Limit storage duration of inlined always live locals

src/test/ui/mir/auxiliary/issue_76375_aux.rs

@@ -1,8 +1,8 @@
 // edition:2018
-// compile-flags: -Z mir-opt-level=2 -Z unsound-mir-opts
+// compile-flags: -Z mir-opt-level=2
 
 #[inline(always)]
-pub fn f(s: bool) -> String {
+pub fn copy_prop(s: bool) -> String {
     let a = "Hello world!".to_string();
     let b = a;
     let c = b;
@@ -12,3 +12,9 @@ pub fn f(s: bool) -> String {
         String::new()
     }
 }
+
+#[inline(always)]
+pub fn dest_prop(x: &[u8]) -> &[u8] {
+    let y = &x[..x.len()];
+    y
+}

src/test/ui/mir/issue-76375.rs

@@ -1,6 +1,8 @@
+// Regression test for issue #76375.
+//
 // edition:2018
 // build-pass
-// compile-flags: -Z mir-opt-level=2 -L.
+// compile-flags: -Z mir-opt-level=2
 // aux-build:issue_76375_aux.rs
 
 #![crate_type = "lib"]
@@ -8,8 +10,18 @@
 extern crate issue_76375_aux;
 
 pub async fn g() {
-    issue_76375_aux::f(true);
+    issue_76375_aux::copy_prop(true);
     h().await;
 }
 
+pub async fn u() {
+    let b = [0u8; 32];
+    let mut i = 0;
+    while i != 10 {
+        issue_76375_aux::dest_prop(&b);
+        h().await;
+        i += 1;
+    }
+}
+
 pub async fn h() {}