Contributing to clang

Hi all,

I’ve been looking to get involved with clang for a while now. I’ve started looking at the open projects page and was looking for some advice.

Clang is something I am really interested in but realize there is a lot of getting up to speed, can anyone recommend an area where help is needed that might help me get my feet wet. I would really like to get involved, even if it takes me a long time to produce anything valuable.


The way I started in clang was to look for easy diagnostic bugs (false
positives, false negatives, perhaps miswordings, etc) - I could just
do a side-by-side debugging session with a true positive and a false
negative and see where the two steps diverged - where did we make the
wrong choice/do something different, and go from there.

Chances are patches like that will go through some iteration as you
won't necessarily know the /right/ place to make the fix, just /a/
place that seems to fix the bug, but it's something to start.

Cleanup patches are also a pretty good place to start - I've been
doing lots of std::unique_ptr migration (from raw owning pointers to
std::unique_ptr/llvm::make_unique, etc) when I get bored & am happy to
review similar changes. Some of the memory ownership semantics are
weird/difficult - feel free to steer clear of those and try to find
some low hanging fruit. In many cases I've found APIs that just go
into the raw pointer domain to bridge a function call (caller uses
unique_ptr and calls release() to pass to the callee, that immediately
rebinds to a unique_ptr) - changing the parameter type to unique_ptr
so it's explicit in the API is great low-friction improvement.

- David

Grep the bug list,, and see if anything peeks your interest.
You might also consider subscribing to the mailing list


I’d just like to add that Clang has many different parts, parser + semantic analysis, C api, static analyzer, IR generation, ast matchers, tools like clang-format and clang-modernize. My suggestion would be to find a bug from the list that you know how to reproduce and think you understand and try to fix it. You can hunt for FIXMEs in the code but these often assume familiarity with surrounding code.

That’s a great idea guys. Start by trying to reproduce and fix some bugs.

I was browsing through the list, I assume I should look at the ones that are unassigned right?

If a bug has been assigned and you're interested, I suggest contacting the
assignee. They might be happy to offload the work and assist you with the


Thanks Chad.

Thanks again for the suggestions everyone, I’m excited to pick a bug or two and start hacking on clang.

We all hangout on the IRC channel, so feel free to jump on there as well.


Thanks Chad, will be getting involved soon and will be on the channel.


Thanks Chad, will be getting involved soon and will be on the channel.