diff --git a/setup.py b/setup.py
index f47cdd192..cc75244ab 100644
--- a/setup.py
+++ b/setup.py
@@ -421,9 +421,6 @@ def create_cryptodome_lib():
         ),
 ]
 
-# Add compiler specific options.
-set_compiler_options(package_root, ext_modules)
-
 if use_separate_namespace:
 
     # Fix-up setup information
@@ -442,6 +439,8 @@ def create_cryptodome_lib():
     if os.path.isdir("lib/Crypto"):
         create_cryptodome_lib()
 
+# Add compiler specific options.
+set_compiler_options(package_root, ext_modules)
 
 # By doing this we need to change version information in a single file
 with open(os.path.join("lib", package_root, "__init__.py")) as init_root: