thread.c: during GC for thread

* thread.c (ruby_thread_stack_overflow): check if the given thread
  is during GC.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58328 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

gc.c

@@ -6651,6 +6651,13 @@ rb_during_gc(void)
     return during_gc;
 }
 
+int
+rb_threadptr_during_gc(rb_thread_t *th)
+{
+    rb_objspace_t *objspace = rb_objspace_of(th->vm);
+    return during_gc;
+}
+
 #if RGENGC_PROFILE >= 2
 
 static const char *type_name(int type, VALUE obj);

gc.h

@@ -90,6 +90,9 @@ const char *rb_obj_info(VALUE obj);
 const char *rb_raw_obj_info(char *buff, const int buff_size, VALUE obj);
 void rb_obj_info_dump(VALUE obj);
 
+struct rb_thread_struct;
+int rb_threadptr_during_gc(struct rb_thread_struct *th);
+
 RUBY_SYMBOL_EXPORT_BEGIN
 
 /* exports for objspace module */

thread.c

@@ -2171,7 +2171,7 @@ ruby_thread_stack_overflow(rb_thread_t *th)
 {
     th->raised_flag = 0;
 #ifdef USE_SIGALTSTACK
-    if (!rb_during_gc()) {
+    if (!rb_threadptr_during_gc(th)) {
 	rb_exc_raise(sysstack_error);
     }
 #endif