diff --git a/SConstruct b/SConstruct
index 8c79191c92e..02d5ad42cd6 100755
--- a/SConstruct
+++ b/SConstruct
@@ -326,27 +326,34 @@ if env["prereqs"]:
         conf.CheckLib("mikmod")
 
     if env['sdl2']:
-        have_sdl_net = \
-        conf.CheckSDL(require_version = '2.0.0') & \
-        conf.CheckSDL("SDL2_net", header_file = "SDL_net")
+        def have_sdl_net():
+            return \
+                conf.CheckSDL(require_version = '2.0.0') & \
+                conf.CheckSDL("SDL2_net", header_file = "SDL_net")
 
-        have_sdl_other = \
-        conf.CheckSDL("SDL2_ttf", header_file = "SDL_ttf") & \
-        conf.CheckSDL("SDL2_mixer", header_file = "SDL_mixer") & \
-        conf.CheckSDL("SDL2_image", header_file = "SDL_image")
+        def have_sdl_other():
+            return \
+                conf.CheckSDL(require_version = '2.0.0') & \
+                conf.CheckSDL("SDL2_ttf", header_file = "SDL_ttf") & \
+                conf.CheckSDL("SDL2_mixer", header_file = "SDL_mixer") & \
+                conf.CheckSDL("SDL2_image", header_file = "SDL_image")
 
     else:
-        have_sdl_net = \
-        conf.CheckSDL(require_version = '1.2.0') & \
-        conf.CheckSDL('SDL_net')
+        def have_sdl_net():
+            return \
+                conf.CheckSDL(require_version = '1.2.0') & \
+                conf.CheckSDL('SDL_net')
 
-        have_sdl_other = \
-        conf.CheckSDL("SDL_ttf", require_version = "2.0.8") & \
-        conf.CheckSDL("SDL_mixer", require_version = '1.2.0') & \
-        conf.CheckSDL("SDL_image", require_version = '1.2.0')
+        def have_sdl_other():
+            return \
+                conf.CheckSDL(require_version = '1.2.0') & \
+                conf.CheckSDL("SDL_ttf", require_version = "2.0.8") & \
+                conf.CheckSDL("SDL_mixer", require_version = '1.2.0') & \
+                conf.CheckSDL("SDL_image", require_version = '1.2.0')
 
-    have_server_prereqs = have_sdl_net & \
+    have_server_prereqs = \
         conf.CheckCPlusPlus(gcc_version = "3.3") & \
+        have_sdl_net() & \
         conf.CheckGettextLibintl() & \
         conf.CheckBoost("iostreams", require_version = "1.34.1") & \
         conf.CheckBoostIostreamsGZip() & \
@@ -357,7 +364,7 @@ if env["prereqs"]:
     env = conf.Finish()
     client_env = env.Clone()
     conf = client_env.Configure(**configure_args)
-    have_client_prereqs = have_server_prereqs & have_sdl_other & \
+    have_client_prereqs = have_server_prereqs & have_sdl_other() & \
         CheckAsio(conf) & \
         conf.CheckPango("cairo", require_version = "1.21.3") & \
         conf.CheckPKG("fontconfig") & \