diff --git a/edalize/vivado.py b/edalize/vivado.py
index 4221a8a6..45edd61f 100644
--- a/edalize/vivado.py
+++ b/edalize/vivado.py
@@ -111,8 +111,14 @@ def build_main(self):
         if "pnr" in self.tool_options:
             if self.tool_options["pnr"] == "vivado":
                 pass
-            elif self.tool_options["pnr"] == "none":
+            elif (
+                self.tool_options["pnr"] == "none"
+                and self.tool_options["synth"] != "none"
+            ):
                 args.append("synth")
+            else:
+                args.append("post_build")
+
         self._run_tool("make", args)
 
     def run_main(self):