diff --git a/src/libcore/mem.rs b/src/libcore/mem.rs
index 93f6a0214d77d487b67edf144bce2d8875dc167a..21a0beccbf64d604e32dcfbfd86daa9da116197c 100644
--- a/src/libcore/mem.rs
+++ b/src/libcore/mem.rs
@@ -189,6 +189,7 @@ pub fn forget<T>(t: T) {
 /// Type | size_of::\<Type>()
 /// ---- | ---------------
 /// () | 0
+/// bool | 1
 /// u8 | 1
 /// u16 | 2
 /// u32 | 4