[cliffbean]

The link he cited still does apply. It discusses several different issues. PNaCl's portability only covers a subset of them.

[BrendanEich]

Thanks! I happen to agree with with Dan Gohman (http://comments.gmane.org/gmane.comp.compilers.llvm.devel/43...), but I'm not sure where Chris Lattner ended up on this.

Much is possible in software, so perhaps some day, or under some transformation, LLVM bitcode would be suitable as a stable long-term object file format.

There's still a point here: PNaCl is pushing a stone up a very tall hill. ANDF and other Universal Object formats go back to the 70s if not earlier. It's very difficult to standardize such things, never mind Pepper.

[gsnedders]

FWIW, the aim for LLVM is to avoid breaking the bitcode format now 3.0 has shipped — not that it's platform independent or anything else yet.