diff --git a/src/unistd/src/lib.rs b/src/unistd/src/lib.rs
index 2071c6f42afdaa069b261c72ee43fc21cd56c9a1..c6a85a53a59a6f7e6611c89da9e0afc095a4b46c 100644
--- a/src/unistd/src/lib.rs
+++ b/src/unistd/src/lib.rs
@@ -33,7 +33,7 @@ pub const STDOUT_FILENO: c_int = 1;
 pub const STDERR_FILENO: c_int = 2;
 
 #[no_mangle]
-pub static mut environ: *const *mut c_char = 0 as *const *mut c_char;
+pub static mut environ: *const *mut c_char = ptr::null();
 
 #[no_mangle]
 pub extern "C" fn _exit(status: c_int) {