fixes #5079

tests/ccgbugs/tmissingderef2.nim

@@ -0,0 +1,25 @@
+discard """
+  output: "c"
+"""
+
+# bug #5079
+
+import tables, strutils
+
+type Test = ref object
+  s: string
+
+proc `test=`(t: Test, s: string) =
+  t.s = s
+
+var t = Test()
+
+#t.test = spaces(2) # -- works
+
+var a = newTable[string, string]()
+a["b"] = "c"
+
+#t.s = a["b"] # -- works
+#t.test a["b"] # -- works
+t.test = a["b"] # -- prints "out of memory" and quits
+echo t.s