diff --git a/src/xkbcomp/keymap.c b/src/xkbcomp/keymap.c
index eba36bd..d3c99ce 100644
--- a/src/xkbcomp/keymap.c
+++ b/src/xkbcomp/keymap.c
@@ -45,7 +45,7 @@ CompileKeymap(XkbFile *file, unsigned merge)
     Bool ok;
     unsigned required, legal;
     unsigned mainType;
-    char *mainName;
+    const char *mainName;
     LEDInfo *unbound = NULL;
     struct xkb_desc *xkb = XkbcAllocKeyboard();
     struct {