Build glue for pre-kstart early init asm code - is this a viable way to do it ?

gistfile1.txt

diff --git a/Cargo.toml b/Cargo.toml
index 45a5681..7a57d03 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,7 @@
 [package]
 name = "kernel"
 version = "0.1.32"
+links = "early_init"
 build = "build.rs"
 
 [lib]
@@ -14,6 +15,10 @@ bitflags = "1"
 spin = "0.4"
 redox_syscall = { path = "syscall" }
 
+[build-dependencies]
+cc = "1.0.3"
+rustc-cfg = "0.3.0"
+
 [target.'cfg(target_arch = "x86_64")'.dependencies]
 raw-cpuid = "3.0"
 x86 = "0.7"
diff --git a/build.rs b/build.rs
index 4efa33e..acd48d5 100644
--- a/build.rs
+++ b/build.rs
@@ -3,7 +3,10 @@ use std::fs;
 use std::io::{Error, Write};
 use std::path::Path;
 use std::collections::HashMap;
+use rustc_cfg::Cfg;
 
+extern crate cc;
+extern crate rustc_cfg;
 
 // View loc folder with subfolders, get listings
 // Returns touple (folder_map, file_list)
@@ -117,4 +120,12 @@ mod gen {
     }
 }
 ").unwrap();
+
+    // Build pre kstart init asm code
+    let cfg = Cfg::new(env::var_os("TARGET").unwrap()).unwrap();
+    if cfg.target_arch == "aarch64" {
+        cc::Build::new()
+            .file("src/arch/arm64/early_init.S")
+            .compile("early_init");
+    }
 }
diff --git a/linkers/aarch64.ld b/linkers/aarch64.ld
index eb9d7af..d1cdbee 100644
--- a/linkers/aarch64.ld
+++ b/linkers/aarch64.ld
@@ -1,4 +1,4 @@
-ENTRY(kstart)
+ENTRY(early_init)
 OUTPUT_FORMAT("elf64-littleaarch64", "elf64-littleaarch64", "elf64-littleaarch64")
 
 KERNEL_OFFSET = 0xffffff0000100000;
diff --git a/src/arch/arm64/early_init.S b/src/arch/arm64/early_init.S
new file mode 100644
index 0000000..b3b2d06
--- /dev/null
+++ b/src/arch/arm64/early_init.S
@@ -0,0 +1,5 @@
+    .text
+    .globl early_init
+early_init:
+    b kstart