diff --git a/c/common/dictionary.c b/c/common/dictionary.c
index 3075257..7c015ab 100644
--- a/c/common/dictionary.c
+++ b/c/common/dictionary.c
@@ -5897,7 +5897,7 @@
 #endif
 };
 
-const BrotliDictionary* BrotliGetDictionary() {
+const BrotliDictionary* BrotliGetDictionary(void) {
   return &kBrotliDictionary;
 }
 
diff --git a/c/dec/decode.c b/c/dec/decode.c
index 2fe58a7..41166f9 100644
--- a/c/dec/decode.c
+++ b/c/dec/decode.c
@@ -2776,7 +2776,7 @@
   }
 }
 
-uint32_t BrotliDecoderVersion() {
+uint32_t BrotliDecoderVersion(void) {
   return BROTLI_VERSION;
 }