If you are building your project with Clang, and find that your code causes undefined behavior not caught by any existing in-compiler test, and you can reproduce it, you might want to ...

- sign up for the developers' list at http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev ,

- skim over http://clang.llvm.org/hacking.html ,

- build from 'trunk' by carefully following a few simple steps in http://clang.llvm.org/get_started.html ,

- wade in and reproduce your bug ,

... and then share your findings.

Together we can build better tools. Anyone with patience and interest can help.

I think we may have our wires crossed. I'm concerned about undefined behavior in my own programs, not undefined behavior in Clang itself. Someone mentioned Clang as a tool that can help detect UB in other programs, but I mentioned that these checks are far from exhaustive.

Sorry, the fault is mine alone. I used an ambiguous description above, now edited.

The only point I wanted to make was that a collective effort might help cut down on ambiguity in expression that the compiler does not identify. I think we could use "more warnings".

He means to say you're welcome to submit patches to make them more exhaustive.