Merge pull request #133 from dtolnay/temp

Improve error on temp value to point to the correct statement

src/macros.rs

@@ -173,8 +173,9 @@ macro_rules! anyhow {
     };
     ($err:expr $(,)?) => ({
         use $crate::private::kind::*;
-        let error = $err;
-        (&error).anyhow_kind().new(error)
+        match $err {
+            error => (&error).anyhow_kind().new(error),
+        }
     });
     ($fmt:expr, $($arg:tt)*) => {
         $crate::private::new_adhoc(format!($fmt, $($arg)*))

tests/ui/temporary-value.rs

@@ -0,0 +1,5 @@
+use anyhow::anyhow;
+
+fn main() {
+    let _ = anyhow!(&String::new());
+}

tests/ui/temporary-value.stderr

@@ -0,0 +1,8 @@
+error[E0716]: temporary value dropped while borrowed
+ --> $DIR/temporary-value.rs:4:22
+  |
+4 |     let _ = anyhow!(&String::new());
+  |             ---------^^^^^^^^^^^^^-- temporary value is freed at the end of this statement
+  |             |        |
+  |             |        creates a temporary which is freed while still in use
+  |             argument requires that borrow lasts for `'static`