Support configurations with the specific Rust version

Author: denzp

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rustc-llvm-proxy"
-version = "0.1.7"
+version = "0.1.8"
 authors = ["Denys Zariaiev <[email protected]>"]
 license = "MIT"
 

build.rs

@@ -22,7 +22,6 @@ fn main() {
     }
 
     println!("cargo:rerun-if-changed=build.rs");
-    println!("cargo:rerun-if-changed={}/llvm_gen.rs", out_dir);
 
     llvm::Generator::default()
         .parse_llvm_sys_crate()

src/path.rs

@@ -123,5 +123,15 @@ fn collect_possible_paths() -> Result<Vec<PathBuf>, Error> {
 }
 
 fn extract_arch(toolchain: &str) -> String {
-    toolchain.split('-').skip(1).collect::<Vec<_>>().join("-")
+    toolchain
+        .split('-')
+        // Skip `nightly` rust version prefix.
+        .skip(1)
+        // Also skip rust version specification if exists.
+        .skip_while(|item| match item.chars().next() {
+            None | Some('0'...'9') => true,
+            _ => false,
+        })
+        .collect::<Vec<_>>()
+        .join("-")
 }