Never increment `max_iv_count` on Object / BasicObject.

Otherwise some code defining ivars on a naked object early during
program boot can cause all objects to be larger than needed.

This seem like it was always the intention, but wasn't quite
properly prevented.

Also stop updating `max_iv_count` during GC marking as it is
redundant.

1 files changed, 1 insertions, 0 deletions

diff --git a/object.c b/object.c
index eaec5e89d2..23a83c572e 100644
--- a/object.c
+++ b/object.c
@@ -2224,6 +2224,7 @@ rb_class_initialize(int argc, VALUE *argv, VALUE klass)
         }
     }
     rb_class_set_super(klass, super);
+    RCLASS_SET_MAX_IV_COUNT(klass, RCLASS_MAX_IV_COUNT(super));
     RCLASS_SET_ALLOCATOR(klass, RCLASS_ALLOCATOR(super));
     rb_make_metaclass(klass, RBASIC(super)->klass);
     rb_class_inherited(super, klass);