Add x86_64-unknown-linux-none target

compiler/rustc_target/src/spec/mod.rs

@@ -1774,6 +1774,9 @@ supported_targets! {
     ("aarch64-unknown-linux-ohos", aarch64_unknown_linux_ohos),
     ("armv7-unknown-linux-ohos", armv7_unknown_linux_ohos),
     ("x86_64-unknown-linux-ohos", x86_64_unknown_linux_ohos),
+
+    ("x86_64-unknown-linux-none", x86_64_unknown_linux_none),
+
 }
 
 /// Cow-Vec-Str: Cow<'static, [Cow<'static, str>]>

compiler/rustc_target/src/spec/targets/x86_64_unknown_linux_none.rs

@@ -0,0 +1,25 @@
+use crate::spec::{base, Cc, LinkerFlavor, Lld, StackProbeType, Target};
+
+pub fn target() -> Target {
+    let mut base = base::linux::opts();
+    base.cpu = "x86-64".into();
+    base.max_atomic_width = Some(64);
+    base.stack_probes = StackProbeType::Inline;
+    base.linker_flavor = LinkerFlavor::Gnu(Cc::No, Lld::Yes);
+    base.linker = Some("rust-lld".into());
+
+    Target {
+        llvm_target: "x86_64-unknown-linux-none".into(),
+        metadata: crate::spec::TargetMetadata {
+            description: None,
+            tier: None,
+            host_tools: None,
+            std: None,
+        },
+        pointer_width: 64,
+        data_layout:
+            "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128".into(),
+        arch: "x86_64".into(),
+        options: base,
+    }
+}