hermes you must re-run npm run dev in order to load in the new executable.