diff --git a/gc.c b/gc.c
index 279841fd7f..ef3e1538a0 100644
--- a/gc.c
+++ b/gc.c
@@ -717,7 +717,6 @@ enum {
     BITS_SIZE = sizeof(bits_t),
     BITS_BITLENGTH = ( BITS_SIZE * CHAR_BIT )
 };
-#define popcount_bits rb_popcount_intptr
 
 struct heap_page_header {
     struct heap_page *page;