Compiler Explorer is an interactive compiler. The left-hand pane shows editable C, C++, Rust, Go, D, Haskell, Swift, Pascal (and some more!) code. The right, the assembly output of having compiled the code with a given compiler and settings. Multiple compilers are supported, and the UI layout is configurable (thanks to GoldenLayout). There is also an ispc compiler ? for a C variant with extensions for SPMD.
Try out at godbolt.org
You can support this project on Patreon.
Compiler Explorer follows a Code of Conduct which aims to foster an open and welcoming environment.
Compiler Explorer was started in 2012 to serve my needs at my previous employer to show how
C++ constructs translated to assembly code. It started out as a
tmux session with
vi running in one
watch gcc -S foo.cc -o - running in the other.
Since then, it has become a public website serving around 210,000 compilations per day.
There is now a FAQ section in the repository wiki. If your question is not present, please contact us as described below so we can help you. If you find that the FAQ is lacking some important point, please free to contribute to it and/or ask us to clarify it.
There are a number of videos that showcase some of the features of Compiler Explorer: A presentation for CppCon 2019 about the project https://www.youtube.com/watch?v=kIoZDUd5DKw and an older 2 part series of videos which go into a bit more detail into the more obscure features https://www.youtube.com/watch?v=4_HL3PH4wDg
If you are interested in developing, or want to see the discussions between
existing developers, feel free to join the cpplang
the development mailing list
Compiler Explorer is written in Node.js.
Assuming you have a compatible version of
node installed, 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 the latest LTS
(v12) installed, either on the path or at
(an environment variable or
make EXTRA_ARGS='--language LANG' will allow you to load
LANG exclusively, where
LANG is one for the language ids/aliases defined
Makefile will automatically install all the
third party libraries needed to run; using
npm to install server-side and
client side components.
Some languages need extra tools to demangle them, e.g.
Such tools are kept separately in the
A Road map is available which gives a little insight into the future plans for Compiler Explorer.
Running a local instance
If you want to point it at your own GCC or similar binaries, either edit the
etc/config/LANG.defaults.properties or else make a new one with
LANG as needed.
*.local.properties files have the highest priority when loading properties.
When running in a corporate setting the URL shortening service can be replaced
by an internal one if the default storage driver isn't appropriate for your
environment. To do this, add a new module in
urlShortenService variable in configuration. This module should
export a single function, see the tinyurl module
for an example.
There's a simple restful API that can be used to do compiles to asm and to list compilers.
You can find the API documentation here.
Compiler Explorer is maintained by the awesome people listed in the AUTHORS file.
We would like to thank the contributors listed in the CONTRIBUTORS file, who have helped shape Compiler Explorer.
We would also like to specially thank these people for their contributions to Compiler Explorer:
- Gabriel Devillers (while working for Kalray)
- Johan Engelen
- Joshua Sheard
- Marc Poulhiès
- Andrew Pardoe
We would like to thank JetBrains for their support and for donating licenses to their excellent products to develop Compiler Explorer.