diff --git a/ZeekPluginStatic.cmake b/ZeekPluginStatic.cmake
index 44db57b..73fc9ac 100644
--- a/ZeekPluginStatic.cmake
+++ b/ZeekPluginStatic.cmake
@@ -52,10 +52,12 @@ function (zeek_add_static_plugin ns name)
         zeek_next_pac_block(at_end pacInputs pacRemainder ${pacRemainder})
     endwhile ()
 
-    if (MSVC)
-        #set(WERROR_FLAG "/WX")
-    else ()
-        set(WERROR_FLAG "-Werror")
+    if (BUILD_WITH_WERROR)
+        if (MSVC)
+            #set(WERROR_FLAG "/WX")
+        else ()
+            set(WERROR_FLAG "-Werror")
+        endif ()
     endif ()
 
     # Pass compiler flags, paths and dependencies to the target.