fix #5017; fix #5893

compiler/sigmatch.nim

@@ -204,7 +204,9 @@ proc sumGeneric(t: PType): int =
         if t.sons[i] != nil:
           result += t.sons[i].sumGeneric
       break
-    of tyGenericParam, tyExpr, tyStatic, tyStmt: break
+    of tyStatic:
+      return t.sons[0].sumGeneric + 1
+    of tyGenericParam, tyExpr, tyStmt: break
     of tyAlias: t = t.lastSon
     of tyBool, tyChar, tyEnum, tyObject, tyPointer,
         tyString, tyCString, tyInt..tyInt64, tyFloat..tyFloat128,

tests/overload/tstaticoverload.nim

@@ -0,0 +1,26 @@
+discard """
+output: '''
+dynamic: let
+dynamic: var
+static: const
+static: literal
+static: constant folding
+'''
+"""
+
+proc foo(s: string) =
+  echo "dynamic: ", s
+
+proc foo(s: static[string]) =
+  echo "static: ", s
+
+let l = "let"
+let v = "var"
+const c = "const"
+
+foo(l)
+foo(v)
+foo(c)
+foo("literal")
+foo("constant" & " " & "folding")
+