--- a/setup.py
+++ b/setup.py
@@ -454,13 +454,8 @@ class PyBuildExt(build_ext):
             os.unlink(tmpfile)
 
     def detect_modules(self):
-        # Ensure that /usr/local is always used
-        if not cross_compiling:
-            add_dir_to_list(self.compiler.library_dirs, '/usr/local/lib')
-            add_dir_to_list(self.compiler.include_dirs, '/usr/local/include')
         if cross_compiling:
             self.add_gcc_paths()
-        self.add_multiarch_paths()
 
         # Add paths specified in the environment variables LDFLAGS and
         # CPPFLAGS for header and library files.
