bpf-linker core dump in aya-template generated project

[cfeitong]

This is my rustc version:

Default host: x86_64-unknown-linux-gnu
rustup home:  /home/cfeitong/.rustup

nightly-x86_64-unknown-linux-gnu (default)
rustc 1.58.0-nightly (dd549dcab 2021-11-25)

I just run cargo xtask build-ebpf and come across following error:

cargo xtask build-ebpf
    Finished dev [unoptimized + debuginfo] target(s) in 0.03s
     Running `target/debug/xtask build-ebpf`
       Fresh core v0.0.0 (/home/cfeitong/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core)
       Fresh unicode-xid v0.2.2
       Fresh rustc-std-workspace-core v1.99.0 (/home/cfeitong/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/rustc-std-workspace-core)
       Fresh compiler_builtins v0.1.52
       Fresh proc-macro2 v1.0.32
       Fresh quote v1.0.10
       Fresh aya-bpf-cty v0.2.1 (http://github.com/aya-rs/aya?branch=main#98b36b23)
       Fresh aya-try-common v0.1.0 (/home/cfeitong/aya-try/aya-try-common)
       Fresh syn v1.0.82
       Fresh aya-bpf-bindings v0.1.0 (http://github.com/aya-rs/aya?branch=main#98b36b23)
       Fresh aya-bpf-macros v0.1.0 (http://github.com/aya-rs/aya?branch=main#98b36b23)
       Fresh aya-bpf v0.1.0 (http://github.com/aya-rs/aya?branch=main#98b36b23)
   Compiling aya-try-ebpf v0.1.0 (/home/cfeitong/aya-try/aya-try-ebpf)
     Running `rustc --crate-name aya_try --edition=2018 src/main.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C opt-level=2 -C panic=abort -C embed-bitcode=no -C debuginfo=1 -C debug-assertions=on -C overflow-checks=off -C metadata=36fb82a4cf69a379 -C extra-filename=-36fb82a4cf69a379 --out-dir /home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps --target bpfel-unknown-none -C incremental=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/incremental -L dependency=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps -L dependency=/home/cfeitong/aya-try/aya-try-ebpf/../target/debug/deps --extern aya_bpf=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libaya_bpf-54640d6e071de353.rlib --extern aya_try_common=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libaya_try_common-356f6b2922032732.rlib --extern 'noprelude:compiler_builtins=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libcompiler_builtins-177c1b24e4b8b2db.rlib' --extern 'noprelude:core=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libcore-2c13aef38b676b75.rlib' -Z unstable-options`
error: linking with `bpf-linker` failed: signal: 6 (core dumped)
  |
  = note: "bpf-linker" "--export-symbols" "/tmp/rustcgdWOgi/symbols" "/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/aya_try-36fb82a4cf69a379.17dzbhexels5i7io.rcgu.o" "-L" "/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps" "-L" "/home/cfeitong/aya-try/aya-try-ebpf/../target/debug/deps" "-L" "/home/cfeitong/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/bpfel-unknown-none/lib" "/home/cfeitong/aya-try/target/bpfel-unknown-none/debug/deps/libaya_bpf-54640d6e071de353.rlib" "/home/cfeitong/aya-try/target/bpfel-unknown-none/debug/deps/libaya_bpf_bindings-be43530adef294a6.rlib" "/home/cfeitong/aya-try/target/bpfel-unknown-none/debug/deps/libaya_bpf_cty-b7d399661acdd31b.rlib" "/home/cfeitong/aya-try/target/bpfel-unknown-none/debug/deps/librustc_std_workspace_core-51eb0738dcf81a45.rlib" "/home/cfeitong/aya-try/target/bpfel-unknown-none/debug/deps/libcore-2c13aef38b676b75.rlib" "/home/cfeitong/aya-try/target/bpfel-unknown-none/debug/deps/libcompiler_builtins-177c1b24e4b8b2db.rlib" "--cpu" "generic" "--cpu-features" "" "-L" "/home/cfeitong/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/bpfel-unknown-none/lib" "-o" "/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/aya_try-36fb82a4cf69a379" "-O2" "--debug"
  = note: 09:11:02 [ERROR] fatal error: "Cannot select: 0x55f68fc8fd58: i64,ch = AtomicLoad<(load unordered (s64) from %ir.45)> 0x55f68e76e978, 0x55f68fc90100\n  0x55f68fc90100: i64,ch = CopyFromReg 0x55f68e76e978, Register:i64 %19\n    0x55f68fc904a8: i64 = Register %19\nIn function: memcpy"
          PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
          Stack dump:
          0.    Running pass 'Function Pass Manager' on module 'aya_try-36fb82a4cf69a379'.
          1.    Running pass 'BPF DAG->DAG Pattern Instruction Selection' on function '@memcpy'
          

error: could not compile `aya-try-ebpf` due to previous error

Caused by:
  process didn't exit successfully: `rustc --crate-name aya_try --edition=2018 src/main.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C opt-level=2 -C panic=abort -C embed-bitcode=no -C debuginfo=1 -C debug-assertions=on -C overflow-checks=off -C metadata=36fb82a4cf69a379 -C extra-filename=-36fb82a4cf69a379 --out-dir /home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps --target bpfel-unknown-none -C incremental=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/incremental -L dependency=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps -L dependency=/home/cfeitong/aya-try/aya-try-ebpf/../target/debug/deps --extern aya_bpf=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libaya_bpf-54640d6e071de353.rlib --extern aya_try_common=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libaya_try_common-356f6b2922032732.rlib --extern 'noprelude:compiler_builtins=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libcompiler_builtins-177c1b24e4b8b2db.rlib' --extern 'noprelude:core=/home/cfeitong/aya-try/aya-try-ebpf/../target/bpfel-unknown-none/debug/deps/libcore-2c13aef38b676b75.rlib' -Z unstable-options` (exit status: 1)
thread 'main' panicked at 'assertion failed: status.success()', xtask/src/build_ebpf.rs:62:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[alessandrod]

Thanks for the report and sorry about the trouble! This is a known bug that is getting fixed in the rust compiler, see rust-lang/compiler-builtins#440.

In the meantime you can workaround the problem building the ebpf code with:

cd aya-try-ebpf
cargo rustc -- -C link-arg=--disable-memory-builtins

instead of running cargo xtask build-ebpf.

[alessandrod]

This is now fixed in rust nightly rust-lang/rust#91248