Make imemo_alloc writebarrier-unprotected

imemo_alloc provides a memory buffer whose contents are marked by GC.
C code can access imemo_alloc buffer freely, so imemo_alloc must be
considered writebarrier-unprotected.  But T_IMEMO is writebarrier-
protected by default, which caused a GC bug.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60427 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/gc.c b/gc.c
index 086b6ad96e..6e32997b8e 100644
--- a/gc.c
+++ b/gc.c
@@ -8118,6 +8118,7 @@ rb_alloc_tmp_buffer_with_count(volatile VALUE *store, size_t size, size_t cnt)
     void *ptr;
 
     s = rb_imemo_new(imemo_alloc, 0, 0, 0, 0);
+    rb_gc_writebarrier_unprotect(s);
     ptr = ruby_xmalloc0(size);
     a = (rb_imemo_alloc_t*)s;
     a->ptr = (VALUE*)ptr;