rb_thread_alloc   504 thread.c           VALUE thread = rb_thread_alloc(klass);
rb_thread_alloc   527 thread.c           return thread_create_core(rb_thread_alloc(klass), args, 0);
rb_thread_alloc   559 thread.c           return thread_create_core(rb_thread_alloc(rb_cThread), (VALUE)arg, fn);
rb_thread_alloc   568 vm_core.h      VALUE rb_thread_alloc(VALUE klass);