From f36f52091c94fdefa03068646cb13533d312109f Mon Sep 17 00:00:00 2001
From: Philipp Hansch <dev@phansch.net>
Date: Sat, 24 Aug 2019 21:42:39 +0200
Subject: [PATCH] Fix unused_unit false positive

Fixes #4076
---
 clippy_lints/src/returns.rs |  2 +-
 tests/ui/unused_unit.rs     | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/clippy_lints/src/returns.rs b/clippy_lints/src/returns.rs
index 3cc053a0ebf6..e864518ee598 100644
--- a/clippy_lints/src/returns.rs
+++ b/clippy_lints/src/returns.rs
@@ -277,7 +277,7 @@ impl EarlyLintPass for Return {
         if_chain! {
             if let Some(ref stmt) = block.stmts.last();
             if let ast::StmtKind::Expr(ref expr) = stmt.node;
-            if is_unit_expr(expr) && !expr.span.from_expansion();
+            if is_unit_expr(expr) && !stmt.span.from_expansion();
             then {
                 let sp = expr.span;
                 span_lint_and_then(cx, UNUSED_UNIT, sp, "unneeded unit expression", |db| {
diff --git a/tests/ui/unused_unit.rs b/tests/ui/unused_unit.rs
index 1acd427be1ee..e361755d50e0 100644
--- a/tests/ui/unused_unit.rs
+++ b/tests/ui/unused_unit.rs
@@ -43,3 +43,16 @@ fn main() {
     }
     return();
 }
+
+// https://github.com/rust-lang/rust-clippy/issues/4076
+fn foo() {
+    macro_rules! foo {
+        (recv($r:expr) -> $res:pat => $body:expr) => {
+            $body
+        }
+    }
+
+    foo! {
+        recv(rx) -> _x => ()
+    }
+}