Failed to run example-kernels

I run in an issue by the attempt to run example-kernels and hope to find help this way.
The cli cargo bootimage --target x86_64-bootimage-example-kernels.json finished successfully, but cargo xrun failed

✔ ~/git/github/rust-osdev/bootimage/example-kernels [master|✔] 
14:47 $ git log --oneline -n1
d590098 (HEAD -> master, origin/master, origin/HEAD) CI: Use choco to install QEMU 6.0.0
✔ ~/git/github/rust-osdev/bootimage/example-kernels [master|✔] 
14:47 $ cargo xrun --target x86_64-bootimage-example-kernels.json
WARNING: There is no root package to read the cargo-xbuild config from.
   Compiling core v0.0.0 (/home/XXX/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core)
   Compiling compiler_builtins v0.1.49
   Compiling rustc-std-workspace-core v1.99.0 (/home/XXX/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/rustc-std-workspace-core)
error[E0465]: multiple rmeta candidates for `core` found
 --> /home/XXX/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/rustc-std-workspace-core/lib.rs:4:9
  |
4 | pub use core::*;
  |         ^^^^
  |
note: candidate #1: /tmp/cargo-xbuild0mSUnk/target/x86_64-bootimage-example-kernels/release/deps/libcore-8386ca77507e6ddc.rmeta
 --> /home/XXX/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/rustc-std-workspace-core/lib.rs:4:9
  |
4 | pub use core::*;
  |         ^^^^
note: candidate #2: /tmp/cargo-xbuild0mSUnk/target/x86_64-bootimage-example-kernels/release/deps/libcore-cb62582e916e4b2a.rmeta
 --> /home/XXX/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/rustc-std-workspace-core/lib.rs:4:9
  |
4 | pub use core::*;
  |         ^^^^

error: could not compile `rustc-std-workspace-core` due to previous error
warning: build failed, waiting for other jobs to finish...
error: build failed
error: `"/home/XXX/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/cargo" "rustc" "-p" "alloc" "--release" "--manifest-path" "/tmp/cargo-xbuild0mSUnk/Cargo.toml" "--target" "x86_64-bootimage-example-kernels.json" "--" "-Z" "force-unstable-if-unmarked"` failed with exit code: Some(101)

Reproduce the failure in example-kernels by running cargo bootimage --target x86_64-bootimage-example-kernels.json followed by cargo xrun --target x86_64-bootimage-example-kernels.json. Start with the reported multiple rmeta candidates for core error and compare the two build paths. Done means cargo xrun completes successfully for this target.