This one surprised me:
"Get Clang going again - what do we need to do to get it going?"
So, as of a few months ago, after long discussion, the decision as I understood it was to make us GNU11, not C11. I went back and reviewed the discussion, and that was how it seemed to come out.
Disclaimer: I help lead a kernel project (Harvey) which builds a working kernel under 3 versions of clang and 3 versions of gcc. It's not easy but it's not rocket science to make it go. We've derived a lot of benefit from making that work; each compiler finds errors the others miss. Tannenbaum is a strong advocate for confirming to C11, and compiling under many compilers, not, as he calls it, "GCC version of C".
I would be a lot happier were we decide to stop using GNU features in our codebase, but IIUC, we've made an explicit decision to continuing doing so. Given that, how does Clang fit in to our future?
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