diff --git a/scripts/genconfig.py b/scripts/genconfig.py
index d9513ddc0..d8e1f7e89 100755
--- a/scripts/genconfig.py
+++ b/scripts/genconfig.py
@@ -6,6 +6,14 @@ import sys
 comment = re.compile('^\s*#')
 assign = re.compile('^\s*([a-zA-Z_]+)\s*(\?)?=\s*([^#]*)')
 
+args = {}
+for arg in sys.argv:
+    m = assign.match(arg)
+    if m:
+        var = m.group(1).strip()
+        val = m.group(3).strip()
+        args[var] = val
+
 with open('CONFIG') as f:
     for line in f:
         line = line.strip()
@@ -15,13 +23,8 @@ with open('CONFIG') as f:
                 var = m.group(1).strip()
                 default = m.group(3).strip()
                 val = default
-                for arg in sys.argv:
-                    m = assign.match(arg)
-                    if m:
-                        argvar = m.group(1).strip()
-                        argval = m.group(3).strip()
-                        if argvar == var:
-                            val = argval
+                if var in args:
+                    val = args[var]
                 if default.lower() == 'y' or default.lower() == 'n':
                     if val.lower() == 'y':
                         print "#define SPDK_{} 1".format(var)