diff --git a/src/tinf.h b/src/tinf.h
index d82959d..e9401f2 100644
--- a/src/tinf.h
+++ b/src/tinf.h
@@ -76,7 +76,7 @@ int TINFCC tinf_zlib_uncompress_dyn(TINF_DATA *d, unsigned int sourceLen);
 
 /* high-level API */
 
-void TINFCC tinf_init();
+void TINFCC tinf_init(void);
 
 int TINFCC tinf_uncompress(void *dest, unsigned int *destLen,
                            const void *source, unsigned int sourceLen);
diff --git a/src/tinflate.c b/src/tinflate.c
index d5197a5..6deeda2 100644
--- a/src/tinflate.c
+++ b/src/tinflate.c
@@ -432,7 +432,7 @@ static int tinf_inflate_dynamic_block(TINF_DATA *d)
  * ---------------------- */
 
 /* initialize global (static) data */
-void tinf_init()
+void tinf_init(void)
 {
 #ifdef RUNTIME_BITS_TABLES
    /* build extra bits and base tables */