mark_stack_size   870 gc.c           static size_t mark_stack_size(mark_stack_t *stack);
mark_stack_size  5281 gc.c               gc_report(1, objspace, "gc_marks_start: (%s) end, stack in %d\n", full_mark ? "full" : "minor", (int)mark_stack_size(&objspace->mark_stack));
mark_stack_size  5352 gc.c           	    rb_bug("gc_marks_finish: mark stack is not empty (%d).", (int)mark_stack_size(&objspace->mark_stack));
mark_stack_size  5358 gc.c           	    gc_report(1, objspace, "gc_marks_finish: not empty (%d). retry.\n", (int)mark_stack_size(&objspace->mark_stack));
mark_stack_size  5541 gc.c           	    gc_report(2, objspace, "gc_marks_continue: no more pooled pages (stack depth: %d).\n", (int)mark_stack_size(&objspace->mark_stack));