diff options
| -rw-r--r-- | src/libcore/macros/mod.rs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/libcore/macros/mod.rs b/src/libcore/macros/mod.rs index 18d5eaa9648..8de6be86e34 100644 --- a/src/libcore/macros/mod.rs +++ b/src/libcore/macros/mod.rs @@ -1159,6 +1159,10 @@ pub(crate) mod builtin { /// The syntax given to this macro is the same syntax as the [`cfg`] /// attribute. /// + /// `cfg!`, unlike `#[cfg]`, does not remove any code and only evaluates to true or false. For + /// example, this means all code in an if/else block needs to be valid when `cfg!` is used for + /// the condition, regardless of what `cfg!` is evaluating. + /// /// [`cfg`]: ../reference/conditional-compilation.html#the-cfg-attribute /// /// # Examples |