diff --git a/dist/tools/kconfiglib/genconfig.py b/dist/tools/kconfiglib/genconfig.py
index 3269b6903a53..093d78507a34 100755
--- a/dist/tools/kconfiglib/genconfig.py
+++ b/dist/tools/kconfiglib/genconfig.py
@@ -33,6 +33,7 @@
 import os
 import sys
 
+from riot_kconfig import RiotKconfig
 import kconfiglib
 
 
@@ -386,7 +387,7 @@ def main():
     logging.basicConfig(format='[genconfig.py]:%(levelname)s-%(message)s',
                         level=log_level)
 
-    kconf = kconfiglib.Kconfig(args.kconfig_filename, warn_to_stderr=False)
+    kconf = RiotKconfig(args.kconfig_filename, warn_to_stderr=False)
     merge_configs(kconf, args.config_sources)
 
     # HACK: Force all symbols to be evaluated, to catch warnings generated
diff --git a/dist/tools/kconfiglib/riot_kconfig.py b/dist/tools/kconfiglib/riot_kconfig.py
index 01bb796e30d0..bf51e0a78eb9 100644
--- a/dist/tools/kconfiglib/riot_kconfig.py
+++ b/dist/tools/kconfiglib/riot_kconfig.py
@@ -18,6 +18,16 @@ def _parse_help(self, node):
         for marker in doxygen_markers:
             node.help = node.help.replace(marker, "")
 
+    def write_autoconf(self, filename=None, header=None):
+        """ Override to convert - to _ when writing autoconf.h """
+        tmp_unique_defined_syms = self.unique_defined_syms.copy()
+        for sym in self.unique_defined_syms:
+            if not sym._write_to_conf:
+                continue
+            sym.name = sym.name.replace('-', '_')
+        super(RiotKconfig, self).write_autoconf(filename, header)
+        self.unique_defined_syms = tmp_unique_defined_syms
+
 
 def standard_riot_kconfig(description=None):
     """