--- Lib/distutils/command/install_lib.py.orig	2018-04-29 22:47:33 UTC
+++ Lib/distutils/command/install_lib.py
@@ -168,10 +168,14 @@ class install_lib(Command):
             ext = os.path.splitext(os.path.normcase(py_file))[1]
             if ext != PYTHON_SOURCE_EXTENSION:
                 continue
-            if self.compile:
-                bytecode_files.append(py_file + "c")
-            if self.optimize > 0:
-                bytecode_files.append(py_file + "o")
+
+            pyc_file = py_file + "c"
+            if self.compile and os.path.isfile(pyc_file):
+                bytecode_files.append(pyc_file)
+
+            pyo_file = py_file + "o"
+            if self.optimize > 0 and os.path.isfile(pyo_file):
+                bytecode_files.append(pyo_file)
 
         return bytecode_files