Auto merge of #60547 - redox-os:redox-unix, r=alexcrichton

redox: convert to target_family unix

This is the second step to supporting #60139.

In order to have a smooth transition, there will need to be a change made in liblibc at the same time, switching Redox over to the unix target family. See rust-lang/libc#1332

src/libpanic_abort/lib.rs

@@ -48,8 +48,7 @@ pub unsafe extern fn __rust_start_panic(_payload: usize) -> u32 {
         libc::abort();
     }
 
-    #[cfg(any(target_os = "redox",
-              windows,
+    #[cfg(any(windows,
               all(target_arch = "wasm32", not(target_os = "emscripten"))))]
     unsafe fn abort() -> ! {
         core::intrinsics::abort();

src/librustc_target/spec/aarch64_unknown_redox.rs

@@ -0,0 +1,20 @@
+use crate::spec::{LinkerFlavor, Target, TargetResult};
+
+pub fn target() -> TargetResult {
+    let mut base = super::redox_base::opts();
+    base.max_atomic_width = Some(128);
+
+    Ok(Target {
+        llvm_target: "aarch64-unknown-redox".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "64".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128".to_string(),
+        arch: "aarch64".to_string(),
+        target_os: "redox".to_string(),
+        target_env: "relibc".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: base,
+    })
+}

src/librustc_target/spec/mod.rs

@@ -417,6 +417,7 @@ supported_targets! {
 
     ("x86_64-unknown-l4re-uclibc", x86_64_unknown_l4re_uclibc),
 
+    ("aarch64-unknown-redox", aarch64_unknown_redox),
     ("x86_64-unknown-redox", x86_64_unknown_redox),
 
     ("i386-apple-ios", i386_apple_ios),

src/librustc_target/spec/redox_base.rs

@@ -1,4 +1,4 @@
-use crate::spec::{LinkArgs, LinkerFlavor, TargetOptions};
+use crate::spec::{LinkArgs, LinkerFlavor, TargetOptions, RelroLevel};
 use std::default::Default;
 
 pub fn opts() -> TargetOptions {
@@ -18,14 +18,17 @@ pub fn opts() -> TargetOptions {
     ]);
 
     TargetOptions {
-        pre_link_args: args,
+        dynamic_linking: true,
         executables: true,
-        relocation_model: "static".to_string(),
-        disable_redzone: true,
-        eliminate_frame_pointer: false,
-        target_family: None,
+        target_family: Some("unix".to_string()),
         linker_is_gnu: true,
+        has_rpath: true,
+        pre_link_args: args,
+        position_independent_executables: true,
+        relro_level: RelroLevel::Full,
         has_elf_tls: true,
+        crt_static_default: true,
+        crt_static_respected: true,
         .. Default::default()
     }
 }

src/librustc_target/spec/x86_64_unknown_redox.rs

@@ -15,7 +15,7 @@ pub fn target() -> TargetResult {
         data_layout: "e-m:e-i64:64-f80:128-n8:16:32:64-S128".to_string(),
         arch: "x86_64".to_string(),
         target_os: "redox".to_string(),
-        target_env: String::new(),
+        target_env: "relibc".to_string(),
         target_vendor: "unknown".to_string(),
         linker_flavor: LinkerFlavor::Gcc,
         options: base,

src/libstd/os/mod.rs

@@ -50,6 +50,7 @@ cfg_if::cfg_if! {
 #[cfg(target_os = "emscripten")] pub mod emscripten;
 #[cfg(target_os = "fuchsia")]    pub mod fuchsia;
 #[cfg(target_os = "hermit")]     pub mod hermit;
+#[cfg(target_os = "redox")]      pub mod redox;
 #[cfg(target_os = "wasi")]       pub mod wasi;
 #[cfg(target_os = "vxworks")]    pub mod vxworks;
 #[cfg(all(target_vendor = "fortanix", target_env = "sgx"))] pub mod fortanix_sgx;