rustc on Mac OS X: "unknown option --as-needed"

[cflewis]

When trying to cross-compile to a new target (installed by rustup) it looks like --as-needed is spawned by rustc, but this isn't available on Mac OS X (El Capitain)

❯ cargo build --target=mipsel-unknown-linux-gnu -v
   Compiling tessel v0.1.0 (file:///Users/cflewis/Documents/Computing/rust/tessel)
     Running `rustc src/main.rs --crate-name tessel --crate-type bin -g --out-dir /Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug --emit=dep-info,link --target mipsel-unknown-linux-gnu -L dependency=/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug -L dependency=/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug/deps`
error: linking with `cc` failed: exit code: 1
note: "cc" "-Wl,--as-needed" "-Wl,-z,noexecstack" "-L" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib" "/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug/tessel.0.o" "-o" "/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug/tessel" "-Wl,--gc-sections" "-pie" "-nodefaultlibs" "-L" "/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug" "-L" "/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug/deps" "-L" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib" "-Wl,-Bstatic" "-Wl,-Bdynamic" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/libstd-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/libcollections-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/librustc_unicode-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/librand-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/liballoc-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/liballoc_jemalloc-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/liblibc-d16b8f0e.rlib" "/Users/cflewis/.multirust/toolchains/stable-x86_64-apple-darwin/lib/rustlib/mipsel-unknown-linux-gnu/lib/libcore-d16b8f0e.rlib" "-l" "dl" "-l" "pthread" "-l" "gcc_s" "-l" "pthread" "-l" "c" "-l" "m" "-l" "rt" "-l" "util" "-l" "compiler-rt"
note: clang: warning: argument unused during compilation: '-pie'
ld: unknown option: --as-needed
clang: error: linker command failed with exit code 1 (use -v to see invocation)

error: aborting due to previous error
error: Could not compile `tessel`.

Caused by:
  Process didn't exit successfully: `rustc src/main.rs --crate-name tessel --crate-type bin -g --out-dir /Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug --emit=dep-info,link --target mipsel-unknown-linux-gnu -L dependency=/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug -L dependency=/Users/cflewis/Documents/Computing/rust/tessel/target/mipsel-unknown-linux-gnu/debug/deps` (exit code: 101)

[eefriedman]

When you're cross-compiling, you have to point cargo at an appropriate C toolchain, to pick up necessary bits like the correct linker and C runtime. See also http://blog.rust-lang.org/2016/05/13/rustup.html , in particular the discussion of the "linker" option.

[alexcrichton]

Yeah currently this is expected, albeit unfortunate, behavior. As @eefriedman mentioned the key thing here is finding a linker for mipsel-unknown-linux-gnu which the native system linker doesn't support on OSX.

As this is expected, though, I'm gonna close this, but feel free to ask questions! Unfortunately I've never heard of anyone successfully crossing from OSX to mips Linux, but in theory it's definitely possible!

[samuela]

Following https://github.com/chinedufn/cross-compile-rust-from-mac-to-linux, the following worked for me:

$ rustup target add x86_64-unknown-linux-gnu
$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu
$ CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_LINKER=x86_64-unknown-linux-gnu-gcc cargo build --release --target=x86_64-unknown-linux-gnu

[Banyc]

It would be great if rustup target add x86_64-unknown-linux-gnu could handle this problem for me.

[yiya1989]

Following https://github.com/chinedufn/cross-compile-rust-from-mac-to-linux, the following worked for me:

$ rustup target add x86_64-unknown-linux-gnu
$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu
$ CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_LINKER=x86_64-unknown-linux-gnu-gcc cargo build --release --target=x86_64-unknown-linux-gnu

Thanks for your reply, I tried add these to .cargo/config.toml, it works.

$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu

# .cargo/config.toml
[build]
target = "x86_64-unknown-linux-gnu"

[target.x86_64-unknown-linux-gnu]
linker = "/usr/local/bin/x86_64-unknown-linux-gnu-gcc"

[jiakuan]

Following https://github.com/chinedufn/cross-compile-rust-from-mac-to-linux, the following worked for me:

$ rustup target add x86_64-unknown-linux-gnu
$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu
$ CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_LINKER=x86_64-unknown-linux-gnu-gcc cargo build --release --target=x86_64-unknown-linux-gnu

Thanks for your reply, I tried add these to .cargo/config.toml, it works.

$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu

# .cargo/config.toml
[build]
target = "x86_64-unknown-linux-gnu"

[target.x86_64-unknown-linux-gnu]
linker = "/usr/local/bin/x86_64-unknown-linux-gnu-gcc"

Thanks for sharing. It worked for me as well, although the linker path is a bit different for me:

[target.x86_64-unknown-linux-gnu]
linker = "/opt/homebrew/bin/x86_64-unknown-linux-gnu-gcc"

[lovelock]

It would be great if rustup target add x86_64-unknown-linux-gnu could handle this problem for me.

From a newbie's perspective, rustup target add should solve this kind of problems, or why would I add the target😄? BTW, the brew tap above solved my problem too.

[lovelock]

Following https://github.com/chinedufn/cross-compile-rust-from-mac-to-linux, the following worked for me:

$ rustup target add x86_64-unknown-linux-gnu
$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu
$ CARGO_TARGET_X86_64_UNKNOWN_LINUX_GNU_LINKER=x86_64-unknown-linux-gnu-gcc cargo build --release --target=x86_64-unknown-linux-gnu

Thanks for your reply, I tried add these to .cargo/config.toml, it works.

$ brew tap SergioBenitez/osxct
$ brew install x86_64-unknown-linux-gnu

# .cargo/config.toml
[build]
target = "x86_64-unknown-linux-gnu"

[target.x86_64-unknown-linux-gnu]
linker = "/usr/local/bin/x86_64-unknown-linux-gnu-gcc"

Thanks for sharing. It worked for me as well, although the linker path is a bit different for me:

[target.x86_64-unknown-linux-gnu]
linker = "/opt/homebrew/bin/x86_64-unknown-linux-gnu-gcc"

It's a homebrew issue, don't know it's about homebrew version or macOS version and it confuses me when I write scripts for both my M1 laptop (macOS 13.4) and Intel desktop(macOS 12.6)

[phial3]

cargo build --target x86_64-unknown-linux-gnu on MacOS M2 error:
"ld: unknown option: --as-needed", problems remain