Added a regression test for https://github.com/dotnet/roslyn/issues/25024

src/Compilers/CSharp/Test/Emit/CodeGen/CodeGenRefReturnTests.cs

@@ -3590,5 +3590,95 @@ static void Main()
 Program+RefFunc1`2[Derived1,Base]", verify: Verification.Passes);
         }
 
+        [WorkItem(25024, "https://github.com/dotnet/roslyn/issues/25024")]
+        [Fact]
+        public void RefReturnDiscardLifetime()
+        {
+            var text = @"
+    class Program
+    {
+        static bool flag = true;
+
+        public static void Main()
+        {
+            if (flag)
+            {
+                ref var local1 = ref M1(out var _);
+                ref var local2 = ref M1(out var _);
+
+                local1 = 1;
+                local2 = 2;
+                System.Console.Write(local1 + local2);
+            }
+
+            if (flag)
+            {
+                ref var local1 = ref M1(out var _);
+                ref var local2 = ref M1(out var _);
+
+                local1 = 3;
+                local2 = 4;
+                System.Console.Write(local1 + local2);
+            }
+        }
+
+        public static ref int M1(out int arg)
+        {
+            arg = 123;
+            return ref arg;
+        }
+       
+    }
+";
+
+            CompileAndVerifyRef(text, expectedOutput:"37", verify: Verification.Fails).VerifyIL("Program.Main()", @"
+{
+  // Code size       75 (0x4b)
+  .maxstack  3
+  .locals init (int& V_0, //local2
+                int V_1,
+                int V_2,
+                int& V_3, //local2
+                int V_4,
+                int V_5)
+  IL_0000:  ldsfld     ""bool Program.flag""
+  IL_0005:  brfalse.s  IL_0025
+  IL_0007:  ldloca.s   V_1
+  IL_0009:  call       ""ref int Program.M1(out int)""
+  IL_000e:  ldloca.s   V_2
+  IL_0010:  call       ""ref int Program.M1(out int)""
+  IL_0015:  stloc.0
+  IL_0016:  dup
+  IL_0017:  ldc.i4.1
+  IL_0018:  stind.i4
+  IL_0019:  ldloc.0
+  IL_001a:  ldc.i4.2
+  IL_001b:  stind.i4
+  IL_001c:  ldind.i4
+  IL_001d:  ldloc.0
+  IL_001e:  ldind.i4
+  IL_001f:  add
+  IL_0020:  call       ""void System.Console.Write(int)""
+  IL_0025:  ldsfld     ""bool Program.flag""
+  IL_002a:  brfalse.s  IL_004a
+  IL_002c:  ldloca.s   V_4
+  IL_002e:  call       ""ref int Program.M1(out int)""
+  IL_0033:  ldloca.s   V_5
+  IL_0035:  call       ""ref int Program.M1(out int)""
+  IL_003a:  stloc.3
+  IL_003b:  dup
+  IL_003c:  ldc.i4.3
+  IL_003d:  stind.i4
+  IL_003e:  ldloc.3
+  IL_003f:  ldc.i4.4
+  IL_0040:  stind.i4
+  IL_0041:  ldind.i4
+  IL_0042:  ldloc.3
+  IL_0043:  ldind.i4
+  IL_0044:  add
+  IL_0045:  call       ""void System.Console.Write(int)""
+  IL_004a:  ret
+}");
+        }
     }
 }