minimal_build

.cargo/config.toml

@@ -0,0 +1,5 @@
+[unstable]
+build-std-features = ["compiler-builtins-mem"]
+build-std = ["core", "compiler_builtins"]
+[build]
+target = "x86-roxy.json"

src/main.rs

@@ -0,0 +1,21 @@
+#![no_std]
+#![no_main]
+#![feature(custom_test_frameworks)]
+#![test_runner(test_runner)]
+
+use core::panic::PanicInfo;
+
+#[no_mangle]
+pub extern "C" fn _start() -> ! {
+    loop {}
+}
+
+#[panic_handler]
+fn panic(_info: &PanicInfo) -> ! { // "!" is never type, since function should never return anything
+    loop {}
+}
+
+#[cfg(test)]
+fn test_runner(_test: &[&dyn Fn()]) {
+    loop {}
+}

x86-roxy.json

@@ -0,0 +1,15 @@
+{
+    "llvm-target": "x86_64-unknown-none",
+    "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",
+    "arch": "x86_64",
+    "target-endian": "little",
+    "target-pointer-width": "64",
+    "target-c-int-width": "32",
+    "os": "none",
+    "executables": true,
+    "linker-flavor": "ld.lld",
+    "linker": "rust-lld",
+    "panic-strategy": "abort",
+    "disable-redzone": true,
+    "features": "-mmx,-sse,+soft-float"
+}