diff --git a/compiler/src/dotty/tools/dotc/transform/TailRec.scala b/compiler/src/dotty/tools/dotc/transform/TailRec.scala
index b6b51d54d95b..bc3a251065cf 100644
--- a/compiler/src/dotty/tools/dotc/transform/TailRec.scala
+++ b/compiler/src/dotty/tools/dotc/transform/TailRec.scala
@@ -407,8 +407,11 @@ class TailRec extends MiniPhase {
           assert(false, "We should never have gotten inside a pattern")
           tree
 
-        case _: ValDef | _: DefDef | _: Super | _: This |
-             _: Literal | _: TypeTree | _: TypeDef | EmptyTree =>
+        case tree: ValOrDefDef =>
+          if (isMandatory) noTailTransform(tree.rhs)
+          tree
+
+        case _: Super | _: This | _: Literal | _: TypeTree | _: TypeDef | EmptyTree =>
           tree
 
         case Labeled(bind, expr) =>
diff --git a/tests/neg-tailcall/t1672b.scala b/tests/neg-tailcall/t1672b.scala
index fa1b12c57cbd..84ebb6155e6d 100644
--- a/tests/neg-tailcall/t1672b.scala
+++ b/tests/neg-tailcall/t1672b.scala
@@ -43,12 +43,12 @@ object Test1772B {
 
   // the `liftedTree` local method will prevent a tail call here.
   @tailrec
-  def bar(i : Int) : Int = { // error: TailRec optimisation not applicable
+  def bar(i : Int) : Int = {
     if (i == 0) 0
     else 1 + (try {
       throw new RuntimeException
     } catch {
-      case _: Throwable => bar(i - 1) // old error: cannot rewrite recursive call
+      case _: Throwable => bar(i - 1) // error: it is not in tail position
     })
   }
 }
diff --git a/tests/neg/i5397.scala b/tests/neg/i5397.scala
new file mode 100644
index 000000000000..d38b0e67bff9
--- /dev/null
+++ b/tests/neg/i5397.scala
@@ -0,0 +1,41 @@
+import annotation.tailrec
+
+object Test {
+  def foo(x: => Int) = 1
+  def bar(x: Int => Int) = 1
+
+  @tailrec def rec1: Int =
+    foo(rec1) // error: not in tail position
+
+  @tailrec def rec2: Int =
+    bar(_ => rec2) // error: not in tail position
+
+  @tailrec def rec3: Int =
+    1 + (try ??? catch {
+      case _: Throwable =>
+        rec3 // error: not in tail position
+    })
+
+  @tailrec def rec4: Unit = {
+    def local = rec4 // error: not in tail position
+  }
+
+  @tailrec def rec5: Int = {
+    val x = {
+      rec5 // error: not in tail position
+      1
+    }
+    x
+  }
+}
+
+object Test4649 {
+  @tailrec
+  def lazyFilter[E](s: Stream[E], p: E => Boolean): Stream[E] = s match {
+    case h #:: t =>
+      if (p(h)) h #:: lazyFilter(t, p) // error: not in tail position
+      else lazyFilter(t, p)
+    case _ =>
+      Stream.empty
+  }
+}
diff --git a/tests/pos/ErasureAnd.scala b/tests/pos/ErasureAnd.scala
index 38c5f4c94ea0..1c86ee4b9086 100644
--- a/tests/pos/ErasureAnd.scala
+++ b/tests/pos/ErasureAnd.scala
@@ -1,6 +1,4 @@
-import scala.annotation.tailrec
 trait A { self: B =>
-  @tailrec
   private def foo(arg1: Int, arg2: Int): Int = {
     def bar = this.foo(arg1, arg2)
     foo(arg1, arg2)
diff --git a/tests/pos/tailcall/t4649.scala b/tests/pos/tailcall/t4649.scala
deleted file mode 100644
index 12ebe095894b..000000000000
--- a/tests/pos/tailcall/t4649.scala
+++ /dev/null
@@ -1,29 +0,0 @@
-import annotation.tailrec
-
-object Test4649 {
-  @tailrec
-  def lazyFilter[E](s: Stream[E], p: E => Boolean): Stream[E] = s match {
-    case h #:: t =>
-      if (p(h)) h #:: lazyFilter(t, p) // Ok: not a tail call but in a closure
-      else lazyFilter(t, p)
-    case _ =>
-      Stream.empty
-  }
-
-  def cond: Boolean = ???
-  def foo(x: => Int): Int = ???
-
-  @tailrec
-  def bar: Int = {
-    if (cond) foo(bar) // Ok: not a tail call but in a closure
-    else bar
-  }
-
-  def foo2(x: Int => Int) = ???
-
-  @tailrec
-  def bar2: Int = {
-    if (cond) foo2(_ => bar2) // Ok: not a tail call but in a closure
-    else bar2
-  }
-}