diff --git a/library/alloc/src/fmt.rs b/library/alloc/src/fmt.rs
index 6f96a271442c..3697ee3d3509 100644
--- a/library/alloc/src/fmt.rs
+++ b/library/alloc/src/fmt.rs
@@ -201,6 +201,7 @@
 //!         and before the digits. When used together with the `#` flag, a similar
 //!         rule applies: padding zeros are inserted after the prefix but before
 //!         the digits. The prefix is included in the total width.
+//!         This flag overrides the [fill character and alignment flag](#fillalignment).
 //!
 //! ## Precision
 //!