Never shrink bignum on realloc

As far as I can tell, this only ever shrinks by one, and it's really not
worth the expensive realloc for that.

1 files changed, 1 insertions, 1 deletions

diff --git a/bignum.c b/bignum.c
index 9e8d6a91f1..8d3eac8e0a 100644
--- a/bignum.c
+++ b/bignum.c
@@ -3048,7 +3048,7 @@ rb_big_realloc(VALUE big, size_t len)
             if (BIGNUM_LEN(big) == 0) {
                 RBIGNUM(big)->as.heap.digits = ALLOC_N(BDIGIT, len);
             }
-            else {
+            else if (BIGNUM_LEN(big) < len) {
                 REALLOC_N(RBIGNUM(big)->as.heap.digits, BDIGIT, len);
             }
         }