diff --git a/src/lib.rs b/src/lib.rs
index 234a642c9d489ce5f71c59a00c3986c9aae56858..793cf5231726450dd67ba96fd4e2cc5937d15e24 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5778,6 +5778,9 @@ pub mod funcs {
             use types::os::arch::posix88::{gid_t, off_t, pid_t};
             use types::os::arch::posix88::{ssize_t, uid_t};
 
+            #[cfg(target_os = "macos")]
+            pub const _PC_NAME_MAX: c_int = 3;
+            #[cfg(target_os = "linux")]
             pub const _PC_NAME_MAX: c_int = 4;
 
             #[cfg(not(target_os = "nacl"))]