diff --git a/lib/spack/spack/operating_system/cnl.py b/lib/spack/spack/operating_system/cnl.py
index e52052dfa8..07221630f2 100644
--- a/lib/spack/spack/operating_system/cnl.py
+++ b/lib/spack/spack/operating_system/cnl.py
@@ -1,7 +1,7 @@
 import spack
 from spack.architecture import OperatingSystem
 
-class ComputeNodeLinux(OperatingSystem):
+class Cnl(OperatingSystem):
     """ Compute Node Linux (CNL) is the operating system used for the Cray XC
     series super computers. It is a very stripped down version of GNU/Linux.
     Any compilers found through this operating system will be used with
@@ -11,7 +11,7 @@ class ComputeNodeLinux(OperatingSystem):
     def __init__(self):
         name = 'CNL'
         version = '10'
-        super(ComputeNodeLinux, self).__init__(name, version, "MODULES")
+        super(Cnl, self).__init__(name, version, "MODULES")
 
     def compiler_strategy(self):
         return self.compiler_strategy
diff --git a/lib/spack/spack/operating_system/linux_distro.py b/lib/spack/spack/operating_system/linux_distro.py
index b11c7a88fa..1345b7d618 100644
--- a/lib/spack/spack/operating_system/linux_distro.py
+++ b/lib/spack/spack/operating_system/linux_distro.py
@@ -1,6 +1,6 @@
 import platform as py_platform
 import spack
-from spack.architecture import Platform, OperatingSystem
+from spack.architecture import OperatingSystem
 
 class LinuxDistro(OperatingSystem):
     """ This class will represent the autodetected operating system
@@ -10,13 +10,9 @@ class LinuxDistro(OperatingSystem):
         platform.dist()
     """
     def __init__(self):
-        def detect_operating_system():
-            name = py_platform.dist()[0]
-            version = py_platform.dist()[1]
-            return name, version
+        name = py_platform.dist()[0]
+        version = py_platform.dist()[1] 
 
-        name, version = detect_operating_system()
-            
         super(LinuxDistro, self).__init__(name, version, "PATH")
     
     def compiler_strategy(self):
diff --git a/lib/spack/spack/operating_system/mac_osx.py b/lib/spack/spack/operating_system/mac_osx.py
index f52cdd6bc7..6fb6fef138 100644
--- a/lib/spack/spack/operating_system/mac_osx.py
+++ b/lib/spack/spack/operating_system/mac_osx.py
@@ -3,38 +3,30 @@
     will be represented using the major version operating system name, i.e
     el capitan, yosemite...etc.
 """
-
-import spack
-import os
 import platform as py_platform
-from spack.architecture import Platform, OperatingSystem
+import spack
+from spack.architecture import OperatingSystem
 
-class MacOSX(OperatingSystem):
+class MacOsx(OperatingSystem):
     def __init__(self):
         """ Autodetects the mac version from a dictionary. Goes back as
             far as 10.6 snowleopard. If the user has an older mac then
             the version will just be a generic mac_os.
         """
-        
-        def get_mac_release():
-            mac_releases = {'10.6': "snowleopard", 
-                            "10.7": "lion",
-                            "10.8": "mountainlion",
-                            "10.9": "mavericks",
-                            "10.10": "yosemite",
-                            "10.11": "elcapitan"}     
+        mac_releases = {'10.6': "snowleopard", 
+                        "10.7": "lion",
+                        "10.8": "mountainlion",
+                        "10.9": "mavericks",
+                        "10.10": "yosemite",
+                        "10.11": "elcapitan"}     
 
-            mac_ver = py_platform.mac_ver()[0][:-2]
-            try:
-                name = mac_releases[mac_ver]
-                return name, mac_ver
-            except KeyError:
-                name = "mac_os"
-                return name, mac_ver
+        mac_ver = py_platform.mac_ver()[0][:-2]
+        try:
+            name = mac_releases[mac_ver]
+        except KeyError:
+            name = "mac_os"
 
-        name, version = get_mac_release()
-
-        super(MacOSX, self).__init__(name, version, "PATH")
+        super(MacOsx, self).__init__(name, mac_ver, "PATH")
 
     def compiler_strategy(self):
         return self.compiler_strategy