1 files changed, 1 insertions, 1 deletions
diff --git a/object.c b/object.c
index 81b9b12a7a..172eacbdae 100644
--- a/object.c
+++ b/object.c
@@ -3425,7 +3425,7 @@ rb_str_to_dbl(VALUE str, int badcheck)
     (FIXNUM_P(x) ? fix2dbl_without_to_f(x) : big2dbl_without_to_f(x))
 #define num2dbl_without_to_f(x) \
     (FIXNUM_P(x) ? fix2dbl_without_to_f(x) : \
-     RB_TYPE_P(x, T_BIGNUM) ? big2dbl_without_to_f(x) : \
+     RB_BIGNUM_TYPE_P(x) ? big2dbl_without_to_f(x) : \
      (Check_Type(x, T_FLOAT), RFLOAT_VALUE(x)))
 static inline double
 rat2dbl_without_to_f(VALUE x)