variable.c: fix implicit conversion

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@54701 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 4 insertions, 3 deletions

diff --git a/variable.c b/variable.c
index c729a08803..9c3ce2d182 100644
--- a/variable.c
+++ b/variable.c
@@ -1079,11 +1079,12 @@ gen_ivtbl_dup(const struct gen_ivtbl *orig)
 static uint32_t
 iv_index_tbl_newsize(struct ivar_update *ivup)
 {
-    uint32_t newsize = (ivup->index+1) + (ivup->index+1)/4; /* (index+1)*1.25 */
+    uint32_t index = (uint32_t)ivup->index;	/* should not overflow */
+    uint32_t newsize = (index+1) + (index+1)/4; /* (index+1)*1.25 */
 
     if (!ivup->iv_extended &&
         ivup->u.iv_index_tbl->num_entries < (st_index_t)newsize) {
-        newsize = ivup->u.iv_index_tbl->num_entries;
+        newsize = (uint32_t)ivup->u.iv_index_tbl->num_entries;
     }
     return newsize;
 }
@@ -1381,7 +1382,7 @@ rb_ivar_set(VALUE obj, ID id, VALUE val)
             }
             else {
                 VALUE *newptr;
-                long newsize = iv_index_tbl_newsize(&ivup);
+                uint32_t newsize = iv_index_tbl_newsize(&ivup);
 
                 if (RBASIC(obj)->flags & ROBJECT_EMBED) {
                     newptr = ALLOC_N(VALUE, newsize);