`lib/rustlib/<arch>/bin/gcc-ld/ld` should be wrapped for `-Clinker-flavor=gcc-lld`

[oxalica]

The option is available on nightly now: rust-lang/rust#85961
And it may be enabled by default on Ubuntu in the future: rust-lang/rust#71515

Currently the ld executable (actually lld) runs but failed to find C libraries. It should to be wrapped by wrapBintoolsWith.

[sledgehammervampire]

Wait, so -Z gcc-ld=lld not working for C libraries might be a Nix thing, and not rustc in general?

Edit: Nope. I tried -C link-arg=-fuse-ld=lld, which I think uses the nixpkgs lld, and my project with a C dependency doesn't work, unlike without the flag.

[oxalica]

Wait, so -Z gcc-ld=lld not working for C libraries might be a Nix thing, and not rustc in general?

It's not about C libraries. Currently it doesn't work for a simple rust hello world program, since std requires -lc.

I tried -C link-arg=-fuse-ld=lld, which I think uses the nixpkgs lld

It may be another issue. Currently I'm using the rust-lld shipped by rust toolchain with some manual wrapping and it works fine with things like openssl. But of course, you still need nix-shell -p openssl pkg-config to let the build script find the library first.

[sledgehammervampire]

On my machine, using -Z gcc-ld=lld and -C link-arg=-fuse-ld=lld with the Rust from this overlay works for pure-Rust projects. Does it not work for you?

[oxalica]

On my machine, using -Z gcc-ld=lld and -C link-arg=-fuse-ld=lld with the Rust from this overlay works for pure-Rust projects.

Oh yes, it seems working now. Weird.

I also tested openssl which links to C library. It also works fine in nix-shell -p openssl pkg-config environment.

[sledgehammervampire]

Hmm, that's strange. When I use a dependency with openssl-sys, say reqwest 0.11.4, I get this error when running a compiled program:

target/debug/downloader: error while loading shared libraries: libssl.so.1.1: cannot open shared object file: No such file or directory