Why does all cargo binaries have the same hash?

1

When I compute the hash of the following binaries in my .cargo/bin directory I got the same hash for all of them:

cargo-clippy.exe
cargo-fmt.exe
cargo-miri.exe
cargo.exe
clippy-driver.exe
rls.exe
rust-analyzer.exe
rust-gdb.exe
rust-gdbgui.exe
rust-lldb.exe
rustc.exe
rustdoc.exe
rustfmt.exe
rustup.exe

I'm curious to know why it's done like this and how it can work if it's all the same binary.

2

These are called proxies by rustup, AFAIK:

rustup is a toolchain multiplexer. It installs and manages many Rust toolchains and presents them all through a single set of tools installed to ~/.cargo/bin. The rustc and cargo executables installed in ~/.cargo/bin are proxies that delegate to the real toolchain. rustup then provides mechanisms to easily change the active toolchain by reconfiguring the behavior of the proxies.

~ The Rustup Book

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3

because they are actually same binary, which is rustup.

4

To clarify, rustup changes its behavior without changing its content at all by looking at the first command line argument, which is the executable's name.

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5

Ouch. Those binaries aren't really small...
Using minimal binaries that call rustup with the right parameter would save a lot of space!

6

They are hard-linked so there is actually only one copy with many names.

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7

They've recently been changed to symlinks.

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8

Indeed, they are!

I'm really surprised; I thought those were notoriously tricky to manage on Windows. But that was some time ago.

9

Rustup first tries to symlink and if that fails it hardlinks. Symlinks work on Windows when dev mode is enabled, while hardlinks always work.

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