Fix indirect counter increment

`*pcnt++` just dereferences `pcnt` then increments the local variable,
but has no side effect.

1 files changed, 1 insertions, 1 deletions

diff --git a/ractor.c b/ractor.c
index c18219e683..8c367e17cb 100644
--- a/ractor.c
+++ b/ractor.c
@@ -3127,7 +3127,7 @@ obj_refer_only_shareables_p_i(VALUE obj, void *ptr)
     int *pcnt = (int *)ptr;
 
     if (!rb_ractor_shareable_p(obj)) {
-        *pcnt++;
+        ++*pcnt;
     }
 }