Link iconv on macOS via build.rs

build.rs

@@ -10,6 +10,7 @@ fn main() {
     let const_extern_fn_cargo_feature =
         env::var("CARGO_FEATURE_CONST_EXTERN_FN").is_ok();
     let libc_ci = env::var("LIBC_CI").is_ok();
+    let target = env::var("TARGET").unwrap();
 
     if env::var("CARGO_FEATURE_USE_STD").is_ok() {
         println!(
@@ -82,6 +83,10 @@ fn main() {
         }
         println!("cargo:rustc-cfg=libc_const_extern_fn");
     }
+
+    if target.contains("-apple-") {
+        println!("cargo:rustc-link-lib=iconv");
+    }
 }
 
 fn rustc_minor_nightly() -> Option<(u32, bool)> {

src/unix/mod.rs

@@ -297,10 +297,8 @@ cfg_if! {
     if #[cfg(target_os = "l4re")] {
         // required libraries for L4Re are linked externally, ATM
     } else if #[cfg(feature = "std")] {
-        // cargo build. Most libraries are already pulled in by libstd dep
-        #[cfg_attr(
-            any(target_os = "macos", target_os = "ios"),
-            link(name = "iconv"))]
+        // cargo build, don't pull in anything extra as the libstd dep
+        // already pulls in all libs.
         extern {}
     } else if #[cfg(all(target_os = "linux",
                         target_env = "gnu",