Fix rust-lldb wrapper scripts.

[golddranks]

Currently the rust-lldb wrapper provided by Rust project is broken. The error messages it produces on launch are as follows:

warning: ignoring unknown option: --one-line-before-file=command script import "/Users/kon/.rustup/toolchains/nightly-2019-05-02-x86_64-apple-darwin/lib/rustlib/etc/lldb_rust_formatters.py"
warning: ignoring unknown option: --one-line-before-file=type summary add --no-value --python-function lldb_rust_formatters.print_val -x ".*" --category Rust
warning: ignoring unknown option: --one-line-before-file=type category enable Rust
(lldb) target create "target/debug/nagare"
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/Users/kon/.rustup/toolchains/nightly-2019-05-02-x86_64-apple-darwin/lib/rustlib/x86_64-apple-darwin/lib/python2.7/site-packages/lldb/__init__.py", line 1481, in <module>
class SBAddress(object):
File "/Users/kon/.rustup/toolchains/nightly-2019-05-02-x86_64-apple-darwin/lib/rustlib/x86_64-apple-darwin/lib/python2.7/site-packages/lldb/__init__.py", line 1647, in SBAddress
__swig_getmethods__["module"] = GetModule
NameError: name '__swig_getmethods__' is not defined
Traceback (most recent call last):
File "<string>", line 1, in <module>
NameError: name 'run_one_line' is not defined
Traceback (most recent call last):
File "<string>", line 1, in <module>
NameError: name 'run_one_line' is not defined
Traceback (most recent call last):
File "<string>", line 1, in <module>
NameError: name 'run_one_line' is not defined
...etc.

The errors stem from two regressions: one caused by an LLVM upgrade and one caused by unintended upgrade to SWIG 4.0 (SWIG is a wrapper generator that is used to generate Python bindings for LLVM and LLDB.)

(Edit: found the exact dates) The SWIG breakage happened because of a Homebrew version upgrade on nightly-2019-05-01-x86_64-apple-darwin and the LLVM breakage happened on nightly-2019-01-27-x86_64-apple-darwin (likely to have been caused by #57675 ).

The fix is to update the LLVM parameter syntax and to "downgrade" to SWIG 3.0.x. SWIG 3.0.x is not going to be supported by Homebrew forever, but should be good for now, until LLDB upgrades to support SWIG 4.0.0. Here's some more info about Homebrew support: Homebrew/homebrew-core#39929 & Homebrew/homebrew-core#40882 I'm going to send a bug & fix to LLDB about SWIG 4.0.0 to get the situation fixed in the future.

It would be good to also backport this to beta, since it's such a small change, and will fix an obvious regression.

[rust-highfive]

r? @nikomatsakis

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[nikomatsakis]

@bors r+

[bors]

📌 Commit 267bf7b has been approved by nikomatsakis

[nikomatsakis]

Is there any way we can test this in the future?

[golddranks]

I think we could test the basic functionality of rust-lldb using a simple shell script. I tried this locally, and it seems to work. However, know nothing about the test infrastructure. I'll ask around a bit in Discord and send a separate PR later!

[golddranks]

I noticed that this doesn't pass the dist pass correctly because the Homebrew swig@3 installation doesn't install it to PATH by default. @Centril sorry for the failing roll merges! I'll send a fix.

[rust-highfive]

Your PR failed on Travis (raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

travis_time:end:0a679640:start=1560596573215584404,finish=1560596661210865901,duration=87995281497
$ git checkout -qf FETCH_HEAD
travis_fold:end:git.checkout
Encrypted environment variables have been removed for security reasons.
See https://docs.travis-ci.com/user/pull-requests/#pull-requests-and-security-restrictions
$ export SCCACHE_BUCKET=rust-lang-ci-sccache2
$ export SCCACHE_REGION=us-west-1
$ export GCP_CACHE_BUCKET=rust-lang-ci-cache
$ export AWS_ACCESS_KEY_ID=AKIA46X5W6CZEJZ6XT55
---
travis_fold:start:before_install.3
travis_time:start:0b72f064
$ if [ "$TRAVIS_OS_NAME" = linux ]; then echo '{"ipv6":true,"fixed-cidr-v6":"fd9a:8454:6789:13f7::/64"}' | sudo tee /etc/docker/daemon.json; sudo service docker restart; fi
{"ipv6":true,"fixed-cidr-v6":"fd9a:8454:6789:13f7::/64"}
is_retry brew update && travis_retry brew install xz && travis_retry brew install swig@3; brew link --force swig@3 fi && travis_retry curl -fo /usr/local/bin/sccache https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror/2018-04-02-sccache-x86_64-apple-darwin && chmod +x /usr/local/bin/sccache && travis_retry curl -fo /usr/local/bin/stamp https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror/2017-03-17-stamp-x86_64-apple-darwin && chmod +x /usr/local/bin/stamp && travis_retry curl -f http://releases.llvm.org/7.0.0/clang+llvm-7.0.0-x86_64-apple-darwin.tar.xz | tar xJf - && export CC=`pwd`/clang+llvm-7.0.0-x86_64-apple-darwin/bin/clang && export CXX=`pwd`/clang+llvm-7.0.0-x86_64-apple-darwin/bin/clang++ && export AR=ar ;; esac '
travis_time:end:09d300a4:start=1560596668524290032,finish=1560596668527636134,duration=3346102
The command "case "$TRAVIS_OS_NAME" in linux) travis_retry curl -fo $HOME/stamp https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror/2017-03-17-stamp-x86_64-unknown-linux-musl && chmod +x $HOME/stamp && export PATH=$PATH:$HOME ;; osx) if [[ "$SCRIPT" == "./x.py dist" ]]; then travis_retry brew update && travis_retry brew install xz && travis_retry brew install swig@3; brew link --force swig@3 fi && travis_retry curl -fo /usr/local/bin/sccache https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror/2018-04-02-sccache-x86_64-apple-darwin && chmod +x /usr/local/bin/sccache && travis_retry curl -fo /usr/local/bin/stamp https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror/2017-03-17-stamp-x86_64-apple-darwin && chmod +x /usr/local/bin/stamp && travis_retry curl -f http://releases.llvm.org/7.0.0/clang+llvm-7.0.0-x86_64-apple-darwin.tar.xz | tar xJf - && export CC=`pwd`/clang+llvm-7.0.0-x86_64-apple-darwin/bin/clang && export CXX=`pwd`/clang+llvm-7.0.0-x86_64-apple-darwin/bin/clang++ && export AR=ar ;; esac" failed and exited with 1 during .
Your build has been stopped.

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @TimNN. (Feature Requests)

[golddranks]

Oops, accidentally re-based against the newest master. Shouldn't change anything though.

[golddranks]

Any news on this? I realised that the r+ doesn't apply any more since I pushed to commits to fix a problem, so this might need another review.

[pnkfelix]

discussed at T-compiler meeting. declining for backport, since the bug being fixed is not high priority and I'd prefer to let this change bake it nightly first.

[nikomatsakis]

@bors r+

[bors]

📌 Commit 2d6e1df has been approved by nikomatsakis

[bors]

⌛ Testing commit 2d6e1df with merge f693d33...

[bors]

☀️ Test successful - checks-travis, status-appveyor
Approved by: nikomatsakis
Pushing f693d33 to master...