extern int prefer_symlink_refs;
extern int warn_ambiguous_refs;
extern int warn_on_object_refname_ambiguity;
-extern const char *apply_default_whitespace;
-extern const char *apply_default_ignorewhitespace;
+extern char *apply_default_whitespace;
+extern char *apply_default_ignorewhitespace;
extern const char *git_attributes_file;
extern const char *git_hooks_path;
extern int zlib_compression_level;