can't work because of rust-lang/rfcs#1053

but would be cool
coherent backtrace implementation for Compat<failure::Error>

src/compat.rs

@@ -1,47 +1,54 @@
 use core::fmt::{self, Display};
 
+use Error;
+use Fail;
+
 /// A compatibility wrapper around an error type from this crate.
 ///
 /// `Compat` implements `std::error::Error`, allowing the types from this
 /// crate to be passed to interfaces that expect a type of that trait.
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash, Default)]
 pub struct Compat<E> {
-    pub(crate) error: E,
+	pub(crate) error: E,
 }
 
 impl<E: Display> Display for Compat<E> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        Display::fmt(&self.error, f)
-    }
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		Display::fmt(&self.error, f)
+	}
 }
 
 impl<E> Compat<E> {
-    /// Unwraps this into the inner error.
-    pub fn into_inner(self) -> E {
-        self.error
-    }
-
-    /// Gets a reference to the inner error.
-    pub fn get_ref(&self) -> &E {
-        &self.error
-    }
+	/// Unwraps this into the inner error.
+	pub fn into_inner(self) -> E {
+		self.error
+	}
+
+	/// Gets a reference to the inner error.
+	pub fn get_ref(&self) -> &E {
+		&self.error
+	}
+}
+
+impl Fail for Compat<Error> {
+	fn backtrace(&self) -> Option<&crate::Backtrace> {
+		Some(self.error.backtrace())
+	}
 }
 
 with_std! {
-    use std::fmt::Debug;
-    use std::error::Error as StdError;
-
-    use Error;
-
-    impl<E: Display + Debug> StdError for Compat<E> {
-        fn description(&self) -> &'static str {
-            "An error has occurred."
-        }
-    }
-
-    impl From<Error> for Box<StdError> {
-        fn from(error: Error) -> Box<StdError> {
-            Box::new(Compat { error })
-        }
-    }
+	use std::fmt::Debug;
+	use std::error::Error as StdError;
+
+	impl<E: Display + Debug> StdError for Compat<E> {
+		fn description(&self) -> &'static str {
+			"An error has occurred."
+		}
+	}
+
+	impl From<Error> for Box<StdError> {
+		fn from(error: Error) -> Box<StdError> {
+			Box::new(Compat { error })
+		}
+	}
 }