diff --git a/library/std/src/sys/unix/args.rs b/library/std/src/sys/unix/args.rs
index 1e4c2445232..0efe2570d67 100644
--- a/library/std/src/sys/unix/args.rs
+++ b/library/std/src/sys/unix/args.rs
@@ -242,13 +242,15 @@ mod imp {
         let mut res = Vec::new();
 
         unsafe {
-            let process_info_sel = sel_registerName(c"processInfo".as_ptr());
-            let arguments_sel = sel_registerName(c"arguments".as_ptr());
-            let utf8_sel = sel_registerName(c"UTF8String".as_ptr());
-            let count_sel = sel_registerName(c"count".as_ptr());
-            let object_at_sel = sel_registerName(c"objectAtIndex:".as_ptr());
+            let process_info_sel =
+                sel_registerName(c"processInfo".as_ptr() as *const libc::c_uchar);
+            let arguments_sel = sel_registerName(c"arguments".as_ptr() as *const libc::c_uchar);
+            let utf8_sel = sel_registerName(c"UTF8String".as_ptr() as *const libc::c_uchar);
+            let count_sel = sel_registerName(c"count".as_ptr() as *const libc::c_uchar);
+            let object_at_sel =
+                sel_registerName(c"objectAtIndex:".as_ptr() as *const libc::c_uchar);
 
-            let klass = objc_getClass(c"NSProcessInfo".as_ptr());
+            let klass = objc_getClass(c"NSProcessInfo".as_ptr() as *const libc::c_uchar);
             let info = objc_msgSend(klass, process_info_sel);
             let args = objc_msgSend(info, arguments_sel);