diff --git a/library/core/tests/num/mod.rs b/library/core/tests/num/mod.rs
index 378c8af344b59..190528fd445bf 100644
--- a/library/core/tests/num/mod.rs
+++ b/library/core/tests/num/mod.rs
@@ -27,6 +27,8 @@ mod bignum;
 mod dec2flt;
 mod flt2dec;
 
+mod nan;
+
 /// Adds the attribute to all items in the block.
 macro_rules! cfg_block {
     ($(#[$attr:meta]{$($it:item)*})*) => {$($(