wasi-sdk/bin/wasm-ld regression in 1.46.0

[TjeuKayim]

I tried to cross compile a hello world with WASI SDK as explained at https://doc.rust-lang.org/nightly/nightly-rustc/rustc_target/spec/wasm32_wasi/index.html:

cargo init
wget https://github.com/WebAssembly/wasi-sdk/releases/download/wasi-sdk-11/wasi-sdk_11.0_amd64_ubuntu20.04.deb
sudo dpkg -i wasi-sdk_11.0_amd64_ubuntu20.04.deb
rm wasi-sdk_11.0_amd64_ubuntu20.04.deb
export CC_wasm32_wasi=/opt/wasi-sdk/bin/clang
export CARGO_TARGET_WASM32_WASI_LINKER=/opt/wasi-sdk/bin/clang
cargo build --target wasm32-wasi

I expected to see this happen: the build succeeds with Rust v1.45.2 , so next versions should be compatible.

Instead, this happened when updating to Rust v1.46.0: https://github.com/TjeuKayim/wasi-link-fail/runs/1109104907

error: linking with `/opt/wasi-sdk/bin/clang` failed: exit code: 1
##[error]  |
  = note: wasm-ld: error: unknown argument: --eh-frame-hdr
          clang-10: error: linker command failed with exit code 1 (use -v to see invocation)

And 1.48.0-nightly (2020-09-12) produces another error: https://github.com/TjeuKayim/wasi-link-fail/runs/1109104926

error: linking with `/opt/wasi-sdk/bin/clang` failed: exit code: 1
##[error]  |
  = note: wasm-ld: error: std-5fceb8daecdd3ed8.std.5ro3oaeh-cgu.0.rcgu.o: Bad relocation type: 
          clang-10: error: linker command failed with exit code 1 (use -v to see invocation)

A weird exception is my Manjaro Linux system with Rust 1.46.0, it only builds succesfully when I add RUSTFLAGS='-C link-args=-Wl,-v'. I have no clue why, and couldn't reproduce this on Ubuntu.

See this repository for a minimal reproduction https://github.com/TjeuKayim/wasi-link-fail.

[mati865]

--eh-frame-hdr was recently fixed on nightly: #76307

[LeSeulArtichaut]

@TjeuKayim is your issue fixed on the latest nightly?

[TjeuKayim]

is your issue fixed on the latest nightly?

No, rust version 1.48.0-nightly (6af1bdda5 2020-09-15) is still affected.
I ran the Github Action again https://github.com/TjeuKayim/wasi-link-fail/runs/1122804715, the same error appeared:

  = note: wasm-ld: error: std-5fceb8daecdd3ed8.std.5ro3oaeh-cgu.0.rcgu.o: Bad relocation type: 
          clang-10: error: linker command failed with exit code 1 (use -v to see invocation)

[TjeuKayim]

The bisection below seems to point to the introduction of the other eh-frame-hr regression, that's useless. To bisect the other regression that causes this issue, it needs to apply the #76307 patch on rustc before testing, but I don't now how to execute such bisection.

searched nightlies: from nightly-2020-06-30 to nightly-2020-07-30
regressed nightly: nightly-2020-07-03
searched commits: from f781bab to 3503f56
regressed commit: 8a6d434

bisected with cargo-bisect-rustc v0.5.2

Host triple: x86_64-unknown-linux-gnu
Reproduce with:

cargo bisect-rustc --start=2020-06-30 --end=2020-07-30 --target wasm32-wasi -- build --target wasm32-wasi