also fixes nim-lang#14420

Author: timotheecour

tests/misc/taddr.nim

@@ -124,6 +124,52 @@ block:
     when false:
       proc byLent2[T](a: T): lent type(a[0]) = a[0]
 
+proc test14420() = # bug #14420
+  # s/proc/template/ would hit bug #16005
+  block:
+    type Foo = object
+      x: float
+
+    proc fn(a: var Foo): var float =
+      ## WAS: discard <- turn this into a comment (or a `discard`) and error disappears
+      # result = a.x # this works
+      a.x #  WAS: Error: limited VM support for 'addr'
+
+    proc fn2(a: var Foo): var float =
+      result = a.x # this works
+      a.x #  WAS: Error: limited VM support for 'addr'
+
+    var a = Foo()
+    discard fn(a)
+    discard fn2(a)
+
+  block:
+    proc byLent2[T](a: T): lent T =
+      runnableExamples: discard
+      a
+    proc byLent3[T](a: T): lent T =
+      runnableExamples: discard
+      result = a
+    var a = 10
+    let x3 = byLent3(a) # works
+    let x2 = byLent2(a) # WAS: Error: internal error: genAddr: nkStmtListExpr
+
+  block:
+    type MyOption[T] = object
+      case has: bool
+      of true:
+        value: T
+      of false:
+        discard
+    func some[T](val: T): MyOption[T] =
+      result = MyOption[T](has: true, value: val)
+    func get[T](opt: MyOption[T]): lent T =
+      doAssert opt.has
+      # result = opt.value # this was ok
+      opt.value # this had the bug
+    let x = some(10)
+    doAssert x.get() == 10
+
 template test14339() = # bug #14339
   block:
     type
@@ -150,5 +196,10 @@ template test14339() = # bug #14339
       when not defined(js): # pending bug #16003
         doAssert a.val == 5
 
-test14339()
-static: test14339()
+template main =
+  # xxx wrap all other tests here like that so they're also tested in VM
+  test14420()
+  test14339()
+
+static: main()
+main()