diff --git a/ext/standard/crc32.c b/ext/standard/crc32.c
index 374fee381593a..602ce3eeb6e2b 100644
--- a/ext/standard/crc32.c
+++ b/ext/standard/crc32.c
@@ -39,7 +39,7 @@ static unsigned long getauxval(unsigned long key) {
 }
 # endif
 
-static inline int has_crc32_insn() {
+static inline int has_crc32_insn(void) {
 	/* Only go through the runtime detection once. */
 	static int res = -1;
 	if (res != -1)