add -Wmissing-declarations to -Wall

diff --git a/warning.c b/warning.c
index d8931d7..6804537 100644 (file)
--- a/warning.c
+++ b/warning.c
@@ -169,6 +169,7 @@ void set_warning_opt(const char *const opt)
                SET(implicit_int);
                SET(init_self);
                SET(main);
+               SET(missing_declarations);
                SET(nonnull);
                SET(parentheses);
                SET(pointer_arith);