Error building rust with -g

[Manishearth]

rustc: /home/rustbuild/src/rust-buildbot/slave/snap3-linux/build/src/llvm/lib/IR/DebugInfo.cpp:159: uint64_t llvm::DIVariable::getPieceOffset() const: Assertion `isVariablePiece()' failed.
Aborted (core dumped)
make: *** [x86_64-unknown-linux-gnu/stage0/lib/rustlib/x86_64-unknown-linux-gnu/lib/stamp.rustc_typeck] Error 134

(I was running RUSTFLAGS="-g" CFG_RUSTC_FLAGS="-g" make -j4, since I forgot which flag works)

I get the same error even after a make clean.

[huonw]

cc @michaelwoerister

[michaelwoerister]

Seems to be something related to the recent LLVM updates. It's on my radar.

[michaelwoerister]

Update: It's likely that this particular assertion failure has been resolved by the recent LLVM update. However, I'm hitting a new error now, which seems to be a regression of #17201. I'm looking into it right now.

[michaelwoerister]

👏 Alright! 👍
With a quick and dirty fix assigning debug locations to lang-time call instructions the regression is gone and isVariablePiece() assertion too. It'll take some time to implement a clean fix but then this issue should be solved.

[steveklabnik]

🎊