--- kpathsea.c
+++ kpathsea.c
@@ -36,7 +36,7 @@
 
 void version_findtfm(void)
 {
-        extern char * kpathsea_version_string;
+        extern const char * kpathsea_version_string;
         puts(kpathsea_version_string);
 }