diff --git a/src/lib/fs.rs b/src/lib/fs.rs
index 655994b31d96..de5bae0b50b5 100644
--- a/src/lib/fs.rs
+++ b/src/lib/fs.rs
@@ -121,11 +121,11 @@ Function: make_dir
 
 Creates a directory at the specified path.
 */
-fn make_dir(p: path, mode: int) -> bool {
+fn make_dir(p: path, mode: ctypes::c_int) -> bool {
     ret mkdir(p, mode);
 
     #[cfg(target_os = "win32")]
-    fn mkdir(_p: path, _mode: int) -> bool unsafe {
+    fn mkdir(_p: path, _mode: ctypes::c_int) -> bool unsafe {
         // FIXME: turn mode into something useful?
         ret str::as_buf(_p, {|buf|
             os::kernel32::CreateDirectoryA(
@@ -135,8 +135,8 @@ fn make_dir(p: path, mode: int) -> bool {
 
     #[cfg(target_os = "linux")]
     #[cfg(target_os = "macos")]
-    fn mkdir(_p: path, _mode: int) -> bool {
-        ret str::as_buf(_p, {|buf| os::libc::mkdir(buf, _mode) == 0 });
+    fn mkdir(_p: path, _mode: ctypes::c_int) -> bool {
+        ret str::as_buf(_p, {|buf| os::libc::mkdir(buf, _mode) == 0i32 });
     }
 }
 
@@ -174,7 +174,7 @@ fn remove_dir(p: path) -> bool {
     #[cfg(target_os = "linux")]
     #[cfg(target_os = "macos")]
     fn rmdir(_p: path) -> bool {
-        ret str::as_buf(_p, {|buf| os::libc::rmdir(buf) == 0 });
+        ret str::as_buf(_p, {|buf| os::libc::rmdir(buf) == 0i32 });
     }
 }
 
diff --git a/src/lib/linux_os.rs b/src/lib/linux_os.rs
index 255cbb974109..de655b5c12ce 100644
--- a/src/lib/linux_os.rs
+++ b/src/lib/linux_os.rs
@@ -51,8 +51,8 @@ native mod libc {
     fn pipe(buf: *mutable fd_t) -> c_int;
     fn waitpid(pid: pid_t, &status: c_int, options: c_int) -> pid_t;
     fn readlink(path: str::sbuf, buf: str::sbuf, bufsize: size_t) -> ssize_t;
-    fn mkdir(path: str::sbuf, mode: int) -> int;
-    fn rmdir(path: str::sbuf) -> int;
+    fn mkdir(path: str::sbuf, mode: c_int) -> c_int;
+    fn rmdir(path: str::sbuf) -> c_int;
 }
 
 mod libc_constants {
diff --git a/src/lib/macos_os.rs b/src/lib/macos_os.rs
index 09b7256c064e..2bd5eab93ba5 100644
--- a/src/lib/macos_os.rs
+++ b/src/lib/macos_os.rs
@@ -43,7 +43,7 @@ native mod libc {
     fn setenv(n: str::sbuf, v: str::sbuf, overwrite: c_int) -> c_int;
     fn unsetenv(n: str::sbuf) -> c_int;
     fn pipe(buf: *mutable c_int) -> c_int;
-    fn waitpid(pid: int, &status: c_int, options: c_int) -> c_int;
+    fn waitpid(pid: pid_t, &status: c_int, options: c_int) -> c_int;
     fn mkdir(s: str::sbuf, mode: c_int) -> c_int;
     fn rmdir(s: str::sbuf) -> c_int;
 }
diff --git a/src/lib/tempfile.rs b/src/lib/tempfile.rs
index 1d29169ecc4d..5f504ba23494 100644
--- a/src/lib/tempfile.rs
+++ b/src/lib/tempfile.rs
@@ -14,7 +14,7 @@ fn mkdtemp(prefix: str, suffix: str) -> option::t<str> {
     let i = 0u;
     while (i < 1000u) {
         let s = prefix + r.gen_str(16u) + suffix;
-        if fs::make_dir(s, 0x1c0) {  // FIXME: u+rwx
+        if fs::make_dir(s, 0x1c0i32) {  // FIXME: u+rwx
             ret some(s);
         }
         i += 1u;