"LLVM ERROR: Access past stack top!" when compiling without sse2

[nivkner]

the following code produces the compilation error LLVM ERROR: Access past stack top! when compiling with E:RUSTFLAGS="-Ctarget-feature=-sse2" cargo +nightly run

fn main() {
    let (a, b) = get_pair();
}

fn get_pair() -> (f64, f64) {
    (0.0, 0.0)
}

only happens when the return values of get_pair are named.

also when compiling an example to a library crate like this: E:RUSTFLAGS="-Ctarget-feature=-sse2" cargo +nightly run --example bug

i get the following error instead:

process didn't exit successfully: `rustc --edition=2018 --crate-name bug examples/bug.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C debuginfo=2 -C metadata=6421b7fc9708c373 -C extra-filename=-6421b7fc9708c373 --out-dir /home/user/Documents/bug_lib/target/debug/examples -C incremental=/home/user/Documents/bug_lib/target/debug/incremental -L dependency=/home/user/Documents/bug_lib/target/debug/deps --extern bug_lib=/home/user/Documents/bug_lib/target/debug/deps/libbug_lib-f0c2fba934c178d2.rlib -Ctarget-feature=-sse2` (signal: 11, SIGSEGV: invalid memory reference)

rustc version:

rustc 1.40.0-nightly (246be7e1a 2019-10-25)
binary: rustc
commit-hash: 246be7e1a557b8ac8287c6842379a0db67770be6
commit-date: 2019-10-25
host: x86_64-unknown-linux-gnu
release: 1.40.0-nightly
LLVM version: 9.0

[jonas-schievink]

Does this also happen on older Rust versions?

[mati865]

AFAIK it affects all Rust versions since 1.18.0.

[pnkfelix]

@rustbot ping ICEbreakers-LLVM

[rustbot]

Error: This team (ICEbreakers-LLVM) cannot be pinged via this command;it may need to be added to triagebot.toml on the master branch.

Please let @rust-lang/release know if you're having trouble with this bot.

[pnkfelix]

@rustbot ping icebreakers-llvm

[rustbot]

Hey LLVM ICE-breakers! This bug has been identified as a good
"LLVM ICE-breaking candidate". In case it's useful, here are some
instructions for tackling these sorts of bugs. Maybe take a look?
Thanks! <3

cc @hdhoang @heyrutvik @jryans @mmilenko @nagisa @nikic @rkruppe @spastorino @vertexclique

[pnkfelix]

triage: P-high, removing I-nominated