use rustc version as llvm-tools version

Author: japaric

src/bootstrap/lib.rs

@@ -958,21 +958,24 @@ impl Build {
     }
 
     fn llvm_tools_vers(&self) -> String {
-        let stdout = build_helper::output(
-            Command::new(self.llvm_out(self.config.build).join("build/bin/llvm-size"))
-                .arg("--version"),
-        );
-
-        for line in stdout.lines() {
-            if line.contains("LLVM version") {
-                if let Some(vers) = line.split_whitespace().nth(2) {
-                    return vers.to_string();
-                }
-            }
-        }
-
-        panic!("The output of $LLVM_TOOL has changed; \
-                please fix `bootstrap::Build.llvm_tools_vers`");
+        // XXX should we use LLVM version here?
+        // let stdout = build_helper::output(
+        //     Command::new(self.llvm_out(self.config.build).join("build/bin/llvm-size"))
+        //         .arg("--version"),
+        // );
+
+        // for line in stdout.lines() {
+        //     if line.contains("LLVM version") {
+        //         if let Some(vers) = line.split_whitespace().nth(2) {
+        //             return vers.to_string();
+        //         }
+        //     }
+        // }
+
+        // panic!("The output of $LLVM_TOOL has changed; \
+        //         please fix `bootstrap::Build.llvm_tools_vers`");
+
+        self.rust_version()
     }
 
     /// Returns the `version` string associated with this compiler for Rust