Auto merge of #48925 - zackmdavis:fn_must_stabilize, r=nikomatsakis

stabilize `#[must_use]` for functions and must-use comparison operators (RFC 1940)

r? @nikomatsakis

1 files changed, 2 insertions, 0 deletions

diff --git a/src/libstd/ffi/c_str.rs b/src/libstd/ffi/c_str.rs
index 8164f52d3c3..7c358aafa9b 100644
--- a/src/libstd/ffi/c_str.rs
+++ b/src/libstd/ffi/c_str.rs
@@ -988,6 +988,7 @@ impl CStr {
     /// behavior when `ptr` is used inside the `unsafe` block:
     ///
     /// ```no_run
+    /// # #![allow(unused_must_use)]
     /// use std::ffi::{CString};
     ///
     /// let ptr = CString::new("Hello").unwrap().as_ptr();
@@ -1003,6 +1004,7 @@ impl CStr {
     /// To fix the problem, bind the `CString` to a local variable:
     ///
     /// ```no_run
+    /// # #![allow(unused_must_use)]
     /// use std::ffi::{CString};
     ///
     /// let hello = CString::new("Hello").unwrap();