Use throw intrinsic from stdarch in wasm libunwind

[coolreader18]

Tracking issue: #118168

This is a very belated followup to #121438; now that rust-lang/stdarch#1542 is merged, we can use the intrinsic exported from core::arch instead of defining it inline. I also cleaned up the cfgs a bit and added a more detailed comment.

[rustbot]

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[coolreader18]

or actually r? @bjorn3

[rust-log-analyzer]

The job x86_64-gnu-llvm-18 failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

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 > importing cache manifest from ghcr.io/rust-lang/rust-ci-cache:20950f2ccee3dff53a038adf5c1cf05231c0b30772617126a5f6478a66316a29cba9aead69f7bb0004886d32c1f8e6287542cf6d25130711c82d16a66201d4fe:
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##[endgroup]
Setting extra environment values for docker:  --env ENABLE_GCC_CODEGEN=1 --env GCC_EXEC_PREFIX=/usr/lib/gcc/
[CI_JOB_NAME=x86_64-gnu-llvm-18]
/checkout/src/ci/run.sh: line 58: DISABLE_CI_RUSTC_IF_INCOMPATIBLE: command not found
debug:  configured.
---
sccache: Starting the server...
##[group]Configure the build
configure: processing command line
configure: 
configure: build.configure-args := ['--build=x86_64-unknown-linux-gnu', '--llvm-root=/usr/lib/llvm-18', '--enable-llvm-link-shared', '--set', 'rust.randomize-layout=true', '--set', 'rust.thin-lto-import-instr-limit=10', '--set', 'change-id=99999999', '--enable-verbose-configure', '--enable-sccache', '--disable-manage-submodules', '--enable-locked-deps', '--enable-cargo-native-static', '--set', 'rust.codegen-units-std=1', '--set', 'dist.compression-profile=balanced', '--dist-compression-formats=xz', '--set', 'rust.lld=false', '--disable-dist-src', '--release-channel=nightly', '--enable-debug-assertions', '--enable-overflow-checks', '--enable-llvm-assertions', '--set', 'rust.verify-llvm-ir', '--set', 'rust.codegen-backends=llvm,cranelift,gcc', '--set', 'llvm.static-libstdcpp', '--enable-new-symbol-mangling']
configure: target.x86_64-unknown-linux-gnu.llvm-config := /usr/lib/llvm-18/bin/llvm-config
configure: llvm.link-shared     := True
configure: rust.randomize-layout := True
configure: rust.thin-lto-import-instr-limit := 10
---
  Downloaded boml v0.3.1
   Compiling boml v0.3.1
   Compiling y v0.1.0 (/checkout/compiler/rustc_codegen_gcc/build_system)
    Finished `release` profile [optimized] target(s) in 3.74s
     Running `/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-codegen/x86_64-unknown-linux-gnu/release/y test --use-system-gcc --use-backend gcc --out-dir /checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools/cg_gcc --release --mini-tests --std-tests`
Using system GCC
[BUILD] example
[AOT] mini_core_hello_world
/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools/cg_gcc/mini_core_hello_world
abc
---
##[group]Building stage1 library artifacts (x86_64-unknown-linux-gnu)
##[endgroup]
##[group]Building tool rustdoc (stage0 -> stage1, x86_64-unknown-linux-gnu)
##[endgroup]
thread 'core::builder::tests::ci_rustc_if_unchanged_logic' panicked at src/core/builder/tests.rs:260:5:
assertion failed: has_changes == config.download_rustc_commit.is_none()


failures:
    core::builder::tests::ci_rustc_if_unchanged_logic

[coolreader18]

That... seems unrelated to my changes?

[coolreader18]

Ah that's what the linked PR is

[bjorn3]

@bors r+

[bors]

📌 Commit 35d9bdb has been approved by bjorn3

It is now in the queue for this repository.