Switch to cfg_if!

src/unix/linux_like/emscripten/mod.rs

@@ -26,10 +26,13 @@ pub type clock_t = c_long;
 //  And it's still int64 today. The change from long to int was marked as a
 //  nonfunctional change since wasm64 was considered to be not working yet in
 //  v3.1.11. So it suffices to say it's 32 bit until v3.1.16 and 64 bit after.
-#[cfg(emscripten_64_bit_time_t)]
-pub type time_t = i64;
-#[cfg(not(emscripten_64_bit_time_t))]
-pub type time_t = i32;
+cfg_if! {
+    if #[cfg(emscripten_64_bit_time_t)] {
+        pub type time_t = i64;
+    } else {
+        pub type time_t = i32;
+    }
+}
 
 pub type suseconds_t = c_long;
 pub type ino_t = u64;