inliner: Emit storage markers for introduced arg temporaries

When introducing argument temporaries during inlining, emit storage
marker statements just before the assignment and in the beginning of
the return block.

This ensures that such temporaries will not be considered live across
yield points after inlining inside a generator.

1 files changed, 16 insertions, 0 deletions

diff --git a/src/test/ui/mir/issue-71793-inline-args-storage.rs b/src/test/ui/mir/issue-71793-inline-args-storage.rs
new file mode 100644
index 00000000000..87b2806d4e2
--- /dev/null
+++ b/src/test/ui/mir/issue-71793-inline-args-storage.rs
@@ -0,0 +1,16 @@
+// Verifies that inliner emits StorageLive & StorageDead when introducing
+// temporaries for arguments, so that they don't become part of the generator.
+// Regression test for #71793.
+//
+// check-pass
+// edition:2018
+// compile-args: -Zmir-opt-level=2
+
+#![crate_type = "lib"]
+
+pub async fn connect() {}
+
+pub async fn connect_many() {
+    Vec::<String>::new().first().ok_or("").unwrap();
+    connect().await;
+}