diff --git a/library/alloc/src/string.rs b/library/alloc/src/string.rs
index 71b6b9b41f5c5..8ef25b86cdb4c 100644
--- a/library/alloc/src/string.rs
+++ b/library/alloc/src/string.rs
@@ -607,17 +607,7 @@ impl String {
     #[cfg(not(no_global_oom_handling))]
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn from_utf16(v: &[u16]) -> Result<String, FromUtf16Error> {
-        // This isn't done via collect::<Result<_, _>>() for performance reasons.
-        // FIXME: the function can be simplified again when #48994 is closed.
-        let mut ret = String::with_capacity(v.len());
-        for c in decode_utf16(v.iter().cloned()) {
-            if let Ok(c) = c {
-                ret.push(c);
-            } else {
-                return Err(FromUtf16Error(()));
-            }
-        }
-        Ok(ret)
+        decode_utf16(v.iter().cloned()).collect::<Result<_, _>>().map_err(|_| FromUtf16Error(()))
     }
 
     /// Decode a UTF-16–encoded slice `v` into a `String`, replacing