Work around linking issues from rust-fuzz/afl.rs#141, rust-lang/rust#53945

src/bin/cargo-afl.rs

@@ -190,6 +190,12 @@ where
        common::afl_llvm_rt_dir().display()
    );

    // work around https://github.com/rust-fuzz/afl.rs/issues/141 /
    // https://github.com/rust-lang/rust/issues/53945, can be removed once
    // those are fixed.
    rustflags.push_str("-Clink-arg=-fuse-ld=gold");
    rustdocflags.push_str("-Clink-arg=-fuse-ld=gold");

    // add user provided flags
    rustflags.push_str(&env::var("RUSTFLAGS").unwrap_or_default());
    rustdocflags.push_str(&env::var("RUSTDOCFLAGS").unwrap_or_default());