1349479 - stylo: bindgen busted on llvm4.0

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect, P1)

Description

[Chih-Hsuan Kuo [:tommykuo]]

I built stylo and failed with the following messages.

--- Error Message ---
 1:12.41 error: failed to run custom build command for `style v0.0.1 (file:///Users/kuoe0/Works/Mozilla/gecko-dev/servo/components/style)`
 1:12.42 process didn't exit successfully: `/Users/kuoe0/Works/Mozilla/obj-central-default-darwin-desktop-stylo-debug/toolkit/library/debug/build/style-b3825590b01f853f/build-script-build` (exit code: 101)
 ...
 ...
 1:16.61
 1:16.61 --- stderr
 1:16.61 thread '<unnamed>' panicked at 'C'mon: Continue', /Users/rustbuild/src/rust-buildbot/slave/stable-dist-rustc-mac/build/src/libcore/result.rs:868
 1:16.61 note: Run with `RUST_BACKTRACE=1` for a backtrace.
 1:16.61 thread '<unnamed>' panicked at 'C'mon: Continue', /Users/rustbuild/src/rust-buildbot/slave/stable-dist-rustc-mac/build/src/libcore/result.rs:868
 1:16.61 thread '<unnamed>' panicked at 'C'mon: Continue', /Users/rustbuild/src/rust-buildbot/slave/stable-dist-rustc-mac/build/src/libcore/result.rs:868
 1:16.61 thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Any', /Users/rustbuild/src/rust-buildbot/slave/stable-dist-rustc-mac/build/src/libcore/result.rs:868


--- System Env ---

OS: macOS 10.12
Rust: rustc 1.16.0 (30cf806ef 2017-03-10)
LLVM: 4.0.0


--- Mozconfig ---

export LLVM_CONFIG="/usr/local/opt/llvm/bin/llvm-config"
export LDFLAGS=-Wl,-no_compact_unwind

export CC="/usr/local/bin/ccache clang"
export CXX="/usr/local/bin/ccache clang++"

ac_add_options --with-ccache
ac_add_options --enable-stylo
ac_add_options --enable-debug

Comment 1

[Chih-Hsuan Kuo [:tommykuo]]

Hi Emilio, do you know how to make it compile? Thanks!

Comment 2

[Emilio Cobos Álvarez (:emilio)]

Which version of clang are you using? We're tracking down a few issues with bindgen and newer libclang at https://github.com/servo/rust-bindgen/issues/584.

Meanwhile you can probably build with --disable-stylo-build-bindgen (http://searchfox.org/mozilla-central/rev/0079c7adf3b329bff579d3bbe6ac7ba2f6218a19/toolkit/moz.configure#580)

Comment 3

[Chih-Hsuan Kuo [:tommykuo]]

My clang version is 4.0.0. I think this bug is as same as that issue.

Comment 4

[Xidorn Quan [:xidorn] UTC+10]

I suggest this to be at least P3 (and probably P2) since it stops people from using newer version of llvm (I tried and got blocked for a day and eventually downgraded my llvm install to 3.9 to work around), and actually we need bindgen to get fixed soonish for other bustage as well.

Comment 5

[Bobby Holley (:bholley)]

Ok, looks like you have a patch for it over in https://github.com/servo/rust-bindgen/pull/594

Comment 6

[Xidorn Quan [:xidorn] UTC+10]

I'm not actively working on this... That patch itself doesn't fix all problems. The main issue is that bindgen master doesn't work properly at all with stylo even with older llvm, which is the actual blocker. We need to wait for that to be solved before we can confidently try to fix it with llvm 4.0.

Comment 7

[Bobby Holley (:bholley)]

Ok. Do we have somebody on point for fixing the bindgen regression? fitzgen?

Comment 8

[Nick Fitzgerald [:fitzgen] [⏰PST; UTC-8]]

I've been in work weeks for the last week and a half and through the end of this week, so I haven't had time to do any hacking (and won't again until next week). However, this is a blocker for me landing my SM rust bindings stuff, so I'll definitely get to it eventually.

Anyone else should feel free to steal the work from me if you urgently need a fix.

Comment 9

[Bobby Holley (:bholley)]

Ok, I'll mark this as assigned to fitzgen, and we can steal it if somebody needs it sooner.

Comment 10

[Simon Sapin (:SimonSapin)]

On OS X (where "brew install llvm" now gives 4.0.0) I’ve worked around this by running "brew install llvm@3.9" and changing .mozconfig to:

export LLVM_CONFIG="/usr/local/opt/llvm@3.9/bin/llvm-config"

Comment 11

[Chih-Hsuan Kuo [:tommykuo]]

(In reply to Simon Sapin (:SimonSapin) from comment #10)
> On OS X (where "brew install llvm" now gives 4.0.0) I’ve worked around this
> by running "brew install llvm@3.9" and changing .mozconfig to:
> 
> export LLVM_CONFIG="/usr/local/opt/llvm@3.9/bin/llvm-config"

I have tried this work around last week, and it still failed. There are some settings in my mozconfig and it works.

```
export PATH="/usr/local/opt/llvm@3.9/bin:$PATH"
export CPPFLAGS="-I/usr/local/opt/llvm@3.9/include"
export LDFLAGS="-L/usr/local/opt/llvm@3.9/lib -Wl,-no_compact_unwind,-rpath,/usr/local/opt/llvm@3.9/lib"
```

Comment 12

[Nick Fitzgerald [:fitzgen] [⏰PST; UTC-8]]

Stylo bindings are now working again on master bindgen with libclang 3.9.

Unfortunately, there is a regression in libclang >= 4 surrounding default template type parameters, which I suspect Stylo bindings hit but I'm not 100% sure as I haven't explicitly rebuilt libclang 4 and tested again.

Emilio is working on upstreaming a fix, but I don't know if Clang will uplift it to the 4.X series or if we jsut have to say either use 3.9 or tip.

https://bugs.llvm.org/show_bug.cgi?id=32539
https://reviews.llvm.org/D31732
https://github.com/servo/rust-bindgen/issues/585

Reassigning this bug to Emilio since he is already working on the upstream fix, and there isn't anything else left AFAIK.

Comment 14

[Jan Beich]

--enable-stylo on mozilla-central with below patch seems to build fine with LLVM 4.0.1rc1 for me. Are we waiting for something more?

https://github.com/jbeich/gecko-dev/commit/4e3da5030b45

Comment 15

[Emilio Cobos Álvarez (:emilio)]

Nope!, the recent bindgen update should've fixed both llvm 4.0 and 5.0. Thanks for checking!