diff --git a/util.h b/util.h
index 458a553..9d2c5dd 100644
--- a/util.h
+++ b/util.h
@@ -57,5 +57,6 @@ char *humansize(double);
 mode_t parsemode(const char *, mode_t, mode_t);
 void putword(const char *);
 void recurse(const char *, void (*)(const char *));
+#undef strtonum
 long long strtonum(const char *, long long, long long, const char **);
 size_t unescape(char *);