rustc_trans: support ZST indexing involving uninhabited types.
Fixes#46855 in a minimal way. I decided against supporting non-memory `Rvalue::Len` in this PR (see https://github.com/rust-lang/rust/issues/46855#issuecomment-352965807), as `PlaceContext::Inspect` is also used for `Rvalue::Discriminant`.
r? @arielb1
rustc: don't use union layouts for tagged union enums.
Fixes#46897, fixes#43517 (AFAICT from the testcases).
This PR doesn't add any testcases, we should try to at least get perf ones (cc @Mark-Simulacrum).
I couldn't find an example in those issues where the choice of LLVM array vs struct (with N identical fields) for padding filler types is still needed, *on top of* this change, to prevent excessive LLVM sinking.
r? @arielb1
Make the output of the column! macro 1 based
Fixes #46868.
I didn't add any regression tests as the change already had to change tests inside the codebase.
r? @dtolnay
[MIR Borrowck] Moveck inline asm statements
Closes#45695
New behavior:
* Input operands to `asm!` are moved, direct output operands are initialized.
* Direct, non-read-write outputs match the assignment changes in #46752 (Shallow writes, end borrows).
Solves incorrect diagnostics for unused or deprecated imports. Closes#46576.
Deprecated imports had an existing test which asserted the incorrect span.
That test has been corrected as part of this commit.
[auto-toolstate] Upload the toolstate result to an external git repository, and removes BuildExpectation
This PR consists of 3 commits.
1. (Steps 4–6) The `toolstate.json` output previously collected is now pushed to the https://github.com/rust-lang-nursery/rust-toolstate repository.
2. (Step 7) Revert commit ab018c7, thus removing all traces of `BuildExpectation` and `toolstate.toml`.
3. (Step 8) Adjust CONTRIBUTION.md for the new procedure.
These are the last steps of #45861. After this PR, the toolstate will be automatically computed and published to https://rust-lang-nursery.github.io/rust-toolstate/. There is no need to manage toolstate.toml again.
Closes#45861.
This reverts commit ab018c76e1.
This also adds the `ToolBuild::is_ext_tool` field to replace the previous
`ToolBuild::expectation` field, to indicate whether a build-failure of
certain tool is essential.
Re-do the FreeBSD cross-builds to use Clang and libc++. Fixes#44433
Reviving #45077, from @jld:
> The main goal here is to use FreeBSD's normal libc++, instead of
> statically linking the libstdc++ packaged with GCC, because that
> libstdc++ has bugs that cause rustc to deadlock inside LLVM.
>
> But the easiest way to use libc++ is to switch the build from GCC to
> Clang, and the Clang package in the Ubuntu image already knows how to
> cross-compile (given a sysroot and preferably cross-binutils), so the
> toolchain script now uses that instead of building a custom compiler.
>
> This also de-duplicates the build-toolchain.sh script.
#45077 was close but didn't quite make it. I rebased @jld's work off the current `master` and started with that.
I was able to determine that this Travis error (https://github.com/rust-lang/rust/pull/45077#issuecomment-336029862) was ultimately caused by `src/librustc_llvm/build.rs` attempting to follow a wrong value in `LLVM_STATIC_STDCPP` (https://github.com/rust-lang/rust/pull/45077#issuecomment-352639456).
I looked at the downstream port for FreeBSD (https://svnweb.freebsd.org/ports/head/lang/rust/) and it seems like they do not use `--enable-llvm-static-stdcpp`.
Since `libc++` is included in the FreeBSD 10+ base system, we don't need to statically link it either?
So in b989428f7d I have set the FreeBSD build to not actually use `LLVM_STATIC_STDCPP`.
I was able to run `./src/ci/docker/run.sh` with both `dist-i686-freebsd` and `dist-x86_64-freebsd` successfully and in about 1 minute of testing it seemed like the dist-x86_64-freebsd results worked on a FreeBSD 11 system.
It should fix#44433, which seems to be affecting many potential users. Also FreeBSD users should be able to `./x.py build` which should help anyone who wants to upstream fixes for FreeBSD.
Questions:
Does this approach seem to be the right way to go? Do we actually really want to statically link `libc++`? (I tried that here, but it ultimately ran into a roadblock on x86_64: https://github.com/rust-lang/rust/pull/45077#issuecomment-353293414)
Can we rewrite the comment here to be more clear about why some systems aren't going to actually use this option:
b989428f7d/src/bootstrap/compile.rs (L550-L553)
How does this affect users of older FreeBSD systems? It seemed like no one was complaining about using a 10.3 base version in the thread for #45077. FreeBSD seems to only officially support 10.3, 10.4, and 11.x right now, do we have to consider older users? The `libc++` stuff came in for FreeBSD 10, older FreeBSD used `libstdc++`.
Looks like @alexcrichton was leading the discussion on the previous issue:
r? @alexcrichton
Let me know what I can do to help get this through.
