Can't link hello_world program on Windows: /usr/bin/link: extra operand

Question

I installed Rust on a Windows 10 machine with rustup-init.exe - the method recommended in the Rust Book. The installer told me that Rust needs C-runtime of VS2013 or newer. I have VS2017 installed, I assumed Rust doesn't support VS2017 yet and so agreed to install C-runtime. Installation finished successfully.

main.rs:

fn main() {
    println!("Hello, world!");
}

Compiling:

> rustc main.rs
error: linking with `link.exe` failed: exit code: 1
  |
  = note: "link.exe" "/NOLOGO" "/NXCOMPAT" "/LIBPATH:C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib" "main.0.o" "/OUT:main.exe" "/OPT:REF,NOICF" "/DEBUG" "/LIBPATH:C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libstd-0a78323911070f99.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\librand-c279a51d66700350.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libcollections-d7bf31a4ca1ea637.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libstd_unicode-d367c3ba0db49600.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libpanic_unwind-2d4bf02140c11dcb.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libunwind-add7a84d7e82d084.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\liblibc-84688accbc86d6b7.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\liballoc-fe2e68b21f0bdd7a.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\liballoc_system-7fc0381594c93f56.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libcore-ea9d77e7c23fe65c.rlib" "C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libcompiler_builtins-91b619d34dd1f5aa.rlib" "advapi32.lib" "ws2_32.lib" "userenv.lib" "shell32.lib" "msvcrt.lib"
  = note: /usr/bin/link: extra operand '/LIBPATH:C:\\Users\\***\\.rustup\\toolchains\\stable-x86_64-pc-windows-msvc\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib'
          Try '/usr/bin/link --help' for more information.

error: aborting due to previous error

link.exe LIBPATH arg is specified twice.

What's going on?

> rustc --version
rustc 1.17.0 (56124baa9 2017-04-24)

Answer 1

As the rustup documentation says:

As mentioned on the Rust download page, there are two ABIs in use on Windows: the native (MSVC) ABI used by Visual Studio, and the GNU ABI used by the GCC toolchain. Which version of Rust you need depends largely on what C/C++ libraries you want to interoperate with: for interop with software produced by Visual Studio use the MSVC build of Rust; for interop with GNU software built using the MinGW/MSYS2 toolchain use the GNU build.

You have installed the MSVC toolchain. However, you are running the the compiler in a command shell where link.exe does not point to the MSVC linker, but instead to a GNU toolchain — MSVC does not call its linker /usr/bin/link or use options like --help!

You should configure your shell so the MSVC linker is foremost in the PATH or switch to the GNU ABI if that's your goal.

Compare the help output of the two:

$ link --help
    Usage: link FILE1 FILE2
      or:  link OPTION
    Call the link function to create a link named FILE2 to an existing FILE1.

          --help     display this help and exit
          --version  output version information and exit

    GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
    Full documentation at: <http://www.gnu.org/software/coreutils/link>
    or available locally via: info '(coreutils) link invocation'

> link /help
Microsoft (R) Incremental Linker Version 14.10.25017.0
Copyright (C) Microsoft Corporation.  All rights reserved.

   For help on Linker, type `link /link' or `link'
   For help on Library Manager, type `link /lib' or `lib'
   For help on Dumper, type `link /dump' or `dumpbin'
   For help on Editor, type `link /edit' or `editbin'
   For help on CvtCIL, type `link /cvtcil'

I assumed Rust doesn't support VS2017 yet

It supports VS2017 just fine; as described in the 1.17 release notes, the problem is that it cannot automatically find the MSVC installation due to changes in where MSVC installs. Running the Rust compiler from inside a shell that has the proper environment works fine.