diff --git a/src/chmod/chmod.rs b/src/chmod/chmod.rs
index 363562213..5b869f129 100644
--- a/src/chmod/chmod.rs
+++ b/src/chmod/chmod.rs
@@ -78,7 +78,7 @@ Each MODE is of the form '[ugoa]*([-+=]([rwxXst]*|[ugo]))+|[-+=]?[0-7]+'.",
         let recursive = matches.opt_present("recursive");
         let fmode = matches.opt_str("reference").and_then(|fref| {
             let mut stat : libc::stat = unsafe { mem::uninitialized() };
-            let statres = unsafe { libc::stat(fref.as_ptr() as *const i8, &mut stat as *mut libc::stat) };
+            let statres = unsafe { libc::stat(fref.as_ptr() as *const _, &mut stat as *mut libc::stat) };
             if statres == 0 {
                 Some(stat.st_mode)
             } else {
diff --git a/src/id/id.rs b/src/id/id.rs
index 7e9e89b70..bbf2de03f 100644
--- a/src/id/id.rs
+++ b/src/id/id.rs
@@ -191,7 +191,7 @@ fn pretty(possible_pw: Option<c_passwd>) {
         print!("uid\t{}\ngroups\t", pw_name);
         group(possible_pw, true);
     } else {
-        let login = unsafe { String::from_utf8_lossy(CStr::from_ptr((getlogin() as *const i8)).to_bytes()).to_string() };
+        let login = unsafe { String::from_utf8_lossy(CStr::from_ptr((getlogin() as *const _)).to_bytes()).to_string() };
         let rid = unsafe { getuid() };
         let pw = unsafe { getpwuid(rid) };
 
diff --git a/src/uname/uname.rs b/src/uname/uname.rs
index 78106e8f2..ef67e522b 100644
--- a/src/uname/uname.rs
+++ b/src/uname/uname.rs
@@ -35,7 +35,7 @@ extern {
 }
 
 unsafe fn string_from_c_str(ptr: *const i8) -> String {
-    String::from_utf8_lossy(CStr::from_ptr(ptr).to_bytes()).to_string()
+    String::from_utf8_lossy(CStr::from_ptr(ptr as *const std::os::raw::c_char).to_bytes()).to_string()
 }
 
 unsafe fn getuname() -> Uts {
diff --git a/src/uucore/c_types.rs b/src/uucore/c_types.rs
index 54478a107..cdc8b3649 100644
--- a/src/uucore/c_types.rs
+++ b/src/uucore/c_types.rs
@@ -128,7 +128,7 @@ pub fn get_pw_from_args(free: &Vec<String>) -> Option<c_passwd> {
         } else {
             let pw_pointer = unsafe {
                 let cstr = CString::new(username).unwrap();
-                getpwnam(cstr.as_bytes_with_nul().as_ptr() as *const i8)
+                getpwnam(cstr.as_bytes_with_nul().as_ptr() as *const _)
             };
             if !pw_pointer.is_null() {
                 Some(unsafe { read(pw_pointer) })