Link openlibm only in libstd

src/librustc_back/target/redox_base.rs

@@ -33,10 +33,6 @@ pub fn opts() -> TargetOptions {
             // Static link
             "-static".to_string()
         ],
-        late_link_args: vec![
-            // Link to openlibm for math functions
-            "-lopenlibm".to_string()
-        ],
         executables: true,
         relocation_model: "static".to_string(),
         disable_redzone: true,

src/libstd/build.rs

@@ -62,6 +62,8 @@ fn main() {
         println!("cargo:rustc-link-lib=magenta");
         println!("cargo:rustc-link-lib=mxio");
         println!("cargo:rustc-link-lib=launchpad"); // for std::process
+    } else if target.contains("redox") {
+        println!("cargo:rustc-link-lib=openlibm");
     }
 }