'internal error: entered unreachable code' when uninstalling a toolchain on Windows

[LFalch]

I'm running Windows 10.

When trying to run rustup toolchain uninstall stable-i686-pc-windows-gnu with RUST_BACKTRACE=1, I got:

thread '<main>' panicked at 'internal error: entered unreachable code', src/rustup-cli\rustup_mode.rs:42
stack backtrace:
   0:           0x72eafa - std::panicking::default_hook::_$u7b$$u7b$closure$u7d$$u7d$::hca543c34f11229ac
   1:           0x72e015 - std::panicking::default_hook::hc2c969e7453d080c
   2:           0x6f286f - std::sys_common::unwind::begin_unwind_inner::h30e12d15ce2b2e25
   3:           0x4248b3 - std::sys_common::unwind::begin_unwind::h65390c63b501d6ed
   4:           0x40c633 - rustup_init::rustup_mode::main::h904c4ed7acbad99d
   5:           0x4023a4 - rustup_init::run_multirust::h70cbf6663515e18b
   6:           0x401501 - rustup_init::main::h81d74e5ca7cf36c2
   7:           0x72d66d - std::sys_common::unwind::try::hae2ea22cfba6ab9a
   8:           0x72d49a - std::rt::lang_start::h61f4934e780b4dfc
   9:           0x4013b4 - _tmainCRTStartup
  10:           0x4014e7 - mainCRTStartup
  11:     0x7ffedaa18101 - IsPipeliningPossible.isra.5

Rustup version:

rustup 0.1.12 (c6e430a 2016-05-12)

[corvinux]

Something similar happened to me on my Linux kalix 4.3.0-kali1-amd64 #1 SMP Debian 4.3.5-1kali1 (2016-02-11) x86_64 GNU/Linux, also trying to uninstall toolchain.

root@kalix:~# rustup
rustup 0.1.12 (c6e430a 2016-05-12)
The Rust toolchain installer

USAGE:
rustup [FLAGS] [SUBCOMMAND]

FLAGS:
-v, --verbose Enable verbose output
-h, --help Prints help information
-V, --version Prints version information

SUBCOMMANDS:
show Show the active and installed toolchains
update Update Rust toolchains
default Set the default toolchain
toolchain Modify or query the installed toolchains
target Modify a toolchain's supported targets
override Modify directory toolchain overrides
run Run a command with an environment configured for a given toolchain
which Display which binary will be run for a given command
doc Open the documentation for the current toolchain.
self Modify the rustup installation
telemetry rustup telemetry commands
help Prints this message or the help of the given subcommand(s)

rustup installs The Rust Programming Language from the official
release channels, enabling you to easily switch between stable, beta,
and nightly compilers and keep them updated. It makes cross-compiling
simpler with binary builds of the standard library for common platforms.

If you are new to Rust consider running rustup doc --book
to learn Rust.

root@kalix:~# rustup show

installed toolchains

stable-x86_64-unknown-linux-gnu (default)
beta-x86_64-unknown-linux-gnu
nightly-x86_64-unknown-linux-gnu

active toolchain

stable-x86_64-unknown-linux-gnu (default)
rustc 1.9.0 (e4e8b6668 2016-05-18)

root@kalix:# rustup toolchain uninstall beta-x86_64-unknown-linux-gnu
thread '

' panicked at 'internal error: entered unreachable code', src/rustup-cli/rustup_mode.rs:42
note: Run with RUST_BACKTRACE=1 for a backtrace.
root@kalix:# RUST_BACKTRACE=1 rustup toolchain uninstall beta-x86_64-unknown-linux-gnu
thread '' panicked at 'internal error: entered unreachable code', src/rustup-cli/rustup_mode.rs:42
stack backtrace:
1: 0x556e1f212ed0 - std::sys::backtrace::tracing::imp::write::h9fb600083204ae7f
2: 0x556e1f21b16b - std::panicking::default_hook::_$u7b$$u7b$closure$u7d$$u7d$::hca543c34f11229ac
3: 0x556e1f21adf3 - std::panicking::default_hook::hc2c969e7453d080c
4: 0x556e1f2012ef - std::sys_common::unwind::begin_unwind_inner::h30e12d15ce2b2e25
5: 0x556e1ee4aaff - std::sys_common::unwind::begin_unwind::h65390c63b501d6ed
6: 0x556e1ee32513 - rustup_init::rustup_mode::main::h904c4ed7acbad99d
7: 0x556e1ee2a665 - rustup_init::run_multirust::h70cbf6663515e18b
8: 0x556e1ee29ae1 - rustup_init::main::h81d74e5ca7cf36c2
9: 0x556e1f21aa34 - std::sys_common::unwind::try::try_fn::h04c0c89e4add6cc4
10: 0x556e1f21221b - __rust_try
11: 0x556e1f21a47b - std::rt::lang_start::h61f4934e780b4dfc
12: 0x7fb4100c05ef - __libc_start_main
13: 0x556e1ee299d4 -

[brson]

Should be fixed now.